CN117407953A

CN117407953A - Method, terminal and storage medium for calculating shear strength of anisotropic structural surface

Info

Publication number: CN117407953A
Application number: CN202311327108.7A
Authority: CN
Inventors: 袁维; 赖锡鹏; 孙瑞峰; 王伟; 林杭; 付晓东; 尹超; 张飞
Original assignee: Shijiazhuang Tiedao University
Current assignee: Shijiazhuang Tiedao University
Priority date: 2023-10-13
Filing date: 2023-10-13
Publication date: 2024-01-16

Abstract

The invention provides a method for calculating shear strength of a different structural surface, a terminal and a storage medium. The method comprises the following steps: acquiring a first single-axis compressive strength of a lower wall surface strength side and a second single-axis compressive strength of a higher wall surface strength side of two sides of a structural surface to be detected, and acquiring three-dimensional point cloud data of the structural surface to be detected; constructing a grid model with the shape height consistent with that of the structural surface to be detected according to the three-dimensional point cloud data, and extracting section lines on the grid model at equal intervals along the shearing direction of the structural surface to be detected; calculating the surface roughness coefficient of the structural surface corresponding to the structural surface to be measured according to the end point coordinate information of each line segment after discretizing each section line; calculating the structural surface combined wall surface strength of the structural surface to be measured according to the first single-axis compressive strength and the second single-axis compressive strength; and calculating the shear strength of the structural surface to be measured according to the surface roughness coefficient of the structural surface and the combined wall strength of the structural surface. The invention can calculate the shear strength of the anisotropic structural surface more accurately.

Description

Method, terminal and storage medium for calculating shear strength of anisotropic structural surface

Technical Field

The invention relates to the technical field of rock mass structural plane analysis, in particular to a method, a terminal and a storage medium for calculating shear strength of a different structural plane.

Background

The reason for the instability damage of the common building is mainly due to the fact that surrounding rock bodies slide and move or separate along a structural plane, so that a weak plane of the rock body is generally the structural plane, and in actual engineering, the rock body damage is mostly shear, and the shear strength of the structural plane is important to the stability evaluation of the rock body.

However, engineering rock mass is generally complicated in cause, the shape and the structural composition of a natural structural surface of the engineering rock mass have certain randomness, different structural surfaces with different rock wall surface strengths on two sides often exist in the rock mass, and even part of the area where the engineering is located is a complex stratum with a soft and hard interbedded structure. Therefore, the accurate calculation of the shear strength of the anisotropic structural surface is beneficial to the stability evaluation of the actual engineering rock mass.

Disclosure of Invention

The embodiment of the invention provides a method, a terminal and a storage medium for calculating the shear strength of a specific structural surface, which are used for solving the problem that the shear strength calculation is not accurate enough for the specific structural surface at present.

In a first aspect, an embodiment of the present invention provides a method for calculating shear strength of a structural surface with different characteristics, including:

acquiring a first single-axis compressive strength of a lower wall surface strength side and a second single-axis compressive strength of a higher wall surface strength side of two sides of a structural surface to be detected, and acquiring three-dimensional point cloud data of the structural surface to be detected;

Constructing a grid model with the shape height consistent with that of the structural surface to be detected according to the three-dimensional point cloud data, and extracting section lines on the grid model at equal intervals along the shearing direction of the structural surface to be detected;

calculating the surface roughness coefficient of the structural surface corresponding to the structural surface to be measured according to the end point coordinate information of each line segment after discretizing each section line;

calculating the structural surface combined wall surface strength of the structural surface to be detected according to the first single-axis compressive strength and the second single-axis compressive strength;

and calculating the shear strength of the structural surface to be measured according to the surface roughness coefficient of the structural surface and the combined wall strength of the structural surface.

