CN105004551A - Method for progressively recognizing load of damaged cable based on space coordinate monitoring process of streamlined annular displacement - Google Patents

Abstract

Simplified angular displacement spatial coordinate monitoring The progressive identification method of damaged cable load is based on spatial coordinate monitoring, and determines whether the cable structure needs to be updated by monitoring the angular displacement of the support, the temperature of the cable structure, the ambient temperature, the degree of load change and the degree of damage of the damaged cable Based on the benchmark model of mechanical calculation, a new benchmark model of mechanical calculation of the cable structure that takes into account the angular displacement of the support, the degree of load change, the degree of damage of the damaged cable, and the temperature is obtained. Based on this model, the current numerical vector of the monitored quantity The approximate linear relationship exists between the current initial value vector of the monitored quantity, the numerical change matrix of the monitored quantity per unit damage, and the current nominal damage vector to be obtained, so that the health status of the core evaluated object can be identified.

Description

Simplified Angular Displacement Space Coordinates Monitoring Damaged Cable Load Progressive Identification Method

technical field

Cable-stayed bridges, suspension bridges, truss structures and other structures have one thing in common, that is, they have many parts that bear tensile loads, such as cable-stayed cables, main cables, slings, tie rods, etc. , cables, or rods that only bear tensile loads are supporting components. For the sake of convenience, this method expresses this type of structure as For the sake of convenience, the rods with tensile or axial compression loads (also known as two-force rods) are collectively referred to as "cable systems". In this method, the term "supporting cables" is used to refer to load-bearing cables, A member that bears axial tension or axial compression load is sometimes referred to as a "cable", so when the word "cable" is used later, it actually refers to a two-force member for a truss structure. During the service process of the structure, the correct identification of the health state of the supporting cables or the cable system is related to the safety of the entire cable structure. When the ambient temperature changes, the temperature of the cable structure will generally change accordingly. When the temperature of the cable structure changes, the angular displacement of the support of the cable structure may occur, and the load on the cable structure may also change. The state of health may also be changing. Under such complex conditions, this method is based on spatial coordinate monitoring (this method refers to the monitored spatial coordinates as "monitored quantities") to identify damaged cables (this method is called core The health status of the assessed object) belongs to the field of engineering structure health monitoring.

Background technique

It is an urgent problem to be solved at present to eliminate the influence of load change, angular displacement of cable structure support and structure temperature change on the identification results of the health state of the cable structure, so as to accurately identify the change of the health state of the structure. an effective and inexpensive method.

Contents of the invention

Technical problem: This method discloses a method, under the condition of lower construction cost, when the support has angular displacement, when the load on the structure and the structure (environment) temperature change, the angular displacement of the support and the change of the load can be eliminated And the impact of structural temperature changes on the identification results of the cable structure health status, so as to accurately identify the health status of the supporting cables.

Technical solution: In this method, "support space coordinates" refers to the coordinates of the support on the X, Y, and Z axes of the Cartesian coordinate system, and can also be said to be the space of the support on the X, Y, and Z axes. Coordinates, the specific value of the spatial coordinate of the support about a certain axis is called the spatial coordinate component of the support about the axis. In this method, a spatial coordinate component of the support is also used to express the specific value of the spatial coordinate of the support about a certain axis. Numerical value; use "support angular coordinates" to refer to the angular coordinates of the support with respect to the X, Y, and Z axes, and the specific value of the angular coordinates of the support with respect to a certain axis is called the angular coordinate component of the support with respect to the axis. In this method An angular coordinate component of the support is also used to express the specific value of the angular coordinate of the support with respect to a certain axis; the "generalized coordinate of the support" is used to refer to the angular coordinates of the support and the space coordinates of the support as a whole. In this method, the support's A generalized coordinate component expresses the specific value of the space coordinate or angular coordinate of the support about an axis; the change of the coordinate of the support about the X, Y, and Z axes is called the line displacement of the support, and it can also be said that the change of the space coordinate of the support is called is the linear displacement of the support. In this method, a linear displacement component of the support is also used to express the specific value of the linear displacement of the support about a certain axis; the change of the angular coordinates of the support about the X, Y, and Z axes is called the support Angular displacement, in this method, an angular displacement component of the support is also used to express the specific value of the angular displacement of the support with respect to a certain axis; the generalized displacement of the support refers to the overall displacement of the support line and the angular displacement of the support, and this method also uses A generalized displacement component of the support expresses the specific value of the linear displacement or angular displacement of the support about a certain axis; the linear displacement of the support can also be called translational displacement, and the settlement of the support is the linear displacement or translational displacement of the support in the direction of gravity portion.

The external force borne by objects and structures can be called load, and the load includes surface load and body load. Surface load, also known as surface load, is a load acting on the surface of an object, including concentrated load and distributed load. Body load is the load continuously distributed at various points inside the object, such as the object's own weight and inertial force.

Concentrated load is divided into concentrated force and concentrated force couple. In a coordinate system, such as a Cartesian rectangular coordinate system, a concentrated force can be decomposed into three components. Similarly, a concentrated force couple can also be decomposed into three components. If the load is actually a concentrated load, a concentrated force component or a concentrated force couple component is called a load in this method, and the change of the load at this time is embodied as a change of a concentrated force component or a concentrated force couple component.

Distributed load is divided into line distributed load and surface distributed load. The description of distributed load includes at least the action area of distributed load and the size of distributed load. , sine function and other distribution characteristics) and amplitude to express (for example, two distributed loads are uniformly distributed, but their amplitudes are different, uniform pressure can be used as an example to illustrate the concept of amplitude: the same structure bears two different loads Uniformly distributed pressure, both distributed loads are uniformly distributed loads, but the amplitude of one distributed load is 10MPa, and the amplitude of the other distributed load is 50MPa). If the load is actually a distributed load, when this method talks about the change of the load, it actually refers to the change of the amplitude of the distribution concentration of the distributed load, while the action area of the distributed load and the distribution characteristics of the distribution concentration remain unchanged. In the coordinate system, a distributed load can be decomposed into several components. If the amplitudes of the respective distribution concentration of several components of the distributed load change, and the ratios of the changes are not all the same, then in this method, the Several distributed load components are regarded as the same number of independent distributed loads. At this time, one load represents a distributed load component, and the components with the same amplitude change ratio of the distribution concentration can also be combined into a distributed load or called for a load.

Body load is the load continuously distributed at various points inside the object, such as the self-weight and inertial force of the object. The description of the body load includes at least the action area of the body load and the size of the body load. The size of the body load is expressed by the distribution concentration, and the distribution Concentration is expressed by distribution characteristics (such as uniform distribution, linear function and other distribution characteristics) and amplitude (for example, two body loads are uniformly distributed, but their amplitudes are different. The concept of amplitude can be illustrated by self-weight as an example: the same The two parts of a structure are made of different materials and therefore have different densities, so although the body loads on both parts are uniformly distributed, the magnitude of the body load on one part may be 10kN/m ³ and the other may be A part is subjected to a body load of magnitude 50kN/m ³ ). If the load is actually a body load, what is actually dealt with in this method is the change in the magnitude of the distribution concentration of the body load, while the action area of the body load and the distribution characteristics of the distribution concentration remain unchanged. At this time, in this method When referring to the change of the load in , it actually refers to the change of the magnitude of the distribution concentration of the body load. At this time, the changed load refers to the body load whose distribution concentration changes. In the coordinate system, a body load can be decomposed into several components (for example, in the Cartesian coordinate system, the body load can be decomposed into components about the three axes of the coordinate system, that is, in the Cartesian coordinate system The body load can be decomposed into three components), if the magnitude of the respective distribution concentration of several components of the body load changes, and the change ratios are not all the same, then in this method, the The components are regarded as the same number of independent loads, and the body load components with the same amplitude change ratio of the distribution concentration can also be synthesized into a body load or called a load.

When the load is embodied as concentrated load, in this method, "load unit change" actually refers to "unit change of concentrated load", similarly, "load change" specifically refers to "change in magnitude of concentrated load", " "Load change" specifically refers to "the change in the size of the concentrated load", "the degree of load change" specifically refers to the "change degree of the concentrated load", and "the actual change in the load" refers to the "actual change in the size of the concentrated load". Amount", "changed load" refers to "concentrated load whose size changes". Simply put, at this time, "a certain change in a certain load" refers to "a certain change in the size of a certain concentrated load".

When the load is embodied as a distributed load, in this method, "the unit change of the load" actually refers to "the unit change of the amplitude of the distribution concentration of the distributed load", and the distribution characteristics of the distributed load are unchanged, similar to The "load change" specifically refers to "the change in the magnitude of the distribution concentration of the distributed load", while the distribution characteristics of the distributed load are unchanged, and the "load change" specifically refers to the "magnitude of the distribution concentration of the distributed load". The change amount of the load", "the degree of load change" specifically refers to the "change degree of the amplitude of the distribution concentration of the distributed load", and the "actual change of the load" specifically refers to the "actual change of the amplitude of the distribution concentration of the distributed load ", "changed load" refers to "distributed load whose amplitude of distribution intensity changes". A certain change in the amplitude of the load", while the distribution characteristics of the action area and distribution concentration of all distributed loads remain unchanged.

When the load is embodied as body load, in this method, "load unit change" actually refers to "unit change in the amplitude of distribution concentration of body load", similarly, "load change" means "body load The change of the magnitude of the distribution concentration of the body load", the "load change" refers to the "change of the magnitude of the distribution concentration of the body load", and the "load change degree" refers to the "magnitude of the distribution concentration of the body load The degree of change", "the actual change of the load" refers to the "actual change of the magnitude of the distribution concentration of the body load", and "the changed load" refers to the "body load whose distribution concentration changes. ", simply put, "a certain change in a certain load" refers to "a certain change in the magnitude of the distribution concentration of a certain body load", and the distribution characteristics of the action area and distribution concentration of all body loads are Changeless.

This method specifically includes:

a. When the load borne by the cable structure changes, but the load the cable structure is bearing does not exceed the initial allowable load of the cable structure, this method is applicable; the initial allowable load of the cable structure refers to the allowable load of the cable structure at the time of completion, It can be obtained through conventional mechanical calculations; this method collectively refers to the evaluated supporting cables and loads as "assessed objects", and the sum of the number of evaluated supporting cables and the number of loads is N, which is the number of "assessed objects" is N; this method uses the name "core assessed object" to specifically refer to the assessed support cables in the "assessed object", and this method uses the name "secondary assessed object" to specifically refer to the assessed support cable in the "assessed object". load; determine the numbering rule of the evaluated object, according to this rule, number all the evaluated objects in the cable structure, and the number will be used to generate vectors and matrices in subsequent steps; this method uses the variable k to represent this number, k =1,2,3,…,N; Suppose there are M ₁ supporting cables in the cable system, obviously the number of the core evaluated objects is M ₁ ; determine the measured points of the designated space coordinates to be monitored, and give all designated points Numbering; the space coordinate components to be monitored of each measurement point have been determined, and all measured space coordinate components are numbered; the above numbers will be used to generate vectors and matrices in subsequent steps; "all the monitored space coordinates of the cable structure Data" is composed of all the above-mentioned measured spatial coordinate components; for the sake of convenience, in this method, the "monitored spatial coordinate data of the cable structure" is referred to as "monitored quantity"; the sum of all monitored quantities is recorded as M, M is greater than the number of core evaluated objects, and M is smaller than the number of evaluated objects; in this method, the time interval between any two measurements of real-time monitoring of the same quantity shall not be greater than 30 minutes, and the moment of measuring and recording data is called Actual data recording time; the external force borne by objects and structures can be called load, and load includes surface load and body load; surface load, also known as surface load, is a load acting on the surface of an object, including concentrated load and distributed load; body load It is the load continuously distributed at each point inside the object, including the self-weight and inertial force of the object; the concentrated load is divided into two types: concentrated force and concentrated force couple. In the coordinate system including the Cartesian coordinate system, a concentrated force It can be decomposed into three components. Similarly, a concentrated force couple can also be decomposed into three components. If the load is actually a concentrated load, a concentrated force component or a concentrated force couple component is counted or counted as a load in this method , the change of the load at this time is embodied as the change of a concentrated force component or a concentrated force couple component; distributed load is divided into line distributed load and surface distributed load, and the description of distributed load includes at least the action area of distributed load and the size of distributed load, The size of the distributed load is expressed by the distribution concentration, and the distribution concentration is expressed by the distribution characteristics and amplitude; if the load is actually a distributed load, when this method talks about the change of the load, it actually refers to the amplitude of the distribution concentration of the distributed load. The value changes, while the distribution characteristics of the action area and distribution intensity of all distributed loads remain unchanged; in a coordinate system including Cartesian coordinate system, a The distributed load can be decomposed into three components. If the magnitudes of the respective distribution concentration of the three components of the distributed load change, and the ratios of the changes are not all the same, then in this method, the three components of the distributed load It is counted or counted as three distributed loads. At this time, one load represents a component of the distributed load; the body load is the load continuously distributed at each point inside the object, and the description of the body load includes at least the action area of the body load and the area of the body load The size of the body load is expressed by the distribution concentration, and the distribution concentration is expressed by the distribution characteristics and amplitude; if the load is actually a body load, what is actually dealt with in this method is the magnitude of the distribution concentration of the body load change, while the distribution characteristics of the action area and distribution concentration of all body loads remain unchanged. At this time, when the load change is mentioned in this method, it actually refers to the change of the magnitude of the distribution concentration of the body load. When , the loads that change refer to those body loads whose magnitude of distribution concentration changes; in a coordinate system including Cartesian coordinate system, a body load can be decomposed into three components, if the body load If the amplitudes of the respective distribution concentration of the three components change, and the ratios of the changes are not all the same, then in this method, the three components of the body load are counted or counted as three distributed loads;

b. This method defines "the temperature measurement and calculation method of the cable structure of this method" according to steps b1 to b3;

b1: Query or measure the temperature-dependent heat transfer parameters of the composition materials of the cable structure and the environment where the cable structure is located, use the design drawings, as-built drawings of the cable structure, and the geometrically measured data of the cable structure, and use these data and parameters to establish a cable structure. The heat transfer calculation model of the structure; query the meteorological data of not less than 2 years in recent years where the cable structure is located, and count the number of cloudy days during this period as T cloudy days. In this method, the number of cloudy days that cannot be seen during the day The whole day of the sun is called a cloudy day, and the highest and lowest temperature between 0:00 and 30 minutes after the sunrise time of the next day on each of the T cloudy days is counted. The meteorological sunrise time determined by the sun and the revolution law does not mean that the sun must be visible on that day, and the required sunrise time of each day can be obtained by querying the data or through conventional meteorological calculations. Every cloudy day from 0 o'clock to The maximum temperature difference between the highest temperature and the lowest temperature within 30 minutes after sunrise of the next day is called the maximum temperature difference of the daily temperature of the cloudy day. If there are T cloudy days, there will be the maximum temperature difference of the daily temperature of T cloudy days. Take T The maximum value of the maximum temperature difference of daily air temperature in a cloudy day is the reference daily temperature difference, which is recorded as ΔT _r ; query the location of the cable structure and the altitude interval of not less than 2 years of meteorological data in recent years or obtain the cable structure from actual measurements The change data and change law of the temperature of the environment with time and altitude, and the maximum change rate ΔT of the temperature of the environment where the cable structure is located with respect to the altitude in recent years for the location of the cable structure and the altitude interval of not less than 2 years in recent years _h , for the convenience of description, the unit of ΔT _h is ℃/m; take "R cable structure surface points" on the surface of the cable structure, and the specific principle of taking "R cable structure surface points" is described in step b3, and later The temperature of the surface points of the R cable structures will be obtained through actual measurement, and the temperature data obtained from the actual measurement is called "the measured data of the surface temperature of the R cable structures". The temperature of the surface points of the R cable structures is called the calculated temperature data as "calculation data of the surface temperature of the R cable structures"; For less than three different altitudes, at each selected altitude, at least two points are selected at the intersection of the horizontal plane and the surface of the cable structure, and the outer normal of the surface of the structure is indexed from the selected point, all selected The outer normal direction is called "the direction of measuring the temperature distribution of the cable structure along the wall thickness". The direction of temperature distribution along the wall thickness must include the outer normal direction of the sunny surface of the cable structure and the outer normal direction of the shaded surface of the cable structure, and the temperature distribution along the wall thickness of each measurement cable structure is uniform in the cable structure. Select no less than three points, for the support cable along the direction of each measuring cable structure temperature distribution along the wall thickness, only take one point, only measure the temperature of the surface point of the support cable, measure the temperature of all selected points, measure The obtained temperature is called "the temperature distribution data of the cable structure along the thickness", Among them, the "temperature distribution data of the cable structure along the thickness" measured along the same "intersection line between the horizontal plane and the surface of the cable structure" and "the direction of measuring the temperature distribution of the cable structure along the wall thickness" is called in this method "The temperature distribution data of the cable structure along the thickness at the same altitude", assume that H different altitudes are selected, and at each altitude, B are selected to measure the temperature distribution direction of the cable structure along the wall thickness, along each To measure the temperature distribution direction of the cable structure along the wall thickness, E points are selected in the cable structure, where H and E are not less than 3, and B is not less than 2. For the supporting cable, E is equal to 1. On the cable structure, "measurement cable structure The total number of "points of temperature distribution data along the thickness" is HBE, and the temperature of these HBE "points of temperature distribution data along the thickness of the cable structure" will be obtained through actual measurement later, and the temperature data obtained by actual measurement are called "HBE cable The measured data of the temperature along the thickness of the structure”, if the heat transfer calculation model of the cable structure is used to calculate the temperature of the HBE points that measure the temperature distribution data of the cable structure along the thickness, the calculated temperature data is called "HBE cable structure temperature calculation data along the thickness"; select a location at the location of the cable structure according to the meteorological temperature measurement requirements, and the temperature of the environment where the cable structure is located that meets the meteorological temperature measurement requirements will be measured at this location; at the location of the cable structure Choose a location in an open and unsheltered place, which should be able to get the fullest sunshine of the day every day of the year, and place a carbon steel plate at this location, called the reference The reference plate should not be in contact with the ground. The distance between the reference plate and the ground should not be less than 1.5 meters. One side of the reference plate faces the sun, called the sunny side. The sunny side of the reference plate is rough and dark. On every day of the year, the most sufficient sunshine of the day that a flat panel can get in this place can be obtained, and the non-sun-facing side of the reference flat-panel is covered with thermal insulation material, and the temperature of the sunny side of the reference flat-panel will be obtained through real-time monitoring;

b2: Obtain the measured surface temperature data of the R cable structures at the surface points of the above R cable structures through real-time monitoring, and at the same time obtain the temperature distribution data of the previously defined cable structures along the thickness through real-time monitoring. The temperature data of the environment where the structure is located; through real-time monitoring, the temperature measured data series of the environment where the cable structure is located is obtained from the sunrise time of the day to 30 minutes after the sunrise time of the next day. The measured temperature data of the environment where the cable structure is located between the time and 30 minutes after sunrise of the next day are arranged in chronological order, and the highest temperature and the lowest temperature in the air temperature measurement data sequence of the environment where the cable structure is located are found. The maximum temperature difference in the air temperature measured data sequence minus the minimum temperature is the maximum temperature difference between the sunrise time of the day and 30 minutes after the sunrise time of the next day in the environment where the cable structure is located, which is called the maximum temperature difference of the environment, and is recorded as ΔT _emax ; The temperature measured data sequence of the environment where the cable structure is located is obtained through conventional mathematical calculations. The measured data series of the temperature of the sunny side of the reference plate between 30 minutes, the measured data series of the temperature of the sunny side of the reference plate from the sunrise time of the current day to the sunny side of the reference plate 30 minutes after the sunrise time of the next day The measured data of the temperature of the reference plate are arranged in chronological order, find the highest temperature and the lowest temperature in the measured data sequence of the temperature of the sunny side of the reference plate, and subtract the lowest temperature from the highest temperature in the measured data sequence of the temperature of the sunny side of the reference plate Temperature obtains the maximum temperature difference between the sunrise time of the day and 30 minutes after the sunrise time of the next day from the temperature of the sunny side of the reference plate, which is called the maximum temperature difference of the reference plate, and is recorded as ΔT _pmax ; The measured data series of cable structure surface temperature of all R cable structure surface points between 30 minutes after the sunrise time of the next day, there are R cable structure surface temperature measured data sequences of R cable structure surface points, each cable structure The measured data sequence of the surface temperature is arranged in chronological order by the measured data of the surface temperature of the cable structure between the sunrise time of the day and 30 minutes after the sunrise time of the next day at a surface point of the cable structure, and the measured data sequence of the surface temperature of each cable structure is found From the highest temperature and the lowest temperature in the data series, subtract the lowest temperature from the highest temperature in the measured data series of the surface temperature of each cable structure to obtain the temperature of each cable structure surface point from the sunrise time of the day to 30 minutes after the sunrise time of the next day If there are R surface points of the cable structure, there are R maximum temperature difference values between the sunrise time of the day and 30 minutes after the sunrise time of the next day, and the maximum value is called the maximum temperature difference of the cable structure surface, which is denoted as ΔT _smax ; From the measured data sequence of the surface temperature of each cable structure, the rate of change of the temperature of each cable structure surface point with respect to time is obtained through conventional mathematical calculations, and the temperature of each cable structure surface point with respect to time The rate of change also changes with time; after obtaining HBE "temperature distribution data along the thickness of the cable structure" at the same time between the sunrise time of the day and 30 minutes after the sunrise time of the next day through real-time monitoring, calculate the The difference between the maximum temperature and the minimum temperature in a total of BE "temperature distribution data of the cable structure along the thickness at the same altitude" at a selected altitude, the absolute value of this difference is called "thickness direction of the cable structure at the same altitude". If H different altitudes are selected, there will be H "maximum temperature differences in the thickness direction of the cable structure at the same altitude", and the maximum value of the H "maximum temperature differences in the thickness direction of the cable structure at the same altitude" is "The maximum temperature difference in the thickness direction of the cable structure", denoted as ΔT _tmax ;

b3: Measurement and calculation to obtain the steady-state temperature data of the cable structure; firstly, determine the moment to obtain the steady-state temperature data of the cable The time of the structural steady-state temperature data is between the sunset time of the current day and 30 minutes after the sunrise time of the next day. The sunset time refers to the meteorological sunset time determined according to the laws of the earth's rotation and revolution. The data can be queried or through conventional weather The required sunset time of each day can be obtained through scientific calculation; the second condition a condition is that during the period between the sunrise time of the current day and 30 minutes after the sunrise time of the next day, the maximum temperature difference ΔT _pmax and the maximum temperature difference of the reference plate The maximum temperature difference ΔT _smax on the surface of the cable structure is not greater than 5 degrees Celsius; the b condition of the second condition is that during the period between the sunrise of the day and 30 minutes after the sunrise of the next day, in the environment obtained by the previous measurement and calculation The maximum temperature difference ΔT _emax is not greater than the reference daily temperature difference ΔT _r , and the maximum temperature difference ΔT _pmax of the reference plate minus 2 degrees Celsius is not greater than ΔT _emax , and the maximum temperature difference ΔT _smax on the surface of the cable structure is not greater than ΔT _pmax ; only the second item a One of the condition and b condition is said to meet the second condition; the third condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the absolute value of the temperature change rate of the environment where the cable structure is located with respect to time is not greater than each 0.1 degrees Celsius per hour; the fourth condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the absolute value of the temperature change rate of each cable structure surface point in the R cable structure surface points with respect to time is not greater than 0.1 degrees Celsius per hour The fifth condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the measured data of the cable structure surface temperature of each cable structure surface point in the R cable structure surface points is from the sunrise time of the day to the day after the sunrise time of the next day The minimum value between 30 minutes; the sixth condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the "maximum temperature difference in the thickness direction of the cable structure" ΔT _tmax is not greater than 1 degree Celsius; this method utilizes the above six conditions, and the following Any one of the three kinds of time is called "mathematical time for obtaining the steady-state temperature data of the cable structure". Item 1 to item 5 conditions, the second type of time is the time that only meets the sixth condition in the above "conditions related to the time to determine the time to obtain the steady-state temperature data of the cable structure", and the third type of time is when the above-mentioned conditions are met at the same time The moment of the first item to the sixth condition in "Conditions related to the moment of determining the time to obtain the steady-state temperature data of the cable structure"; At one moment, the moment of obtaining the steady-state temperature data of the cable structure is the mathematical moment of obtaining the steady-state temperature data of the cable structure; if the mathematical moment of obtaining the steady-state temperature data of the cable structure is not any moment in the actual recording data moment in this method, Then take this method closest to the mathematical time of obtaining the steady-state temperature data of the cable structure The actual recorded data moment is the moment when the steady-state temperature data of the cable structure is obtained; this method will use the measured and recorded quantity at the moment when the steady-state temperature data of the cable structure is obtained to perform cable structure-related health monitoring analysis; this method approximately considers that the obtained The temperature field of the cable structure at the moment of the steady-state temperature data of the cable structure is in a steady state, that is, the temperature of the cable structure at this moment does not change with time, and this moment is the "moment of obtaining the steady-state temperature data of the cable structure" of this method; Heat transfer characteristics of the structure, using the “measured surface temperature data of R cable structures” and “measured temperature data of HBE cable structures along the thickness” at the moment when the steady-state temperature data of the cable structure is obtained, and using the heat transfer calculation model of the cable structure, through The temperature distribution of the cable structure at the moment of obtaining the steady-state temperature data of the cable structure is obtained by conventional heat transfer calculation. At this time, the temperature field of the cable structure is calculated according to the steady state. The temperature distribution data of the structure includes the calculated temperature of the R cable structure surface points on the cable structure, and the calculated temperature of the R cable structure surface points is called the R cable structure steady-state surface temperature calculation data, and also includes the previously selected cable structure The calculated temperature of the HBE "points for measuring the temperature distribution data of the cable structure along the thickness", and the calculated temperature of the HBE "points for measuring the temperature distribution data of the cable structure along the thickness" are called "calculated data of the temperature of the HBE cable structure along the thickness" , when the measured surface temperature data of the R cable structures is equal to the calculated data of the steady-state surface temperature of the R cable structures, and the "measured data of the temperature along the thickness of the HBE cable structures" corresponds to the "calculated data of the temperature along the thickness of the HBE cable structures". When they are equal, the calculated temperature distribution data of the cable structure at the moment when the cable structure steady-state temperature data is obtained is called "cable structure steady-state temperature data" in this method, and the "R cable structure surface temperature measured data " is called "the measured data of the steady-state surface temperature of R cable structures", and "the measured data of the temperature of the HBE cable structures along the thickness" is called "the measured data of the steady-state temperature of the HBE cable structures along the thickness"; When "R cable structure surface points", the number and distribution of "R cable structure surface points" must meet three conditions. The first condition is that when the cable structure temperature field is in a steady state, when any point on the cable structure surface When the temperature of is obtained by the linear interpolation of the measured temperature of the point adjacent to the arbitrary point on the surface of the cable structure among the "R cable structure surface points", the temperature of the arbitrary point on the surface of the cable structure obtained by linear interpolation is the same as that of the surface of the cable structure The error of the actual temperature at this arbitrary point is not greater than 5%; the cable structure surface includes the supporting cable surface; the second condition is that the number of points at the same altitude in the "R cable structure surface points" is not less than 4, and " The points at the same altitude in the "R cable structure surface points" are uniformly distributed along the cable structure surface; The maximum value Δh among the values is not greater than the value obtained by dividing ΔT _h by 0.2°C. For the convenience of description, the unit of ΔT _h is ℃/m, and for the convenience of description, the unit of Δh is m;" The definition of two adjacent cable structure surface points along the altitude of "R cable structure surface points" means that when only the altitude is considered, there is no cable structure surface point in the "R cable structure surface points". The altitude value of the surface point is between the altitude values of two adjacent cable structure surface points; the third condition is to query or calculate according to meteorological routines to obtain the sunshine law of the cable structure location and the altitude interval, and then according to the cable structure According to the geometric characteristics and orientation data of the structure, find the positions of those surface points on the cable structure that receive the most sunshine time throughout the year, and at least one cable structure surface point in the "R cable structure surface points" is on the cable structure that is exposed to sunlight throughout the year. one of those surface points at which the hours of sunshine are greatest;