In one possible implementation manner, the calculating the structural surface combined wall surface strength of the structural surface to be measured according to the first uniaxial compressive strength and the second uniaxial compressive strength includes:

calculating the ratio of the uniaxial compressive strength of two sides of the structural surface to be detected according to the first uniaxial compressive strength and the second uniaxial compressive strength;

and calculating the structural surface combined wall surface strength of the structural surface to be detected according to the ratio of the first uniaxial compressive strength to the uniaxial compressive strengths at the two sides.

In one possible implementation manner, the calculating the structural surface combined wall surface strength of the structural surface to be measured according to the ratio of the first uniaxial compressive strength and the two-sided uniaxial compressive strength includes:

According toCalculating the strength of the combined wall surface of the structural surface to be measured;

wherein CJCS is the structural face combined wall face strength of the structural face to be detected _{Low and low} And a is a first fitting coefficient, b is a second fitting coefficient, a and b are obtained through multi-element nonlinear fitting, and lambda is the ratio of the uniaxial compressive strengths of the two sides.

In one possible implementation manner, the calculating the shear strength of the structural surface to be measured according to the surface roughness coefficient of the structural surface and the combined wall strength of the structural surface includes:

according toCalculating the shear strength of the structural surface to be measured;

wherein τ _p For the shear strength of the structural surface to be measured, sigma _n In order to act on the normal stress of the structural face to be measured,and JRC is the surface roughness coefficient of the structural surface and CJCS is the combined wall strength of the structural surface for the basic friction angle of the structural surface to be measured.

In one possible implementation manner, the calculating the surface roughness coefficient of the structural surface corresponding to the structural surface to be measured according to the end point coordinate information of each line segment after discretizing each section line includes:

according to the end point coordinate information of each line segment of each section line, calculating a weighted average gradient and an accumulated relative fluctuation amplitude corresponding to each section line, wherein the weighted average gradient represents the friction effect of the structural surface to be tested, and the accumulated relative fluctuation amplitude represents the climbing effect of shearing of the structural surface to be tested;

Calculating the initial structural surface roughness coefficient corresponding to the structural surface to be measured according to each weighted average gradient and each accumulated relative fluctuation amplitude;

determining whether each line segment of each section line is a climbing segment or a non-climbing segment according to the end point coordinate information of each line segment of each section line;

calculating the shearing climbing rate corresponding to the structure surface to be measured according to the approximate length of each climbing section in all the sections corresponding to each section line and the approximate total length of all the sections corresponding to each section line;

calculating a section curvature coefficient corresponding to the structural surface to be measured according to the approximate length of each line segment corresponding to each section line and the actual length of each line segment corresponding to each section line;

and correcting the surface roughness coefficient of the initial structural surface according to the shearing climbing rate and the profile curvature coefficient to obtain the structural surface roughness coefficient corresponding to the structural surface to be detected.

In one possible implementation manner, the calculating the shear ramp rate corresponding to the structure to be measured according to the approximate length of each ramp segment in all segments corresponding to each section line and the approximate total length of all segments corresponding to each section line includes:

According toCalculating a shearing climbing rate corresponding to the structural surface to be detected;

wherein SCR is the shearing climbing rate corresponding to the structural surface to be tested, N is the line taking number of section lines, L _p For the approximate total length of all line segments corresponding to each section line, L _j+ For the approximate length of the j-th climbing section in all the sections corresponding to each section line, j=1, 2, … m, m is the total number of climbing sections in all the sections corresponding to each section line, L _k- For the approximate length of the kth non-climbing segment in all segments corresponding to each section line, k=1, 2, … w, w is the total number of non-climbing segments in all segments corresponding to each section line.

In one possible implementation manner, the calculating a section curvature coefficient corresponding to the structure to be measured according to the approximate length of each line segment corresponding to each section line and the actual length of each line segment corresponding to each section line includes:

according toCalculating a section curvature coefficient corresponding to the structural surface to be measured;

wherein CCP is the section curvature coefficient corresponding to the structure surface to be tested, N is the line taking number of the section lines, m is the total number of climbing sections in all the line sections corresponding to each section line, w is the total number of non-climbing sections in all the line sections corresponding to each section line, L _j+ The approximate length L of the j-th climbing section in all the sections corresponding to each section line _tj+ Corresponding to each section lineThe actual length of the j-th climbing segment of all segments of (a), j=1, 2, … m, L _k- For the approximate length of the kth non-climbing section in all the sections corresponding to each section line, L _tk- K=1, 2, … w, the actual length of the kth non-climbing segment of all segments corresponding to each section line.