c. According to the "temperature measurement and calculation method of the cable structure of this method", the steady-state temperature data of the cable structure in the initial state is directly measured and calculated, and the steady-state temperature data of the cable structure in the initial state is called the initial steady-state temperature data of the cable structure. It is recorded as "initial cable structure steady-state temperature data vector T _o "; the physical and mechanical performance parameters of various materials used in the cable structure _that vary with temperature are obtained from actual measurements or information; At the same moment when the steady-state temperature data vector T _o of the initial cable structure is obtained, the measured data of the initial cable structure is directly measured and calculated. The measured data of the initial cable structure includes the concentrated load measurement data of the cable structure, the distributed load measurement data of the cable structure, Cable structure body load measurement data, initial values of all monitored quantities, initial cable force data of all supporting cables, initial cable structure modal data, initial cable structure strain data, initial cable structure geometric data, initial cable structure support generalized coordinates The measured data including initial cable structure angle data and initial cable structure spatial coordinate data, the initial cable structure support generalized coordinate data include initial cable structure support spatial coordinate data and initial cable structure support angular coordinate data, after At the same time as the actual measurement data of the cable structure, the data that can express the health state of the support cable including the non-destructive testing data of the support cable are measured and calculated. At this time, the data that can express the health state of the support cable is called the initial health state of the support cable data; the initial values of all monitored quantities form the initial value vector C _o of the monitored quantity, and the numbering rule of the initial value vector C _o of the monitored quantity is the same as that of the M monitored quantities; Structural load measurement data establishes the initial damage vector d _o of the evaluated object, and the vector d _o represents the initial health state of the evaluated object of the cable structure represented by the initial mechanical calculation benchmark model A _o ; the elements of the initial damage vector d _o of the evaluated object The number is equal to N, the elements of d _o have a one-to-one correspondence with the evaluated object, and the numbering rules of the elements of the vector d _o are the same as the numbering rules of the evaluated object; if a certain element of d _o corresponds to the evaluated object is the index system A support cable in , then the value of this element of d _o represents the initial damage degree of the corresponding support cable. If the value of this element is 0, it means that the support cable corresponding to this element is intact and has no damage. If If the value is 100%, it means that the supporting cable corresponding to this element has completely lost its bearing capacity; if its value is between ₀ and 100%, it means that the supporting cable has lost its corresponding proportion of bearing capacity; The evaluated object corresponding to an element is a certain load. In this method, the value of the element of d _o is 0, which means that the initial value of the change of this load is 0; When the data of the healthy state of the structure, or it can be considered that the initial state of the structure is a state of no damage and no relaxation, the value of each element related to the supporting cable in the vector d _o is 0; the initial cable structure support angular coordinate data constitutes the initial cable knot Structural support angular coordinate vector U _o ;

d. According to the design drawing of the cable structure, the as-built drawing and the actual measurement data of the initial cable structure, the initial health status data of the supporting cable, the measurement data of the concentrated load of the cable structure, the measurement data of the distributed load of the cable structure, the measurement data of the body load of the cable structure, and the data of the cable structure. The physical and mechanical performance parameters of the various materials used vary with temperature, the initial cable structure support angular coordinate vector U _o , the initial cable structure steady-state temperature data vector T _o and all the cable structure data obtained in the previous steps, to establish the calculation The initial mechanical calculation benchmark model A _o of the cable structure is entered into the "steady-state temperature data of the cable structure". The calculated data of the cable structure based on A _o must be very close to the measured data, and the difference between them shall not be greater than 5%; corresponding to A _o The "cable structure steady-state temperature data" is the "initial cable structure steady-state temperature data vector T _o "; the cable structure support angular coordinate data corresponding to A _o is the initial cable structure support angular coordinate vector U _o ; corresponding to A The health status of the evaluated object of _o is represented by the initial damage vector d _o of the evaluated object; the initial values of all monitored quantities corresponding to A _o are represented by the initial value vector C _o of the monitored quantities; U _o , T _o and d _o are The parameters of A _o , the initial values of all the monitored quantities obtained from the mechanical calculation results of A _o are the same as the initial values of all the monitored quantities represented by C _o , so it can also be said that C _o is composed of the mechanical calculation results of A _o , In this method, A _o , C _o , d _o , U _o and T _o are unchanged;

e. In this method, except where the letter i clearly indicates the step number, the letter i only indicates the number of cycles, that is, the i-th cycle; the current initial value of the cable structure that needs to be established or has been established at the beginning of the i-th cycle The mechanical calculation benchmark model is recorded as the current initial mechanical calculation benchmark model A ⁱ _o , A _o and A ⁱ _o include temperature parameters, and the influence of temperature changes on the mechanical properties of the cable structure can be calculated; at the beginning of the i-th cycle, corresponding to A The "cable structure steady-state temperature data" of ⁱ _o is represented by the current initial cable structure steady-state temperature data vector T ⁱ _o , the definition of vector T ⁱ _o is the same as that of vector T _o , and the elements of T ⁱ _o are the same as T _o The elements of are in one-to-one correspondence; at the beginning of the i-th cycle, the "cable structure support angular coordinate data" corresponding to A ⁱ _o is represented by the current initial cable structure support angular coordinate vector U ⁱ _o , and the definition method of vector U ⁱ _o In the same way as the definition of the vector U _o , the elements of U ⁱ _o correspond to the elements of U _o one by one; the current initial damage vector of the evaluated object required at the beginning of the i-th cycle is recorded as d ⁱ _o , and d ⁱ _o represents the At the beginning of the cycle, the health status of the evaluated object of the search structure A ⁱ _o is defined. The definition of d ⁱ _o is the same as that of d _o , and the elements of d ⁱ _o correspond to the elements of d _o one by one; when the i-th cycle starts , the initial values of all the monitored quantities are represented by the current initial value vector C ⁱ _o of the monitored quantity. The definition method of the vector C ⁱ _o is the same as that of the vector C _o , and the elements of C ⁱ _o are one by one with the elements of C _o Correspondingly, the current initial value vector C ⁱ _o of the monitored quantity represents the specific values of all the monitored quantities corresponding to A ⁱ _o ; U ⁱ _o , T ⁱ _o and d ⁱ _o are the characteristic parameters of A ⁱ _o , and C ⁱ _o is determined by A ⁱ _o is composed of mechanical calculation results; at the beginning of the first cycle, A ⁱ _o is recorded as A ¹ _o , and the method of establishing A ¹ _o is to make A ¹ _o equal to A _o ; at the beginning of the first cycle, T ⁱ _o Denote it as T ¹ _o , the method of establishing T ¹ _o is to make T ¹ _o equal to T _o ; at the beginning of the first cycle, U ⁱ _o is recorded as U ¹ _o , and the method of establishing U ¹ _o is to make U ¹ _o equal to U _o ; at the beginning of the first cycle, d ⁱ _o is recorded as d ¹ _o , and the method of establishing d ¹ _o is to make d ¹ _o equal to d _o ; at the beginning of the first cycle, C ⁱ _o is recorded as C ¹ _o , and the establishment The method of C ¹ _o is to make C ¹ _o equal to C _o ;

f. From here, enter the cycle from step f to step q; during the service process of the structure, according to "the temperature measurement and calculation method of the cable structure of this method", the current data of the steady-state temperature data of the cable structure are continuously measured and calculated, and all The current data of "cable structure steady-state temperature data" constitutes the current cable structure steady-state temperature data vector T ⁱ , the definition method of vector T ⁱ is the same as that of vector T _o , and the elements of T ⁱ correspond to the elements of T _o one by one ; At the same moment when the current steady-state temperature data vector T ⁱ of the cable structure is obtained from the actual measurement, the current data of the angular coordinates of the cable structure supports are obtained from the actual measurement, and all the current data of the angular coordinates of the cable structure supports form the vector U ⁱ , the vector U ⁱ is defined in the same way as the vector U _o ; when the vector T ⁱ is obtained from the actual measurement, all the cable structures in the cable structure at the same time when the current cable structure steady-state temperature data vector T ⁱ is obtained The current value of the monitored quantity. All these values form the current value vector C ⁱ of the monitored quantity. The definition method of the vector C ⁱ is the same as that of the vector C _o . The elements of C ⁱ correspond to the elements of C _o one by one, indicating that the same The value of the monitored quantity at different times;

g. According to the measured support angle coordinate vector U ⁱ of the current cable structure and the current steady-state temperature data vector T ⁱ of the cable structure, follow steps g1 to g3 to update the current initial mechanical calculation benchmark model A ⁱ _o and the current initial value vector C of the monitored quantity ⁱ _o , the current initial cable structure steady-state temperature data vector T ⁱ _o and the current initial cable structure support angular coordinate vector U ⁱ _o , while the current initial damage vector d ⁱ _o of the evaluated object remains unchanged;

g1. Compare T ⁱ and T ⁱ _o , U ⁱ and U ⁱ _o respectively, if T ⁱ is equal to T ⁱ _o and U ⁱ is equal to U ⁱ _o , there is no need to compare A ⁱ _o , U ⁱ _o , C ⁱ _o and T ⁱ _o is updated, otherwise A ⁱ _o , U ⁱ _o , C ⁱ _o and T ⁱ _o need to be updated according to the following steps;

g2. Calculate the difference between U ⁱ and U _o . The difference between U ⁱ and U _o is the support angular displacement of the cable structure support with respect to the initial position. Use the support angular displacement vector V to represent the support angular displacement, and V is equal to U ⁱ minus Remove U _o ; calculate the difference between T ⁱ and T _o , the difference between T ⁱ and T _o is the change of the current cable structure steady-state temperature data with respect to the initial cable structure steady-state temperature data, the difference between T ⁱ and T _o is the steady-state temperature The change vector S indicates that S is equal to T ⁱ minus T _o , and S indicates the change of the steady-state temperature data of the cable structure;

g3. First apply the support angular displacement constraint to the support of the cable structure in A _o , the value of the support angular displacement constraint is taken from the value of the corresponding element in the support angular displacement vector V, and then impose a constraint on the cable structure in A _o The temperature change, the value of the applied temperature change is taken from the steady-state temperature change vector S, and the current initial mechanical calculation benchmark model is updated after applying the support angular displacement constraint to the cable structure support in A _o and applying the temperature change to the cable structure A ⁱ _o , while updating A ⁱ _o , all element values of U ⁱ _o are also replaced by corresponding values of all elements of U ⁱ , that is, U ⁱ _o is updated, and all element values of T ⁱ _o are also replaced by corresponding values of all elements of T ⁱ , that is, T ⁱ _o is updated, so that U ⁱ _o and T ⁱ _o corresponding to A ⁱ _o are obtained correctly, and d ⁱ _o remains unchanged at this time; when A ⁱ _o is updated, the index of A ⁱ _o The health status is represented by the current initial damage vector d ⁱ _o of the evaluated object, the steady-state temperature of the cable structure of A ⁱ _o is represented by the current data vector T ⁱ _o of the steady-state temperature of the cable structure, and the support angle coordinates of A ⁱ _o are represented by the current initial cable The structural support angular coordinate vector U ⁱ _o represents; the method of updating C ⁱ _o is: after updating A ⁱ _o , obtain the current specific values of all monitored quantities in A ⁱ _o through mechanical calculations, and these specific values form C ⁱ _o ;

h. On the basis of the current initial mechanical calculation benchmark model A ⁱ _o , perform several mechanical calculations according to steps h1 to h4, and establish the numerical change matrix ΔC ⁱ of the monitored quantity of damage per unit and the unit change vector D ⁱ of the evaluated object through calculation _u ;

h1. At the beginning of the ith cycle, directly obtain ΔC ⁱ and D ⁱ _u according to the methods listed in step h2 to step h4; at other times, after updating A ⁱ _o in step g, you must follow steps h2 to h4 The method listed in step h4 regains ΔC ⁱ and D ⁱ _u , if A ⁱ _o is not updated in step g, then directly transfer to step i for follow-up work here;