In one possible implementation manner, the correcting the initial structural surface roughness coefficient according to the shear ramp rate and the profile curvature coefficient to obtain a structural surface roughness coefficient corresponding to the structural surface to be measured includes:

according toObtaining a structural surface roughness coefficient corresponding to the structural surface to be detected;

wherein JRC is the structural surface roughness coefficient corresponding to the structural surface to be measured, alpha is the correction coefficient, and JRC _{Initial initiation} And (3) for the initial structural surface roughness coefficient, SCR is the shearing climbing rate, CCP is the section curvature coefficient, c is a third fitting coefficient, d is a fourth fitting coefficient, e is a fifth fitting coefficient, and c, d and e are obtained through multi-element nonlinear fitting.

In a second aspect, an embodiment of the present invention provides a terminal, including a memory for storing a computer program and a processor for calling and running the computer program stored in the memory, to perform the steps of the method as described above in the first aspect or any possible implementation manner of the first aspect.

In a third aspect, embodiments of the present invention provide a computer readable storage medium storing a computer program which, when executed by a processor, implements the steps of the method as described above in the first aspect or any one of the possible implementations of the first aspect.

The embodiment of the invention provides a method, a terminal and a storage medium for calculating shear strength of an opposite structural surface, wherein the method comprises the steps of firstly obtaining first uniaxial compressive strength of a lower wall surface strength side and second uniaxial compressive strength of a higher wall surface strength side of two sides of a structural surface to be detected, and obtaining three-dimensional point cloud data of the structural surface to be detected; then constructing a grid model with the shape height consistent with that of the structural surface to be detected according to the three-dimensional point cloud data, and extracting section lines on the grid model at equal intervals in a shearing direction perpendicular to the structural surface to be detected; further, according to the end point coordinate information of each line segment after discretizing each section line, calculating the surface roughness coefficient of the structural surface corresponding to the structural surface to be measured; calculating the structural surface combined wall surface strength of the structural surface to be measured according to the first uniaxial compressive strength and the second uniaxial compressive strength; and calculating the shear strength of the structural surface to be measured according to the surface roughness coefficient of the structural surface and the combined wall strength of the structural surface. The method combines an optical information acquisition technology, computer science, finite difference numerical calculation and geotechnical test, is simple to operate, can convert empirical judgment into quantitative calculation, further accurately analyzes the shear strength of the anisotropic structural surface, avoids the defects of subjectivity and experience, and has important significance in engineering practice.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are needed in the embodiments or the description of the prior art will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a flow chart of an implementation of a method for calculating shear strength of an anisotropic structural surface according to an embodiment of the present invention;

FIG. 2 is a sample view of a core provided by an embodiment of the present invention;

FIG. 3 is a schematic diagram of a three-dimensional scanner scanning a surface of a structure to be measured according to an embodiment of the present invention;

FIG. 4 is a diagram of height information of a grid model corresponding to a structural plane to be tested according to an embodiment of the present invention;

FIG. 5 is a schematic illustration of equidistant cross-hatching along a shear direction on a mesh model provided by an embodiment of the present invention;

FIG. 6 is a schematic view of end point coordinates of a line segment after discretization of a section line according to an embodiment of the present invention;

FIG. 7 is a discretized schematic illustration of a section line provided by an embodiment of the present invention;

FIG. 8 is a schematic diagram of clipping a mesh model of a structural surface to be tested according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of a device for calculating shear strength of an anisotropic structural surface according to an embodiment of the present invention;

fig. 10 is a schematic diagram of a terminal according to an embodiment of the present invention.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth such as the particular system architecture, techniques, etc., in order to provide a thorough understanding of the embodiments of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.

For the purpose of making the objects, technical solutions and advantages of the present invention more apparent, the following description will be made by way of specific embodiments with reference to the accompanying drawings.

Referring to fig. 1, a flowchart of an implementation of a method for calculating shear strength of an anisotropic structural surface according to an embodiment of the present invention is shown, and details are as follows:

in step 101, a first uniaxial compressive strength of a lower wall surface strength side and a second uniaxial compressive strength of a higher wall surface strength side of two sides of a structural surface to be measured are obtained, and three-dimensional point cloud data of the structural surface to be measured are obtained.

The structural surface to be measured can be a rock structural surface of a research area in the stratum to be measured. Because the structural surface to be measured is the opposite structural surface with different rock wall surface intensities at two sides, after the structural surface to be measured is determined, the size of the structural surface can be determined, and a conventional geotechnical test can be performed by sampling to obtain the first uniaxial compressive strength of the lower side of the wall surface intensity and the second uniaxial compressive strength of the higher side of the wall surface intensity in the two sides of the structural surface to be measured.

By way of example, the sample may be taken by a core drill, and the sample may be a cylinder having a diameter of 5cm and a height of 10cm as shown in fig. 2.

The conventional geotechnical test performed on the test sample may include a uniaxial compressive test to obtain a first uniaxial compressive strength of a lower side of wall strength and a second uniaxial compressive strength of a higher side of wall strength in both sides of the structural surface to be tested through the uniaxial compressive test. For example, a uniaxial compression test may be performed by a rebound tester.

In addition, conventional geotechnical tests performed on specimens may also include density tests and straight structure direct shear tests in order to facilitate subsequent calculation of shear strength. The weight density of the upper soil of the structural surface to be measured can be obtained by carrying out a density test on the sample, and the basic friction angle of the structural surface to be measured can be reversely calculated by carrying out a straight structure direct shear test on the sample.

Then, a three-dimensional scanner such as a structured light scanner shown in fig. 3 can be used to scan the structural surface to be measured and obtain a three-dimensional point cloud data file containing geometric shape information of the structural surface to be measured.

In step 102, a grid model with the shape height consistent with that of the structural surface to be measured is constructed according to the three-dimensional point cloud data, and section lines are extracted from the grid model at equal intervals along the shearing direction of the structural surface to be measured.

In step 103, according to the end point coordinate information of each line segment after discretizing each section line, the surface roughness coefficient of the structural surface corresponding to the structural surface to be measured is calculated.

Based on the three-dimensional point cloud data obtained in step 101, in order to quantitatively calculate the surface roughness coefficient of the structural surface corresponding to the structural surface to be measured, the three-dimensional point cloud data may be imported into reverse engineering software such as Rhino software to construct a structural surface grid (i.e., a grid model with a height consistent with the shape of the structural surface to be measured). And then, section lines can be extracted from the grid model at equal intervals according to the shearing direction of the structural surface to be detected.

For example, the height information diagram of the grid model corresponding to the structural surface to be tested is shown in fig. 4, section lines are extracted from the grid model at equal intervals along the shearing direction of the structural surface to be tested, that is, the structural surface to be tested is sectioned along the x-axis direction, and the obtained section lines are shown in fig. 5.

For simplifying the calculation and facilitating the practical application, the number of the section lines may be more than 10, for example, the section lines in fig. 5 are 11.

Then, discretizing treatment can be carried out on each section line, and end point coordinate information of each line segment on each section line after discretization is obtained, so that the surface roughness coefficient of the structural surface corresponding to the structural surface to be measured can be quantitatively calculated based on the end point coordinate information.

When discretizing each section line, discretization may be performed at equal intervals. In order to make the surface roughness coefficient of the structural surface calculated later more approximate to the actual value, the section line is generally divided into at least 120 line segments at equal intervals. By way of example, each section line may be equally spaced into 140 line segments.