h2. Carry out several mechanical calculations on the basis of the current initial mechanical calculation benchmark model A ⁱ _o . The number of calculations is numerically equal to the number N of all evaluated objects. There are N evaluation objects and there are N calculations; Numbering rules, calculations are performed sequentially; each calculation assumes that there is only one evaluated object, and the unit damage or load unit change is added on the basis of the original damage or load. Specifically, if the evaluated object is a supporting cable in the cable system , then it is assumed that the support cable will increase the unit damage, if the evaluated object is a load, it is assumed that the load will increase the load unit change, and record the increased unit damage or load unit change with D ⁱ _uk , where k represents Increment the number of the assessed object for unit damage or load unit change, D ⁱ _uk is an element of the assessed object unit change vector D ⁱ _u , the numbering rule of the elements of the assessed object unit change vector D ⁱ _u is the same as that of the vector d _o The numbering rules of the elements are the same; the evaluated object with additional unit damage or load unit change in each calculation is different from the evaluated object with additional unit damage or load unit change in other calculations, and each calculation uses the mechanical method to calculate the index The current calculated values of all the monitored quantities of the structure, the current calculated values of all the monitored quantities obtained by each calculation form a current vector of the monitored quantities calculation; when it is assumed that the kth assessed object is added with unit damage or load unit change , use C ⁱ _tk to represent the corresponding "monitored quantity calculation current vector"; when numbering the elements of each vector in this step, the same numbering rule should be used with other vectors in this method to ensure that the elements in each vector in this step Any element, with the elements of the same number in other vectors, expresses the relevant information of the same monitored quantity or the same object; the definition of C ⁱ _tk is the same as that of the vector C _o , and the elements of C ⁱ _tk are the same as C The elements of _o correspond one-to-one;

h3. The vector C ⁱ _tk obtained by each calculation is subtracted from the vector C ⁱ _o to obtain a vector, and then each element of the vector is divided by the value of unit damage or load unit change assumed in this calculation to obtain a "being The numerical change vector of the monitored quantity δC ⁱ _k "; if there are N evaluated objects, there are N "numerical change vectors of the monitored quantity";

h4. From these N "value change vectors of monitored quantities" according to the numbering rules of N evaluated objects, a "monitored quantity numerical change matrix ΔC ⁱ " with N columns is formed in turn; the numerical value of monitored quantities per unit damage Each column of the change matrix ΔC ⁱ corresponds to a unit change vector of the monitored quantity; each row of the value change matrix ΔC ⁱ of the unit damage monitored quantity corresponds to the same monitored quantity when the unit damage or the load unit changes when different evaluated objects different unit change ranges; the numbering rules of the columns of the unit damage monitored quantity numerical change matrix ΔC ⁱ are the same as the numbering rules of the elements of the vector d _o , and the numbering rules of the rows of the unit damage monitored quantity numerical change matrix ΔC ⁱ are the same as M The numbering rules of the monitored quantities are the same;

i. Define the current nominal damage vector d ⁱ _c and the current actual damage vector d ⁱ , the number of elements of d ⁱ _c and d ⁱ is equal to the number of evaluated objects, and the distance between the elements of d ⁱ _c and d ⁱ and the evaluated object is One-to-one correspondence, the element value of d ⁱ _c represents the nominal damage degree or nominal load variation of the corresponding evaluated object, d ⁱ _c and d ⁱ are the same as the element numbering rules of the initial damage vector d _o of the evaluated object, d ⁱ _c The elements of , the elements of d ⁱ and the elements of d _o are in one-to-one correspondence;

j. According to the relationship between the current numerical vector C ⁱ of the monitored quantity and the "current initial numerical vector C ⁱ _o of the monitored quantity", "the numerical change matrix of the monitored quantity with unit damage ΔC ⁱ ", and "the current nominal damage vector d ⁱ _c " Approximate linear relationship, the approximate linear relationship can be expressed as formula 1. In formula 1, other quantities except d ⁱ _c are known, and the current nominal damage vector d ⁱ _c can be calculated by solving formula 1;

Formula 1

k. The kth element d ⁱ _k of the current actual damage vector d ⁱ expressed by formula 2 is the same as the kth element d i ok of the current initial damage vector d ⁱ _o of the evaluated object and the kth element d ⁱ _ok of the current nominal damage vector d ⁱ _c The relationship among k elements d ⁱ _ck is calculated to obtain all the elements of the current actual damage vector d ⁱ ;

In formula 2, k=1,2,3,...,N; d ⁱ _k represents the current actual health status of the kth evaluated object in the i-th cycle, if the evaluated object is a support in the cable system Then d ⁱ _k represents its current actual damage. When d ⁱ _k is 0, it means no damage. When it is 100%, it means that the supporting cable completely loses its bearing capacity. When it is between 0 and 100%, it means that it loses the corresponding proportion of bearing capacity. Ability, so far this method realizes the identification of the health status of the core evaluated object;

l. After obtaining the current nominal damage vector d ⁱ _c , establish the identification vector B ⁱ according to formula 3, and formula 4 gives the definition of the kth element of the identification vector B ⁱ ;

Formula 3

Formula 4

In formula 4, the element B ⁱ _k is the kth element of the identification vector B ⁱ , D ⁱ _uk is the kth element of the unit change vector D ⁱ _u of the evaluated object, d ⁱ _ck is the current nominal damage vector d ⁱ of the evaluated object The kth element of _c , they all represent the relevant information of the kth evaluated object, k=1,2,3,...,N in formula 4;

m. If the elements of the identification vector B ⁱ are all 0, then get back to step f to continue this cycle; if the elements of the identification vector B ⁱ are not all 0, then enter the next step, namely step n;

n. Calculate each element of the current initial damage vector d ⁱ⁺¹ _o of the evaluated object required for the next, ie i+1th cycle, according to formula 5;

In formula 5, d ⁱ⁺¹ _ok is the kth element of the current initial damage vector d ⁱ⁺¹ _o of the evaluated object required for the next cycle, that is, the i+1th cycle, and d ⁱ _ok is this time, that is, the ith The k-th element of the current initial damage vector d ⁱ _o of the evaluated object in the second cycle, D ⁱ _uk is the k-th element of the unit change vector D ⁱ _u of the evaluated object in the i-th cycle, and B ⁱ _k is the i-th The kth element of the cyclic identification vector B ⁱ , k=1,2,3,...,N in formula 5;

o. On the basis of the initial mechanical calculation benchmark model A _o , the support angular displacement constraint is first imposed on the cable structure support in A _o , and the value of the support angular displacement constraint is taken from the corresponding element in the support angular displacement vector V value, and then apply a temperature change to the cable structure in A _o , the value of the applied temperature change is taken from the steady-state temperature change vector S, and then let the health status of the cable be d ⁱ⁺¹ _o to get the next time, That is, the mechanical calculation benchmark model A ⁱ⁺¹ required for the i+1th cycle; after obtaining A ⁱ⁺¹ , obtain the current specific values of all monitored quantities in A ⁱ⁺¹ through mechanical calculations, and these specific values consist of The current initial value vector C ⁱ⁺¹ _o of the monitored quantity required for the next cycle, that is, the i+1th cycle;

p. Take the current initial cable structure steady-state temperature data vector T ⁱ⁺¹ _o required for the next cycle, that is, the i+1th cycle, which is equal to the current initial cable structure steady-state temperature data vector T ⁱ _o of the i-th cycle; The current initial cable structure support angular coordinate vector U ⁱ⁺¹ _o required for the i+1th cycle is equal to the current initial cable structure support angular coordinate vector U ⁱ _o of the ith cycle;

q. Go back to step f and start the next cycle.

Beneficial effects: the structural health monitoring system first uses sensors to monitor the structural response on-line for a long time, and then analyzes the monitoring data online (or offline) to obtain the structural health status data. Due to the complexity of the structure, the structural health monitoring system needs to use A large number of sensors and other equipment are used for structural health monitoring, so the cost is usually quite high, so the cost problem is a major problem restricting the application of structural health monitoring technology. On the other hand, the correct identification of the health status of the core assessed objects (such as stay cables) is an integral part of, or even the whole of, the correct identification of the structural health status, while the secondary assessed objects (such as structural bearing The correct identification of changes in the load (such as changes in the number and mass of cars passing a cable-stayed bridge) has little or no effect on the correct identification of the state of health of the cable structure. However, the number of secondary evaluated objects is usually equal to the number of core evaluated objects, and the number of secondary evaluated objects is often greater than the number of core evaluated objects, so that the number of evaluated objects is often the number of core evaluated objects multiple times the number. When the secondary evaluated object (load) changes, in order to accurately identify the core evaluated object, the conventional method requires that the quantity of the monitored quantity (measured using sensors and other equipment) must be greater than or equal to the number of evaluated objects. When the number of secondary assessment objects is relatively large (in fact, it is often the case), the number of sensors and other equipment required by the structural health monitoring system is very large, so the cost of the structural health monitoring system will become very high, even high unacceptable. The inventors have found that the changes in the secondary evaluated objects (such as the normal load of the structure, the normal load of the structure means that the load that the structure is bearing does not exceed the structural allowable load defined in the structural design document or the structural completion document) are relatively small. Hours (For loads, the structure only bears normal loads. Whether the loads borne by the structure are normal loads can be determined by visual inspection. , the structure is only subjected to normal loads), the magnitude of the change in the structural response caused by them (this specification is called "secondary response") is much smaller than that caused by the change of the core assessed object (such as damage to the support cable) The magnitude of change in the response (this specification calls it "core response"), the sum of the secondary response and the core response is the total change in the structural response (this specification calls it the "overall response"), obviously the core response occupies the overall response Based on this, the inventor found that when determining the number of monitored quantities, even if a value slightly larger than the number of core evaluated objects is selected, but far smaller than the number of evaluated objects (this method is done in this way), that is to say, even if A relatively small number of sensors and other equipment can still accurately obtain the health status data of the core assessed objects and meet the core needs of structural health status monitoring. Therefore, the cost of the structural health monitoring system proposed by this method is obviously higher than that required by conventional methods. The cost of the structural health monitoring system is much lower, that is to say, this method can realize the evaluation of the health status of the core evaluated object of the cable structure at a much lower cost. Adoption is pivotal.

Detailed ways

The method employs an algorithm for identifying the health status of core assessed subjects. During specific implementation, the following steps are one of various steps that may be taken.

Step 1: First identify the amount of possible varying loads that the cable structure will be subjected to. According to the characteristics of the loads borne by the cable structure, confirm "all the loads that may change", or regard all the loads as "all the loads that may change", let there be a total of JZW loads that may change, that is, a total of JZW A secondary object to be evaluated. Assume that there are M ₁ supporting cables in the cable system, that is, there are M ₁ core objects to be evaluated. Let the sum of the number of supporting cables of the cable structure and the number of JZW "all possible changing loads" be N, that is, there are N evaluated objects. Consecutively number the evaluated objects, which will be used to generate vectors and matrices in subsequent steps.

"All the monitored spatial coordinate data of the structure" is described by the spatial coordinates of K specified points on the structure and L specified directions of each specified point. The change of the structural space coordinate data is all the spatial coordinates of the K specified points Changes in coordinate components. Each time there are M (M=K×L) space coordinate measured values or calculated values to represent the structural space coordinate information. Based on the above-mentioned monitored quantities, there are M monitored quantities in the entire cable structure, and M must not be less than the number of core assessed objects plus 4.

For convenience, in this method, "all monitored parameters of the cable structure" are referred to as "monitored quantities" for short. Number the M monitored quantities consecutively, and this number will be used to generate vectors and matrices in subsequent steps. The method uses variable j to denote this number, j=1,2,3,...,M.

Determine the "temperature measurement and calculation method of the cable structure of this method" according to the steps specified in the technical scheme and claims.

The second step: establish the initial mechanical calculation benchmark model A _o .

When the cable structure is completed, or before the establishment of the health monitoring system, the "cable structure steady-state temperature data" can be measured and calculated according to the "temperature measurement and calculation method of the cable structure of this method" (it can be measured by conventional temperature measurement methods, such as using Thermal resistance measurement), the "cable structure steady-state temperature data" at this time is represented by a vector T _o , which is called the initial cable structure steady-state temperature data vector T _o . While T _o is obtained by actual measurement, the initial values of all monitored quantities of the cable structure are directly measured and calculated by conventional methods, and the initial value vector C _o of the monitored quantities is formed.

In this method, the following method can be used to measure and calculate a certain measured quantity and monitored quantity (for example, a cable structure) at the same moment when a certain (such as initial or current, etc.) cable structure steady-state temperature data vector is obtained. All monitored quantities of the structure) data: while measuring and recording the temperature (including the air temperature of the environment where the cable structure is located, the temperature of the sunny side of the reference plate and the surface temperature of the cable structure), for example, measuring and recording the temperature every 10 minutes, then At the same time, the data of a certain measured quantity and monitored quantity (such as all monitored quantities of the cable structure) are also measured and recorded every 10 minutes. Once the time to obtain the steady-state temperature data of the cable structure is determined, the data of a certain measured quantity and monitored quantity (for example, all monitored quantities of the cable structure) at the same time as the time when the steady-state temperature data of the cable structure is obtained is called At the same moment when the steady-state temperature data of the cable structure is obtained, the data of a certain measured quantity and a certain monitored quantity obtained by a certain method are measured by a certain method.

The temperature-dependent physical parameters (such as thermal expansion coefficient) and mechanical performance parameters (such as elastic modulus and Poisson's ratio) of various materials used in the cable structure are obtained by conventional methods (research information or actual measurement).

While T _o is obtained by actual measurement, the actual measurement and calculation data of the cable structure are obtained by actual measurement and calculation using conventional methods. The measured and calculated data of the cable structure includes the non-destructive testing data of the supporting cable and other data that can express the health state of the cable, the initial geometric data of the cable structure, the data of the cable force, the data of the pulling force of the tie rod, the generalized coordinate data of the initial cable structure support (including the support about The spatial and angular coordinates of the X, Y, and Z axes of the Cartesian Cartesian coordinate system (that is, the initial cable structure support space coordinate data and the initial cable structure support angular coordinate data), the concentrated load measurement data of the cable structure, and the distributed load measurement data of the cable structure , Cable structure body load measurement data, cable structure modal data, structural strain data, structural angle measurement data, structural space coordinate measurement data and other measured data. The initial cable structure support angular coordinate data constitute the initial cable structure support angular coordinate vector U _o . The initial geometric data of the cable structure can be the spatial coordinate data of all cable end points plus the spatial coordinate data of a series of points on the structure, the purpose is to determine the geometric characteristics of the cable structure according to these coordinate data. For cable-stayed bridges, the initial geometric data can be the spatial coordinate data of all cable end points plus the spatial coordinate data of several points on both ends of the bridge, which is the so-called bridge type data. Use the non-destructive testing data of supporting cables and other data that can express the health status of the supporting cables and the load measurement data of the cable structure to establish the initial damage vector d _o of the evaluated object, and use d _o to represent the cable structure (represented by the initial mechanical calculation benchmark model A _o ) The initial health status of the evaluated object. If there is no non-destructive testing data of the supporting cable and other data that can express the health state of the supporting cable, or when the initial state of the structure can be considered as a state of no damage and no relaxation, the value of each element related to the supporting cable in the vector d _o is set to 0 , if a certain element of d _o corresponds to a certain load, the value of this element of d _o is taken as 0 in this method, which means that the initial value of the change of this load is 0. Utilize the design drawing, as-built drawing of the cable structure and the measured data of the initial cable structure, the non-destructive testing data of the supporting cable, the physical and mechanical performance parameters of various materials used in the cable structure as a function of temperature, and the angular coordinates of the initial cable structure support The vector U _o and the initial cable structure steady-state temperature data vector T _o are incorporated into the "cable structure steady-state temperature data" using mechanical methods (such as finite element method) to establish the initial mechanical calculation benchmark model A _o .

No matter what method is used to obtain the initial mechanical calculation benchmark model A _o , the cable structure calculation data calculated based on A _{o must} be very Close to the measured data, the error is generally not greater than 5%. In this way, the calculation data of cable force, strain, shape and displacement of cable structure, angle data of cable structure, space coordinate data of cable structure and so on under the simulated situation obtained by A _o calculation can be reliably close to the simulated situation The measured data when it actually happened. The health state of the supporting cable in the model A _o is represented by the initial damage vector d _o of the evaluated object, and the steady-state temperature data of the cable structure is represented by the initial cable structure steady-state temperature data vector T _o . Since the calculated values of all monitored quantities calculated based on A _o are very close to the initial values of all monitored quantities (obtained from actual measurements), it can also be used on the basis of A _o to perform mechanical calculations, and each monitored quantity of A _o The calculated numerical value of the monitored quantity constitutes the initial numerical vector C _o of the monitored quantity. The "cable structure steady-state temperature data" corresponding to A _o is the "initial cable structure steady-state temperature data vector T _o "; the health state of the evaluated object corresponding to A _o is represented by the initial damage vector d _o of the evaluated object; The initial values of all the monitored quantities of A _o are represented by the initial value vector C _o of the monitored quantities. The angular coordinate data of the cable structure support corresponding to A _o is represented by the initial cable structure support angular coordinate vector U _o ; T _o , U _o and d _o are the parameters of A _o , and C _o is composed of the mechanical calculation results of A _o .

The third step: in this method, except the place where the letter i clearly represents the step number, the letter i only represents the number of cycles, i.e. the ith cycle; The current initial mechanical calculation benchmark model is denoted as the current initial mechanical calculation benchmark model A ⁱ _o , A _o and A ⁱ _o include temperature parameters, and the influence of temperature changes on the mechanical properties of the cable structure can be calculated; at the beginning of the i-th cycle, the corresponding The "cable structure steady-state temperature data" in A ⁱ _o is represented by the current initial cable structure steady-state temperature data vector T ⁱ _o , the definition of vector T ⁱ _o is the same as that of vector T _o , and the elements of T ⁱ _o are the same as The elements of T _o are in one-to-one correspondence; at the beginning of the i-th cycle, the cable structure support angular coordinate data corresponding to the current initial mechanical calculation benchmark model A ⁱ _o of the cable structure constitutes the current initial cable structure support angular coordinate vector U ⁱ _o , when the current initial mechanical calculation benchmark model A ⁱ _o of the cable structure is established for the first time, U ⁱ _o is equal to U _o . The current initial damage vector of the evaluated object required at the beginning of the i-th cycle is denoted as d ⁱ _o , d ⁱ _o represents the health status of the evaluated object of the cable structure A ⁱ _o at the beginning of the cycle, and the definition of d ⁱ _o is the same as d _o is defined in the same way, and the elements of d ⁱ _o correspond to the elements of d _o one by one; at the beginning of the i-th cycle, the initial values of all monitored quantities are represented by the current initial value vector C ⁱ _o of the monitored quantity, and the vector The definition method of C ⁱ _o is the same as the definition method of vector C _o , the elements of C ⁱ _o correspond to the elements of C _o one by one, and the current initial value vector C ⁱ _o of the monitored quantity represents all the monitored quantities corresponding to A ⁱ _o The specific value of ; T ⁱ _o and d ⁱ _o are the characteristic parameters of A ⁱ _o ; C ⁱ _o is composed of the mechanical calculation results of A ⁱ _o ; at the beginning of the first cycle, A ⁱ _o is recorded as A ¹ _o , and A The method of ¹ _o is to make A ¹ _o equal to A _o ; at the beginning of the first cycle, T ⁱ _o is recorded as T ¹ _o , and the method of establishing T ¹ _o is to make T ¹ _o equal to T _o ; at the beginning of the first cycle , U ⁱ _o is recorded as U ¹ _o , the method of establishing U ¹ _o is to make U ¹ _o equal to U _o ; at the beginning of the first cycle, d ⁱ _o is recorded as d ¹ _o , and the method of establishing d ¹ _o is to make d ¹ _o is equal to d _o ; at the beginning of the first cycle, C ⁱ _o is recorded as C ¹ _o , and the method of establishing C ¹ _o is to make C ¹ _o equal to C _o .

Step 4: Install the hardware part of the cable structure health monitoring system. The hardware part includes at least: the monitored quantity monitoring system (for example, including space coordinate measurement system, signal conditioner, etc.), the cable structure support angular coordinate monitoring system (including angle measurement sensor, signal conditioner, etc.), cable structure temperature monitoring system ( Including temperature sensor, signal conditioner, etc.) and cable structure environment temperature measurement system (including temperature sensor, signal conditioner, etc.), signal (data) collector, computer and communication alarm equipment. Every monitored quantity, every bearing angular coordinate of the cable structure, and every temperature must be monitored by the monitoring system, and the monitoring system transmits the monitored signal to the signal (data) collector; the signal is transmitted to the computer; the computer is responsible for running the health monitoring software of the evaluated object of the cable structure, including recording the signal transmitted by the signal collector; (or) designated personnel to call the police.

The 5th step: compile and install and run the system software of this method on the computer, this software will finish the functions such as monitoring, record, control, storage, computing, notification, alarm that this method task needs (that is all in this specific implementation method work that can be done with a computer).

Step 6: This step starts the cycle operation. During the service process of the structure, the current data of the steady-state temperature data of the cable structure are obtained through continuous actual measurement and calculation according to the "temperature measurement and calculation method of the cable structure of this method". All "cable structure steady-state The current data of "Temperature Data" form the current steady-state temperature data vector T ⁱ of the cable structure. The definition of the vector T ⁱ is the same as that of the vector T _o , and the elements of T ⁱ correspond to the elements of T _o one by one; At the same time as T ⁱ , the current values of all monitored quantities in the cable structure are actually measured, and all these values form the current value vector C ⁱ of the monitored quantity. The definition of vector C ⁱ is the same as that of vector C _o . The elements of C ⁱ One-to-one correspondence with the elements of C _o , indicating the value of the same monitored quantity at different times.

While the vector T ⁱ is obtained from the actual measurement, the current data of the angular coordinates of the cable structure support are obtained from the actual measurement, and all the data form the vector U ⁱ of the measured support angular coordinates of the current cable structure.

Step 7: After obtaining the measured support angle coordinate vector U ⁱ of the current cable structure and the steady-state temperature data vector T ⁱ of the current cable structure, compare U ⁱ with U ⁱ _o , T ⁱ and T ⁱ _o respectively, if U ⁱ is equal to U ⁱ _o and T ⁱ is equal to T ⁱ _o , then there is no need to update A ⁱ _o , U ⁱ _o , C ⁱ _o and T ⁱ _o , otherwise it is necessary to update the current initial mechanical calculation benchmark model A ⁱ _o and the current initial cable structure The support angular coordinate vector U ⁱ _o , the current initial cable structure steady-state temperature data vector T ⁱ _o and the current initial value vector C ⁱ _o of the monitored quantity are updated, while the current initial damage vector d ⁱ _o of the evaluated object remains unchanged. The updating method is carried out according to the steps specified in the technical scheme and claims.

Step 8: On the basis of the current initial mechanical calculation benchmark model A ⁱ _o , perform several mechanical calculations according to the steps specified in the technical proposal and the claims, and establish the numerical change matrix ΔC ⁱ and the monitored quantity of unit damage through calculation. Evaluation object unit change vector D ⁱ _u , where, if the evaluated object is a supporting cable in the cable system, then it is assumed that the supporting cable has damage on the basis of the existing damage of the supporting cable represented by the vector d ⁱ _o Unit damage (for example, take 5%, 10%, 20% or 30% damage as unit damage), if the object to be evaluated is a load, it is assumed that the load has changed by the amount represented by the vector d ⁱ _o Add load unit change on the basis (if the load is a distributed load, and the distributed load is a line distributed load, the load unit change can be 1kN/m, 2kN/m, 3kN/m or 1kNm/m, 2kNm/m, 3kNm /m etc. as the unit change; if the load is a distributed load, and the distributed load is a surface distributed load, the load unit change can be 1MPa, 2MPa, 3MPa or 1kNm/m ² , 2kNm/m ² , 3kNm/m ² , etc. If the load is a concentrated load, and the concentrated load is a force couple, the load unit change can be changed in units of 1kNm, 2kNm, 3kNm, etc.; if the load is a concentrated load, and the concentrated load is a concentrated force, the load unit The change can be changed in units of 1kN, 2kN, 3kN, etc.; if the load is a body load, the change in the load unit can be changed in units of 1kN/m ³ , 2kN/m ³ , 3kN/m ³ , etc.).

Step 9: Establish linear relationship error vector e ⁱ and vector g ⁱ . Using the previous data ("the current initial value vector C ⁱ _o of the monitored quantity", "the numerical change matrix of the monitored quantity per unit damage ΔC ⁱ "), each calculation is performed in the eighth step, that is, each calculation assumes that When only one of the assessed objects has increased unit damage or load unit change, when it is assumed that the kth (k=1,2,3,...,N) assessed object has increased unit damage or load unit change, Each calculation constitutes a damage vector, which is represented by d ⁱ _tk , and the current vector of the corresponding monitored quantity calculation is C ⁱ _tk (see step 8), and the number of elements of the damage vector d ⁱ _tk is equal to that of the evaluated object Quantity, the value of only one element among all the elements of vector d ⁱ _tk is the unit damage or load unit change value of the evaluated object assuming that the unit damage or load unit change is assumed to increase in each calculation, and the values of other elements of d ⁱ _tk are taken as 0, the number of the element that is not 0 is the same as the corresponding relationship between the number of the element that is not 0 and the evaluated object that is assumed to increase the damage of the unit or the change of the load unit, and the corresponding relationship between the elements with the same number of other vectors and the evaluated object; d ⁱ _tk The element numbering rule is the same as the element numbering rule of the initial damage vector d _o of the evaluated object, and the elements of d ⁱ _tk are in one-to-one correspondence with the elements of d _o . Put C ⁱ _tk , C ⁱ _o , ΔC ⁱ , d ⁱ _tk into formula (1), and obtain a linear relationship error vector e ⁱ _k , and each calculation obtains a linear relationship error vector e ⁱ _k ; the next step of e ⁱ _k The mark k indicates that the kth (k=1,2,3,...,N) evaluated object increases unit damage or load unit change. If there are N evaluated objects, there will be N calculations, and there will be N linear relationship error vectors e ⁱ _k , and the N linear relationship error vectors e ⁱ _k will be added to obtain a vector, and each element of this vector will be divided by The new vector obtained after N is the final linear relationship error vector e ⁱ . The vector g ⁱ is equal to the final error vector e ⁱ . Save the vector g ⁱ on the computer hard disk running the health monitoring system software for use by the health monitoring system software.

Step 10: Define the current nominal damage vector d ⁱ _c and the current actual damage vector d ⁱ , the number of elements of d ⁱ _c and d ⁱ is equal to the number of evaluated objects, and the number of elements of d ⁱ _c and d ⁱ is equal to the number of evaluated objects There is a one-to-one correspondence between d ⁱ _c and d ⁱ , the element values of d i c and d i represent the damage degree or load change degree of the corresponding evaluated object, d ⁱ _c and d ⁱ are the same as the element numbering rules of the initial damage vector d _o of the evaluated object, The elements of d ⁱ _c , the elements of d ⁱ and the elements of d _o are in one-to-one correspondence.

Step 11: According to the current numerical vector C ⁱ of the monitored quantity, the "current initial numerical vector C ⁱ _o of the monitored quantity", "the numerical change matrix of the monitored quantity with unit damage ΔC ⁱ ", and "the current nominal damage vector d ⁱ _c " The approximate linear relationship exists between , the approximate linear relationship can be expressed as formula (2), and the non-inferior solution of the current nominal damage vector d ⁱ _c is calculated according to the multi-objective optimization algorithm, that is, there is a reasonable error, but it can be obtained from A solution that determines the location of damaged cables and their nominal damage levels in all cables.

The current nominal damage vector d ⁱ _c can be obtained by solving Equation (2) by using the Goal Attainment Method in the multi-objective optimization algorithm.