As shown in fig. 6, the coordinate information of the end point of each line segment on each section line is x-coordinate information and z-coordinate information of the end point of each line segment, wherein the x-coordinate information represents the position information of the end point of the line segment in the shearing direction, and the z-coordinate information represents the height information of the end point of the line segment.

Wherein, when constructing the structural surface grid, the maximum length of the grid line is smaller than the length of the discretized single line segment, and the smaller the length of the grid line is, the higher the accuracy of the subsequent calculation of the surface roughness coefficient of the structural surface is.

Optionally, calculating the structural surface roughness coefficient corresponding to the structural surface to be measured according to the end point coordinate information of each line segment after discretizing each section line may include:

according to the end point coordinate information of each line section of each section line, calculating a weighted average gradient and an accumulated relative fluctuation amplitude corresponding to each section line, wherein the weighted average gradient represents the friction effect of the structural surface to be tested, and the accumulated relative fluctuation amplitude represents the climbing effect of the shearing of the structural surface to be tested.

And calculating the initial structural surface roughness coefficient corresponding to the structural surface to be measured according to each weighted average gradient and each accumulated relative fluctuation amplitude.

And determining whether each line segment of each section line is a climbing segment or a non-climbing segment according to the end point coordinate information of each line segment of each section line.

And calculating the shearing climbing rate corresponding to the structure surface to be measured according to the approximate length of each climbing section in all the sections corresponding to each section line and the approximate total length of all the sections corresponding to each section line.

And calculating a section curvature coefficient corresponding to the structural surface to be measured according to the approximate length of each line segment corresponding to each section line and the actual length of each line segment corresponding to each section line.

And correcting the surface roughness coefficient of the initial structural surface according to the shearing climbing rate and the profile curvature coefficient to obtain the surface roughness coefficient of the structural surface corresponding to the structural surface to be detected.

In this embodiment, in order to make the calculated surface roughness coefficient of the structural surface closer to the true value, parameters capable of characterizing the mechanical characteristics of the structural surface shear, namely, the weighted average gradient and the cumulative relative relief amplitude, are introduced. The weighted average gradient represents the friction effect of the structural surface to be tested, and the accumulated relative fluctuation amplitude represents the climbing effect of the shearing of the structural surface to be tested.

Specifically, for each section line, its corresponding weighted average gradient WAG and cumulative relative heave amplitude CRRA can be calculated according to the following equation:

wherein z is _i+1 -z _i Is the difference of height information and x in the coordinate information of two adjacent endpoints _i+1 -x _i For the position information difference (namely, the corresponding discretization interval when the section lines are discretized at equal intervals) in the coordinate information of two adjacent end points, n is the total number of the end points of all the line segments obtained after discretizing each section line, and L is the position information of each section lineProjection length in the shear direction.

After calculating the weighted average gradient WAG and the accumulated relative fluctuation amplitude CRRA corresponding to each section line, calculating the average value of the weighted average gradient WAG corresponding to each section line to obtain WAG _{Are all} And calculating an average value of the accumulated relative fluctuation amplitudes CRRA corresponding to each section line to obtain CRRA _{Are all} Further according toAnd calculating the initial structural surface roughness coefficient corresponding to the structural surface to be measured. Wherein p is ₁ 、p ₂ 、p ₃ Is an empirical coefficient, which can be determined by fitting. And p is ₁ 、p ₂ 、p ₃ But also on the number of line segments obtained after discretization of the section line. Exemplary, empirical coefficients for discretization of the section line into 140 line segments are shown in Table 1:

TABLE 1 empirical coefficients corresponding to 140 line segments

On the basis, in order to make the calculated surface roughness coefficient of the structural surface more accurate, the influence of the morphological characteristics and the contact condition of the structural surface on the surface roughness coefficient of the structural surface is further considered.