Step 12: Calculate each element of the current actual damage vector d ⁱ according to the definition of the current actual damage vector d ⁱ of the cable system and the definition of its elements, so that the health status of the evaluated object can be determined by d ⁱ . The k-th element d ⁱ _k of the current actual damage vector d ⁱ represents the current actual health status of the k-th evaluated object in the i-th cycle.

d ⁱ _k represents the current actual health status of the kth evaluated object in the ith cycle, if the evaluated object is a supporting cable in the cable system, then d ⁱ _k represents its current actual damage, d ⁱ _k is When 0 means no damage, when it is 100%, it means that the supporting cable completely loses its bearing capacity, and when it is between 0 and 100%, it means that it loses the corresponding proportion of bearing capacity. Therefore, according to the current actual damage vector d ⁱ of the evaluated object, the core The health status of the subject being assessed.

Step 13: The computer in the health monitoring system generates reports on the health status of the cable system automatically or by personnel operating the health monitoring system on a regular basis.

Step 14: Under the specified conditions, the computer in the health monitoring system automatically operates the communication alarm equipment to alarm the monitoring personnel, the owner and (or) the designated personnel.

Step 15: Establish the identification vector B ⁱ , if the elements of the identification vector B ⁱ are all 0, go back to the sixth step to continue the health monitoring and calculation of the cable system; if the elements of the identification vector B ⁱ are not all 0, After completing the subsequent steps, enter the next cycle.

Step 16: Calculate each element d ⁱ +1 o of the initial damage vector d ⁱ⁺¹ _o required for the next (i+ _1th , i=1,2,3,4,…) cycle (k=1, 2, 3,..., N); on the basis of the initial mechanical calculation benchmark model A _o , the support angular displacement constraint is first imposed on the cable structure support in A _o , and the angular displacement constraint of the support The value is obtained from the value of the corresponding element in the support angular displacement vector V, and then the temperature change is applied to the cable structure in A _o , and the value of the temperature change is obtained from the steady-state temperature change vector S, and then the health status of the cable is After being d ⁱ⁺¹ _o , what is obtained is the mechanical calculation benchmark model A ⁱ⁺¹ required for the next cycle, that is, the i+1th (i=1,2,3,4,...) cycle; i+1 times, i=1, 2, 3, 4,...) The current initial cable structure steady-state temperature data vector T ⁱ⁺¹ _o required for the cycle is equal to T ⁱ _o , the next time (i.e. the i+1th time, The angular coordinate vector U ⁱ⁺¹ _o of the current initial cable structure support required by i=1, 2, 3, 4, ...) cycle is equal to U ⁱ _o . After obtaining A ⁱ⁺¹ , d ⁱ⁺¹ _o , U ⁱ⁺¹ _o and T ⁱ⁺¹ _o , the current specific values of all the monitored quantities in A ⁱ⁺¹ are obtained through mechanical calculations, and these specific values are composed of the following The current initial value vector C ⁱ⁺¹ _o of the monitored quantity required for one cycle, that is, the i+1th cycle.

Step 17: Go back to Step 6 and start the cycle from Step 6 to Step 17.

Claims (1)

1. Simplified angular displacement spatial coordinate monitoring damaged cable load progressive identification method, characterized in that said method comprises: a. When the load borne by the cable structure changes, but the load the cable structure is bearing does not exceed the initial allowable load of the cable structure, this method is applicable; the initial allowable load of the cable structure refers to the allowable load of the cable structure at the time of completion, It can be obtained through conventional mechanical calculations; this method collectively refers to the evaluated supporting cables and loads as "assessed objects", and the sum of the number of evaluated supporting cables and the number of loads is N, which is the number of "assessed objects" is N; this method uses the name "core assessed object" to specifically refer to the assessed support cables in the "assessed object", and this method uses the name "secondary assessed object" to specifically refer to the assessed support cable in the "assessed object". load; determine the numbering rule of the evaluated object, according to this rule, number all the evaluated objects in the cable structure, and the number will be used to generate vectors and matrices in subsequent steps; this method uses the variable k to represent this number, k =1,2,3,…,N; Suppose there are M ₁ supporting cables in the cable system, obviously the number of the core evaluated objects is M ₁ ; determine the measured points of the designated space coordinates to be monitored, and give all designated points Numbering; the space coordinate components to be monitored of each measurement point have been determined, and all measured space coordinate components are numbered; the above numbers will be used to generate vectors and matrices in subsequent steps; "all the monitored space coordinates of the cable structure Data" is composed of all the above-mentioned measured spatial coordinate components; for the sake of convenience, in this method, the "monitored spatial coordinate data of the cable structure" is referred to as "monitored quantity"; the sum of all monitored quantities is recorded as M, M is greater than the number of core evaluated objects, and M is smaller than the number of evaluated objects; in this method, the time interval between any two measurements of real-time monitoring of the same quantity shall not be greater than 30 minutes, and the moment of measuring and recording data is called Actual data recording time; the external force borne by objects and structures can be called load, and load includes surface load and body load; surface load, also known as surface load, is a load acting on the surface of an object, including concentrated load and distributed load; body load It is the load continuously distributed at each point inside the object, including the self-weight and inertial force of the object; the concentrated load is divided into two types: concentrated force and concentrated force couple. In the coordinate system including the Cartesian coordinate system, a concentrated force It can be decomposed into three components. Similarly, a concentrated force couple can also be decomposed into three components. If the load is actually a concentrated load, a concentrated force component or a concentrated force couple component is counted or counted as a load in this method , the change of the load at this time is embodied as the change of a concentrated force component or a concentrated force couple component; distributed load is divided into line distributed load and surface distributed load, and the description of distributed load includes at least the action area of distributed load and the size of distributed load, The size of the distributed load is expressed by the distribution concentration, and the distribution concentration is expressed by the distribution characteristics and amplitude; if the load is actually a distributed load, when this method talks about the change of the load, it actually refers to the amplitude of the distribution concentration of the distributed load. The value changes, while the distribution characteristics of the action area and distribution intensity of all distributed loads remain unchanged; in a coordinate system including Cartesian coordinate system, a The distributed load can be decomposed into three components. If the magnitudes of the respective distribution concentration of the three components of the distributed load change, and the ratios of the changes are not all the same, then in this method, the three components of the distributed load It is counted or counted as three distributed loads. At this time, one load represents a component of the distributed load; the body load is the load continuously distributed at each point inside the object, and the description of the body load includes at least the action area of the body load and the area of the body load The size of the body load is expressed by the distribution concentration, and the distribution concentration is expressed by the distribution characteristics and amplitude; if the load is actually a body load, what is actually dealt with in this method is the magnitude of the distribution concentration of the body load change, while the distribution characteristics of the action area and distribution concentration of all body loads remain unchanged. At this time, when the load change is mentioned in this method, it actually refers to the change of the magnitude of the distribution concentration of the body load. When , the loads that change refer to those body loads whose magnitude of distribution concentration changes; in a coordinate system including Cartesian coordinate system, a body load can be decomposed into three components, if the body load If the amplitudes of the respective distribution concentration of the three components change, and the ratios of the changes are not all the same, then in this method, the three components of the body load are counted or counted as three distributed loads; b. This method defines "the temperature measurement and calculation method of the cable structure of this method" according to steps b1 to b3; b1: Query or measure the temperature-dependent heat transfer parameters of the composition materials of the cable structure and the environment where the cable structure is located, use the design drawings, as-built drawings of the cable structure, and the geometrically measured data of the cable structure, and use these data and parameters to establish a cable structure. The heat transfer calculation model of the structure; query the meteorological data of not less than 2 years in recent years where the cable structure is located, and count the number of cloudy days during this period as T cloudy days. In this method, the number of cloudy days that cannot be seen during the day The whole day of the sun is called a cloudy day, and the highest and lowest temperature between 0:00 and 30 minutes after the sunrise time of the next day on each of the T cloudy days is counted. The meteorological sunrise time determined by the sun and the revolution law does not mean that the sun must be visible on that day, and the required sunrise time of each day can be obtained by querying the data or through conventional meteorological calculations. Every cloudy day from 0 o'clock to The maximum temperature difference between the highest temperature and the lowest temperature within 30 minutes after sunrise of the next day is called the maximum temperature difference of the daily temperature of the cloudy day. If there are T cloudy days, there will be the maximum temperature difference of the daily temperature of T cloudy days. Take T The maximum value of the maximum temperature difference of daily air temperature in a cloudy day is the reference daily temperature difference, which is recorded as ΔT _r ; query the location of the cable structure and the altitude interval of not less than 2 years of meteorological data in recent years or obtain the cable structure from actual measurements The change data and change law of the temperature of the environment with time and altitude, and the maximum change rate ΔT of the temperature of the environment where the cable structure is located with respect to the altitude in recent years for the location of the cable structure and the altitude interval of not less than 2 years in recent years _h , for the convenience of description, the unit of ΔT _h is ℃/m; take "R cable structure surface points" on the surface of the cable structure, and the specific principle of taking "R cable structure surface points" is described in step b3, and later The temperature of the surface points of the R cable structures will be obtained through actual measurement, and the temperature data obtained from the actual measurement is called "the measured data of the surface temperature of the R cable structures". The temperature of the surface points of the R cable structures is called the calculated temperature data as "calculation data of the surface temperature of the R cable structures"; For less than three different altitudes, at each selected altitude, at least two points are selected at the intersection of the horizontal plane and the surface of the cable structure, and the outer normal of the surface of the structure is indexed from the selected point, all selected The outer normal direction is called "the direction of measuring the temperature distribution of the cable structure along the wall thickness". The direction of temperature distribution along the wall thickness must include the outer normal direction of the sunny surface of the cable structure and the outer normal direction of the shaded surface of the cable structure, and the temperature distribution along the wall thickness of each measurement cable structure is uniform in the cable structure. Select no less than three points, for the support cable along the direction of each measuring cable structure temperature distribution along the wall thickness, only take one point, only measure the temperature of the surface point of the support cable, measure the temperature of all selected points, measure The obtained temperature is called "the temperature distribution data of the cable structure along the thickness", Among them, the "temperature distribution data of the cable structure along the thickness" measured along the same "intersection line between the horizontal plane and the surface of the cable structure" and "the direction of measuring the temperature distribution of the cable structure along the wall thickness" is called in this method "The temperature distribution data of the cable structure along the thickness at the same altitude", assume that H different altitudes are selected, and at each altitude, B are selected to measure the temperature distribution direction of the cable structure along the wall thickness, along each To measure the temperature distribution direction of the cable structure along the wall thickness, E points are selected in the cable structure, where H and E are not less than 3, and B is not less than 2. For the supporting cable, E is equal to 1. On the cable structure, "measurement cable structure The total number of "points of temperature distribution data along the thickness" is HBE, and the temperature of these HBE "points of temperature distribution data along the thickness of the cable structure" will be obtained through actual measurement later, and the temperature data obtained by actual measurement are called "HBE cable The measured data of the temperature along the thickness of the structure”, if the heat transfer calculation model of the cable structure is used to calculate the temperature of the HBE points that measure the temperature distribution data of the cable structure along the thickness, the calculated temperature data is called "HBE cable structure temperature calculation data along the thickness"; select a location at the location of the cable structure according to the meteorological temperature measurement requirements, and the temperature of the environment where the cable structure is located that meets the meteorological temperature measurement requirements will be measured at this location; at the location of the cable structure Choose a location in an open and unsheltered place, which should be able to get the fullest sunshine of the day every day of the year, and place a carbon steel plate at this location, called the reference The reference plate should not be in contact with the ground. The distance between the reference plate and the ground should not be less than 1.5 meters. One side of the reference plate faces the sun, called the sunny side. The sunny side of the reference plate is rough and dark. On every day of the year, the most sufficient sunshine of the day that a flat panel can get in this place can be obtained, and the non-sun-facing side of the reference flat-panel is covered with thermal insulation material, and the temperature of the sunny side of the reference flat-panel will be obtained through real-time monitoring; b2: Obtain the measured surface temperature data of the R cable structures at the surface points of the above R cable structures through real-time monitoring, and at the same time obtain the temperature distribution data of the previously defined cable structures along the thickness through real-time monitoring. The temperature data of the environment where the structure is located; through real-time monitoring, the temperature measured data series of the environment where the cable structure is located is obtained from the sunrise time of the day to 30 minutes after the sunrise time of the next day. The measured temperature data of the environment where the cable structure is located between the time and 30 minutes after sunrise of the next day are arranged in chronological order, and the highest temperature and the lowest temperature in the air temperature measurement data sequence of the environment where the cable structure is located are found. The maximum temperature difference in the air temperature measured data sequence minus the minimum temperature is the maximum temperature difference between the sunrise time of the day and 30 minutes after the sunrise time of the next day in the environment where the cable structure is located, which is called the maximum temperature difference of the environment, and is recorded as ΔT _emax ; The temperature measured data sequence of the environment where the cable structure is located is obtained through conventional mathematical calculations. The measured data series of the temperature of the sunny side of the reference plate between 30 minutes, the measured data series of the temperature of the sunny side of the reference plate from the sunrise time of the current day to the sunny side of the reference plate 30 minutes after the sunrise time of the next day The measured data of the temperature of the reference plate are arranged in chronological order, find the highest temperature and the lowest temperature in the measured data sequence of the temperature of the sunny side of the reference plate, and subtract the lowest temperature from the highest temperature in the measured data sequence of the temperature of the sunny side of the reference plate Temperature obtains the maximum temperature difference between the sunrise time of the day and 30 minutes after the sunrise time of the next day from the temperature of the sunny side of the reference plate, which is called the maximum temperature difference of the reference plate, and is recorded as ΔT _pmax ; The measured data series of cable structure surface temperature of all R cable structure surface points between 30 minutes after the sunrise time of the next day, there are R cable structure surface temperature measured data sequences of R cable structure surface points, each cable structure The measured data sequence of the surface temperature is arranged in chronological order by the measured data of the surface temperature of the cable structure between the sunrise time of the day and 30 minutes after the sunrise time of the next day at a surface point of the cable structure, and the measured data sequence of the surface temperature of each cable structure is found From the highest temperature and the lowest temperature in the data series, subtract the lowest temperature from the highest temperature in the measured data series of the surface temperature of each cable structure to obtain the temperature of each cable structure surface point from the sunrise time of the day to 30 minutes after the sunrise time of the next day If there are R surface points of the cable structure, there are R maximum temperature difference values between the sunrise time of the day and 30 minutes after the sunrise time of the next day, and the maximum value is called the maximum temperature difference of the cable structure surface, which is denoted as ΔT _smax ; From the measured data sequence of the surface temperature of each cable structure, the rate of change of the temperature of each cable structure surface point with respect to time is obtained through conventional mathematical calculations, and the temperature of each cable structure surface point with respect to time The rate of change also changes with time; after obtaining HBE "temperature distribution data along the thickness of the cable structure" at the same time between the sunrise time of the day and 30 minutes after the sunrise time of the next day through real-time monitoring, calculate the The difference between the maximum temperature and the minimum temperature in a total of BE "temperature distribution data of the cable structure along the thickness at the same altitude" at a selected altitude, the absolute value of this difference is called "thickness direction of the cable structure at the same altitude". If H different altitudes are selected, there will be H "maximum temperature differences in the thickness direction of the cable structure at the same altitude", and the maximum value of the H "maximum temperature differences in the thickness direction of the cable structure at the same altitude" is "The maximum temperature difference in the thickness direction of the cable structure", denoted as ΔT _tmax ; b3: Measurement and calculation to obtain the steady-state temperature data of the cable structure; firstly, determine the moment to obtain the steady-state temperature data of the cable The time of the structural steady-state temperature data is between the sunset time of the current day and 30 minutes after the sunrise time of the next day. The sunset time refers to the meteorological sunset time determined according to the laws of the earth's rotation and revolution. The data can be queried or through conventional weather The required sunset time of each day can be obtained through scientific calculation; the second condition a condition is that during the period between the sunrise time of the current day and 30 minutes after the sunrise time of the next day, the maximum temperature difference ΔT _pmax and the maximum temperature difference of the reference plate The maximum temperature difference ΔT _smax on the surface of the cable structure is not greater than 5 degrees Celsius; the b condition of the second condition is that during the period between the sunrise of the day and 30 minutes after the sunrise of the next day, in the environment obtained by the previous measurement and calculation The maximum temperature difference ΔT _emax is not greater than the reference daily temperature difference ΔT _r , and the maximum temperature difference ΔT _pmax of the reference plate minus 2 degrees Celsius is not greater than ΔT _emax , and the maximum temperature difference ΔT _smax on the surface of the cable structure is not greater than ΔT _pmax ; only the second item a One of the condition and b condition is said to meet the second condition; the third condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the absolute value of the temperature change rate of the environment where the cable structure is located with respect to time is not greater than each 0.1 degrees Celsius per hour; the fourth condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the absolute value of the temperature change rate of each cable structure surface point in the R cable structure surface points with respect to time is not greater than 0.1 degrees Celsius per hour The fifth condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the measured data of the cable structure surface temperature of each cable structure surface point in the R cable structure surface points is from the sunrise time of the day to the day after the sunrise time of the next day The minimum value between 30 minutes; the sixth condition is that at the moment when the steady-state temperature data of the cable structure is obtained, the "maximum temperature difference in the thickness direction of the cable structure" ΔT _tmax is not greater than 1 degree Celsius; this method utilizes the above six conditions, and the following Any one of the three kinds of time is called "mathematical time for obtaining the steady-state temperature data of the cable structure". Item 1 to item 5 conditions, the second type of time is the time that only meets the sixth condition in the above "conditions related to the time to determine the time to obtain the steady-state temperature data of the cable structure", and the third type of time is when the above-mentioned conditions are met at the same time The moment of the first item to the sixth condition in "Conditions related to the moment of determining the time to obtain the steady-state temperature data of the cable structure"; At one moment, the moment of obtaining the steady-state temperature data of the cable structure is the mathematical moment of obtaining the steady-state temperature data of the cable structure; if the mathematical moment of obtaining the steady-state temperature data of the cable structure is not any moment in the actual recording data moment in this method, Then take this method closest to the mathematical time of obtaining the steady-state temperature data of the cable structure The actual recorded data moment is the moment when the steady-state temperature data of the cable structure is obtained; this method will use the measured and recorded quantity at the moment when the steady-state temperature data of the cable structure is obtained to perform cable structure-related health monitoring analysis; this method approximately considers that the obtained The temperature field of the cable structure at the moment of the steady-state temperature data of the cable structure is in a steady state, that is, the temperature of the cable structure at this moment does not change with time, and this moment is the "moment of obtaining the steady-state temperature data of the cable structure" of this method; Heat transfer characteristics of the structure, using the “measured surface temperature data of R cable structures” and “measured temperature data of HBE cable structures along the thickness” at the moment when the steady-state temperature data of the cable structure is obtained, and using the heat transfer calculation model of the cable structure, through The temperature distribution of the cable structure at the moment of obtaining the steady-state temperature data of the cable structure is obtained by conventional heat transfer calculation. At this time, the temperature field of the cable structure is calculated according to the steady state. The temperature distribution data of the structure includes the calculated temperature of the R cable structure surface points on the cable structure, and the calculated temperature of the R cable structure surface points is called the R cable structure steady-state surface temperature calculation data, and also includes the previously selected cable structure The calculated temperature of the HBE "points for measuring the temperature distribution data of the cable structure along the thickness", and the calculated temperature of the HBE "points for measuring the temperature distribution data of the cable structure along the thickness" are called "calculated data of the temperature of the HBE cable structure along the thickness" , when the measured surface temperature data of the R cable structures is equal to the calculated data of the steady-state surface temperature of the R cable structures, and the "measured data of the temperature along the thickness of the HBE cable structures" corresponds to the "calculated data of the temperature along the thickness of the HBE cable structures". When they are equal, the calculated temperature distribution data of the cable structure at the moment when the cable structure steady-state temperature data is obtained is called "cable structure steady-state temperature data" in this method, and the "R cable structure surface temperature measured data " is called "the measured data of the steady-state surface temperature of R cable structures", and "the measured data of the temperature of the HBE cable structures along the thickness" is called "the measured data of the steady-state temperature of the HBE cable structures along the thickness"; When "R cable structure surface points", the number and distribution of "R cable structure surface points" must meet three conditions. The first condition is that when the cable structure temperature field is in a steady state, when any point on the cable structure surface When the temperature of is obtained by the linear interpolation of the measured temperature of the point adjacent to the arbitrary point on the surface of the cable structure among the "R cable structure surface points", the temperature of the arbitrary point on the surface of the cable structure obtained by linear interpolation is the same as that of the surface of the cable structure The error of the actual temperature at this arbitrary point is not greater than 5%; the cable structure surface includes the supporting cable surface; the second condition is that the number of points at the same altitude in the "R cable structure surface points" is not less than 4, and " The points at the same altitude in the "R cable structure surface points" are uniformly distributed along the cable structure surface; The maximum value Δh among the values is not greater than the value obtained by dividing ΔT _h by 0.2°C. For the convenience of description, the unit of ΔT _h is ℃/m, and for the convenience of description, the unit of Δh is m;" The definition of two adjacent cable structure surface points along the altitude of "R cable structure surface points" means that when only the altitude is considered, there is no cable structure surface point in the "R cable structure surface points". The altitude value of the surface point is between the altitude values of two adjacent cable structure surface points; the third condition is to query or calculate according to meteorological routines to obtain the sunshine law of the cable structure location and the altitude interval, and then according to the cable structure According to the geometric characteristics and orientation data of the structure, find the positions of those surface points on the cable structure that receive the most sunshine time throughout the year, and at least one cable structure surface point in the "R cable structure surface points" is on the cable structure that is exposed to sunlight throughout the year. one of those surface points at which the hours of sunshine are greatest; c. According to the "temperature measurement and calculation method of the cable structure of this method", the steady-state temperature data of the cable structure in the initial state is directly measured and calculated, and the steady-state temperature data of the cable structure in the initial state is called the initial steady-state temperature data of the cable structure. It is recorded as "initial cable structure steady-state temperature data vector T _o "; the physical and mechanical performance parameters of various materials used in the cable structure _that vary with temperature are obtained from actual measurements or information; At the same moment when the steady-state temperature data vector T _o of the initial cable structure is obtained, the measured data of the initial cable structure is directly measured and calculated. The measured data of the initial cable structure includes the concentrated load measurement data of the cable structure, the distributed load measurement data of the cable structure, Cable structure body load measurement data, initial values of all monitored quantities, initial cable force data of all supporting cables, initial cable structure modal data, initial cable structure strain data, initial cable structure geometric data, initial cable structure support generalized coordinates The measured data including initial cable structure angle data and initial cable structure spatial coordinate data, the initial cable structure support generalized coordinate data include initial cable structure support spatial coordinate data and initial cable structure support angular coordinate data, after At the same time as the actual measurement data of the cable structure, the data that can express the health state of the support cable including the non-destructive testing data of the support cable are measured and calculated. At this time, the data that can express the health state of the support cable is called the initial health state of the support cable data; the initial values of all monitored quantities form the initial value vector C _o of the monitored quantity, and the numbering rule of the initial value vector C _o of the monitored quantity is the same as that of the M monitored quantities; Structural load measurement data establishes the initial damage vector d _o of the evaluated object, and the vector d _o represents the initial health state of the evaluated object of the cable structure represented by the initial mechanical calculation benchmark model A _o ; the elements of the initial damage vector d _o of the evaluated object The number is equal to N, the elements of d _o have a one-to-one correspondence with the evaluated object, and the numbering rules of the elements of the vector d _o are the same as the numbering rules of the evaluated object; if a certain element of d _o corresponds to the evaluated object is the index system A support cable in , then the value of this element of d _o represents the initial damage degree of the corresponding support cable. If the value of this element is 0, it means that the support cable corresponding to this element is intact and has no damage. If If the value is 100%, it means that the supporting cable corresponding to this element has completely lost its bearing capacity; if its value is between ₀ and 100%, it means that the supporting cable has lost its corresponding proportion of bearing capacity; The evaluated object corresponding to an element is a certain load. In this method, the value of the element of d _o is 0, which means that the initial value of the change of this load is 0; When the data of the healthy state of the structure, or it can be considered that the initial state of the structure is a state of no damage and no relaxation, the value of each element related to the supporting cable in the vector d _o is 0; the initial cable structure support angular coordinate data constitutes the initial cable knot Structural support angular coordinate vector U _o ; d. According to the design drawing of the cable structure, the as-built drawing and the actual measurement data of the initial cable structure, the initial health status data of the supporting cable, the measurement data of the concentrated load of the cable structure, the measurement data of the distributed load of the cable structure, the measurement data of the body load of the cable structure, and the data of the cable structure. The physical and mechanical performance parameters of the various materials used vary with temperature, the initial cable structure support angular coordinate vector U _o , the initial cable structure steady-state temperature data vector T _o and all the cable structure data obtained in the previous steps, to establish the calculation The initial mechanical calculation benchmark model A _o of the cable structure is entered into the "steady-state temperature data of the cable structure". The calculated data of the cable structure based on A _o must be very close to the measured data, and the difference between them shall not be greater than 5%; corresponding to A _o The "cable structure steady-state temperature data" is the "initial cable structure steady-state temperature data vector T _o "; the cable structure support angular coordinate data corresponding to A _o is the initial cable structure support angular coordinate vector U _o ; corresponding to A The health status of the evaluated object of _o is represented by the initial damage vector d _o of the evaluated object; the initial values of all monitored quantities corresponding to A _o are represented by the initial value vector C _o of the monitored quantities; U _o , T _o and d _o are The parameters of A _o , the initial values of all the monitored quantities obtained from the mechanical calculation results of A _o are the same as the initial values of all the monitored quantities represented by C _o , so it can also be said that C _o is composed of the mechanical calculation results of A _o , In this method, A _o , C _o , d _o , U _o and T _o are unchanged; e. In this method, except where the letter i clearly indicates the step number, the letter i only indicates the number of cycles, that is, the i-th cycle; the current initial value of the cable structure that needs to be established or has been established at the beginning of the i-th cycle The mechanical calculation benchmark model is recorded as the current initial mechanical calculation benchmark model A ⁱ _o , A _o and A ⁱ _o include temperature parameters, and the influence of temperature changes on the mechanical properties of the cable structure can be calculated; at the beginning of the i-th cycle, corresponding to A The "cable structure steady-state temperature data" of ⁱ _o is represented by the current initial cable structure steady-state temperature data vector T ⁱ _o , the definition of vector T ⁱ _o is the same as that of vector T _o , and the elements of T ⁱ _o are the same as T _o The elements of are in one-to-one correspondence; at the beginning of the i-th cycle, the "cable structure support angular coordinate data" corresponding to A ⁱ _o is represented by the current initial cable structure support angular coordinate vector U ⁱ _o , and the definition method of vector U ⁱ _o In the same way as the definition of the vector U _o , the elements of U ⁱ _o correspond to the elements of U _o one by one; the current initial damage vector of the evaluated object required at the beginning of the i-th cycle is recorded as d ⁱ _o , and d ⁱ _o represents the At the beginning of the cycle, the health status of the evaluated object of the search structure A ⁱ _o is defined. The definition of d ⁱ _o is the same as that of d _o , and the elements of d ⁱ _o correspond to the elements of d _o one by one; when the i-th cycle starts , the initial values of all the monitored quantities are represented by the current initial value vector C ⁱ _o of the monitored quantity. The definition method of the vector C ⁱ _o is the same as that of the vector C _o , and the elements of C ⁱ _o are one by one with the elements of C _o Correspondingly, the current initial value vector C ⁱ _o of the monitored quantity represents the specific values of all the monitored quantities corresponding to A ⁱ _o ; U ⁱ _o , T ⁱ _o and d ⁱ _o are the characteristic parameters of A ⁱ _o , and C ⁱ _o is determined by A ⁱ _o is composed of mechanical calculation results; at the beginning of the first cycle, A ⁱ _o is recorded as A ¹ _o , and the method of establishing A ¹ _o is to make A ¹ _o equal to A _o ; at the beginning of the first cycle, T ⁱ _o Denote it as T ¹ _o , the method of establishing T ¹ _o is to make T ¹ _o equal to T _o ; at the beginning of the first cycle, U ⁱ _o is recorded as U ¹ _o , and the method of establishing U ¹ _o is to make U ¹ _o equal to U _o ; at the beginning of the first cycle, d ⁱ _o is recorded as d ¹ _o , and the method of establishing d ¹ _o is to make d ¹ _o equal to d _o ; at the beginning of the first cycle, C ⁱ _o is recorded as C ¹ _o , and the establishment The method of C ¹ _o is to make C ¹ _o equal to C _o ; f. From here, enter the cycle from step f to step q; during the service process of the structure, according to "the temperature measurement and calculation method of the cable structure of this method", the current data of the steady-state temperature data of the cable structure are continuously measured and calculated, and all The current data of "cable structure steady-state temperature data" constitutes the current cable structure steady-state temperature data vector T ⁱ , the definition method of vector T ⁱ is the same as that of vector T _o , and the elements of T ⁱ correspond to the elements of T _o one by one ; At the same moment when the current steady-state temperature data vector T ⁱ of the cable structure is obtained from the actual measurement, the current data of the angular coordinates of the cable structure supports are obtained from the actual measurement, and all the current data of the angular coordinates of the cable structure supports form the vector U ⁱ , the vector U ⁱ is defined in the same way as the vector U _o ; when the vector T ⁱ is obtained from the actual measurement, all the cable structures in the cable structure at the same time when the current cable structure steady-state temperature data vector T ⁱ is obtained The current value of the monitored quantity. All these values form the current value vector C ⁱ of the monitored quantity. The definition method of the vector C ⁱ is the same as that of the vector C _o . The elements of C ⁱ correspond to the elements of C _o one by one, indicating that the same The value of the monitored quantity at different times; g. According to the measured support angle coordinate vector U ⁱ of the current cable structure and the current steady-state temperature data vector T ⁱ of the cable structure, follow steps g1 to g3 to update the current initial mechanical calculation benchmark model A ⁱ _o and the current initial value vector C of the monitored quantity ⁱ _o , the current initial cable structure steady-state temperature data vector T ⁱ _o and the current initial cable structure support angular coordinate vector U ⁱ _o , while the current initial damage vector d ⁱ _o of the evaluated object remains unchanged; g1. Compare T ⁱ and T ⁱ _o , U ⁱ and U ⁱ _o respectively, if T ⁱ is equal to T ⁱ _o and U ⁱ is equal to U ⁱ _o , there is no need to compare A ⁱ _o , U ⁱ _o , C ⁱ _o and T ⁱ _o is updated, otherwise A ⁱ _o , U ⁱ _o , C ⁱ _o and T ⁱ _o need to be updated according to the following steps; g2. Calculate the difference between U ⁱ and U _o . The difference between U ⁱ and U _o is the support angular displacement of the cable structure support with respect to the initial position. Use the support angular displacement vector V to represent the support angular displacement, and V is equal to U ⁱ minus Remove U _o ; calculate the difference between T ⁱ and T _o , the difference between T ⁱ and T _o is the change of the current cable structure steady-state temperature data with respect to the initial cable structure steady-state temperature data, the difference between T ⁱ and T _o is the steady-state temperature The change vector S indicates that S is equal to T ⁱ minus T _o , and S indicates the change of the steady-state temperature data of the cable structure; g3. First apply the support angular displacement constraint to the support of the cable structure in A _o , the value of the support angular displacement constraint is taken from the value of the corresponding element in the support angular displacement vector V, and then impose a constraint on the cable structure in A _o The temperature change, the value of the applied temperature change is taken from the steady-state temperature change vector S, and the current initial mechanical calculation benchmark model is updated after applying the support angular displacement constraint to the cable structure support in A _o and applying the temperature change to the cable structure A ⁱ _o , while updating A ⁱ _o , all element values of U ⁱ _o are also replaced by corresponding values of all elements of U ⁱ , that is, U ⁱ _o is updated, and all element values of T ⁱ _o are also replaced by corresponding values of all elements of T ⁱ , that is, T ⁱ _o is updated, so that U ⁱ _o and T ⁱ _o corresponding to A ⁱ _o are obtained correctly, and d ⁱ _o remains unchanged at this time; when A ⁱ _o is updated, the index of A ⁱ _o The health status is represented by the current initial damage vector d ⁱ _o of the evaluated object, the steady-state temperature of the cable structure of A ⁱ _o is represented by the current data vector T ⁱ _o of the steady-state temperature of the cable structure, and the support angle coordinates of A ⁱ _o are represented by the current initial cable The structural support angular coordinate vector U ⁱ _o represents; the method of updating C ⁱ _o is: after updating A ⁱ _o , obtain the current specific values of all monitored quantities in A ⁱ _o through mechanical calculations, and these specific values form C ⁱ _o ; h. On the basis of the current initial mechanical calculation benchmark model A ⁱ _o , perform several mechanical calculations according to steps h1 to h4, and establish the numerical change matrix ΔC ⁱ of the monitored quantity of damage per unit and the unit change vector D ⁱ of the evaluated object through calculation _u ; h1. At the beginning of the ith cycle, directly obtain ΔC ⁱ and D ⁱ _u according to the methods listed in step h2 to step h4; at other times, after updating A ⁱ _o in step g, you must follow steps h2 to h4 The method listed in step h4 regains ΔC ⁱ and D ⁱ _u , if A ⁱ _o is not updated in step g, then directly transfer to step i for follow-up work here; h2. Carry out several mechanical calculations on the basis of the current initial mechanical calculation benchmark model A ⁱ _o . The number of calculations is numerically equal to the number N of all evaluated objects. There are N evaluation objects and there are N calculations; Numbering rules, calculations are performed sequentially; each calculation assumes that there is only one evaluated object, and the unit damage or load unit change is added on the basis of the original damage or load. Specifically, if the evaluated object is a supporting cable in the cable system , then it is assumed that the support cable will increase the unit damage, if the evaluated object is a load, it is assumed that the load will increase the load unit change, and record the increased unit damage or load unit change with D ⁱ _uk , where k represents Increment the number of the assessed object for unit damage or load unit change, D ⁱ _uk is an element of the assessed object unit change vector D ⁱ _u , the numbering rule of the elements of the assessed object unit change vector D ⁱ _u is the same as that of the vector d _o The numbering rules of the elements are the same; the evaluated object with additional unit damage or load unit change in each calculation is different from the evaluated object with additional unit damage or load unit change in other calculations, and each calculation uses the mechanical method to calculate the index The current calculated values of all the monitored quantities of the structure, the current calculated values of all the monitored quantities obtained by each calculation form a current vector of the monitored quantities calculation; when it is assumed that the kth assessed object is added with unit damage or load unit change , use C ⁱ _tk to represent the corresponding "monitored quantity calculation current vector"; when numbering the elements of each vector in this step, the same numbering rule should be used with other vectors in this method to ensure that the elements in each vector in this step Any element, with the elements of the same number in other vectors, expresses the relevant information of the same monitored quantity or the same object; the definition of C ⁱ _tk is the same as that of the vector C _o , and the elements of C ⁱ _tk are the same as C The elements of _o correspond one-to-one; h3. The vector C ⁱ _tk obtained by each calculation is subtracted from the vector C ⁱ _o to obtain a vector, and then each element of the vector is divided by the value of unit damage or load unit change assumed in this calculation to obtain a "being The numerical change vector of the monitored quantity δC ⁱ _k "; if there are N evaluated objects, there are N "numerical change vectors of the monitored quantity"; h4. From these N "value change vectors of monitored quantities" according to the numbering rules of N evaluated objects, a "monitored quantity numerical change matrix ΔC ⁱ " with N columns is formed in turn; the numerical value of monitored quantities per unit damage Each column of the change matrix ΔC ⁱ corresponds to a unit change vector of the monitored quantity; each row of the value change matrix ΔC ⁱ of the unit damage monitored quantity corresponds to the same monitored quantity when the unit damage or the load unit changes when different evaluated objects different unit change ranges; the numbering rules of the columns of the unit damage monitored quantity numerical change matrix ΔC ⁱ are the same as the numbering rules of the elements of the vector d _o , and the numbering rules of the rows of the unit damage monitored quantity numerical change matrix ΔC ⁱ are the same as M The numbering rules of the monitored quantities are the same; i. Define the current nominal damage vector d ⁱ _c and the current actual damage vector d ⁱ , the number of elements of d ⁱ _c and d ⁱ is equal to the number of evaluated objects, and the distance between the elements of d ⁱ _c and d ⁱ and the evaluated object is One-to-one correspondence, the element value of d ⁱ _c represents the nominal damage degree or nominal load variation of the corresponding evaluated object, d ⁱ _c and d ⁱ are the same as the element numbering rules of the initial damage vector d _o of the evaluated object, d ⁱ _c The elements of , the elements of d ⁱ and the elements of d _o are in one-to-one correspondence; j. According to the relationship between the current numerical vector C ⁱ of the monitored quantity and the "current initial numerical vector C ⁱ _o of the monitored quantity", "the numerical change matrix of the monitored quantity with unit damage ΔC ⁱ ", and "the current nominal damage vector d ⁱ _c " Approximate linear relationship, the approximate linear relationship can be expressed as formula 1. In formula 1, other quantities except d ⁱ _c are known, and the current nominal damage vector d ⁱ _c can be calculated by solving formula 1; Formula 1 k. The kth element d ⁱ _k of the current actual damage vector d ⁱ expressed by formula 2 is the same as the kth element d i ok of the current initial damage vector d ⁱ _o of the evaluated object and the kth element d ⁱ _ok of the current nominal damage vector d ⁱ _c The relationship among k elements d ⁱ _ck is calculated to obtain all the elements of the current actual damage vector d ⁱ ; In formula 2, k=1,2,3,...,N; d ⁱ _k represents the current actual health status of the kth evaluated object in the i-th cycle, if the evaluated object is a support in the cable system Then d ⁱ _k represents its current actual damage. When d ⁱ _k is 0, it means no damage. When it is 100%, it means that the supporting cable completely loses its bearing capacity. When it is between 0 and 100%, it means that it loses the corresponding proportion of bearing capacity. Ability, so far this method realizes the identification of the health status of the core evaluated object; l. After obtaining the current nominal damage vector d ⁱ _c , establish the identification vector B ⁱ according to formula 3, and formula 4 gives the definition of the kth element of the identification vector B ⁱ ; Formula 3 In formula 4, the element B ⁱ _k is the kth element of the identification vector B ⁱ , D ⁱ _uk is the kth element of the unit change vector D ⁱ _u of the evaluated object, d ⁱ _ck is the current nominal damage vector d ⁱ of the evaluated object The kth element of _c , they all represent the relevant information of the kth evaluated object, k=1,2,3,...,N in formula 4; m. If the elements of the identification vector B ⁱ are all 0, then get back to step f to continue this cycle; if the elements of the identification vector B ⁱ are not all 0, then enter the next step, namely step n; n. Calculate each element of the current initial damage vector d ⁱ⁺¹ _o of the evaluated object required for the next, ie i+1th cycle, according to formula 5; In formula 5, d ⁱ⁺¹ _ok is the kth element of the current initial damage vector d ⁱ⁺¹ _o of the evaluated object required for the next cycle, that is, the i+1th cycle, and d ⁱ _ok is this time, that is, the ith The k-th element of the current initial damage vector d ⁱ _o of the evaluated object in the second cycle, D ⁱ _uk is the k-th element of the unit change vector D ⁱ _u of the evaluated object in the i-th cycle, and B ⁱ _k is the i-th The kth element of the cyclic identification vector B ⁱ , k=1,2,3,...,N in formula 5; o. On the basis of the initial mechanical calculation benchmark model A _o , the support angular displacement constraint is first imposed on the cable structure support in A _o , and the value of the support angular displacement constraint is taken from the corresponding element in the support angular displacement vector V value, and then apply a temperature change to the cable structure in A _o , the value of the applied temperature change is taken from the steady-state temperature change vector S, and then let the health status of the cable be d ⁱ⁺¹ _o to get the next time, That is, the mechanical calculation benchmark model A ⁱ⁺¹ required for the i+1th cycle; after obtaining A ⁱ⁺¹ , obtain the current specific values of all monitored quantities in A ⁱ⁺¹ through mechanical calculations, and these specific values consist of The current initial value vector C ⁱ⁺¹ _o of the monitored quantity required for the next cycle, that is, the i+1th cycle; p. Take the current initial cable structure steady-state temperature data vector T ⁱ⁺¹ _o required for the next cycle, that is, the i+1th cycle, which is equal to the current initial cable structure steady-state temperature data vector T ⁱ _o of the i-th cycle; The current initial cable structure support angular coordinate vector U ⁱ⁺¹ _o required for the i+1th cycle is equal to the current initial cable structure support angular coordinate vector U ⁱ _o of the ith cycle; q. Go back to step f and start the next cycle.