On the one hand, the whole structure surface is provided with a climbing section and a non-climbing section from a macroscopic view, and the non-climbing section of the through structure surface is a non-contact area in the shearing process, so that the contribution to the shearing strength is very little, and the shearing climbing rate corresponding to the structure surface to be detected is calculated according to the approximate length of each climbing section in all the line sections corresponding to each section line and the approximate total length of all the line sections corresponding to each section line, so that the contribution of the climbing section of the structure surface to be detected is measured.

On the other hand, the straight smooth line segment after discretization of the section line is considered to be different from the real section line, and certain morphological difference exists between the straight smooth line segment and the real section line, so that the bending condition of the structural surface is quantitatively represented on a two-dimensional space formed by the shearing direction corresponding to the section line and the height direction, namely, the section curvature coefficient corresponding to the structural surface to be detected is calculated according to the approximate total length of all line segments corresponding to each section line and the actual total length of all line segments corresponding to each section line, and then the initial structural surface roughness coefficient is corrected according to the shearing climbing rate and the section curvature coefficient, so that the more accurate structural surface roughness coefficient corresponding to the structural surface to be detected is obtained.

Optionally, with reference to fig. 7, calculating the shear ramp rate corresponding to the structure to be measured according to the approximate length of each ramp segment in all segments corresponding to each section line and the approximate total length of all segments corresponding to each section line may include:

according toAnd calculating the shearing climbing rate corresponding to the structure surface to be measured.

Similarly, calculating the profile curvature coefficient corresponding to the structure surface to be measured according to the approximate length of each line segment corresponding to each section line and the actual length of each line segment corresponding to each section line may include:

according toAnd calculating a section curvature coefficient corresponding to the structure surface to be measured.

Wherein CCP is the section curvature coefficient corresponding to the structure surface to be tested, N is the line taking number of the section lines, and m is the line segments corresponding to each section lineThe total number of climbing sections, w is the total number of non-climbing sections in all sections corresponding to each section line, L _j+ The approximate length L of the j-th climbing section in all the sections corresponding to each section line _tj+ For the actual length of the j-th climbing section in all the sections corresponding to each section line, j=1, 2, … m, L _k- For the approximate length of the kth non-climbing section in all the sections corresponding to each section line, L _tk- K=1, 2, … w, the actual length of the kth non-climbing segment of all segments corresponding to each section line.

It should be noted that, the above embodiment only provides an example of calculating the shear ramp rate and the profile curvature coefficient corresponding to the structural surface to be tested, and according to actual needs, a corresponding shear ramp rate and a profile curvature coefficient may be calculated for each section line, and then the shear ramp rate and the profile curvature coefficient corresponding to each section line are averaged to obtain the shear ramp rate and the profile curvature coefficient corresponding to the structural surface to be tested, which is not limited in this embodiment.

In addition, in determining whether each line segment of each section line is a climbing segment or a non-climbing segment, the determination may be made based on the height information in the end point coordinate information of each line segment. In particular, if z _i+1 ≥z _i The line segment between the endpoint i and the endpoint i+1 is described as a climbing segment, if z _i+1 <z _i And (3) describing that the line segment between the endpoint i and the endpoint i+1 is a non-climbing segment.

Optionally, correcting the initial structural surface roughness coefficient according to the shearing ramp rate and the profile curvature coefficient to obtain the structural surface roughness coefficient corresponding to the structural surface to be detected, which may include:

According toAnd obtaining the surface roughness coefficient of the structural surface corresponding to the structural surface to be detected.

Wherein JRC is the structural surface roughness coefficient corresponding to the structural surface to be measured, alpha is the correction coefficient, and JRC _{Initial initiation} The surface roughness coefficient of the initial structural surface is calculated by SCR, the shearing climbing rate is calculated by SCR,CCP is the profile curvature coefficient, c is the third fitting coefficient, d is the fourth fitting coefficient, e is the fifth fitting coefficient, and c, d and e are obtained by multi-element nonlinear fitting.

Illustratively, c may be 1.33627 + -0.06527, d may be-1.44066 + -0.18493, and e may be 2.18654 + -0.18819.

In step 104, the structural surface combined wall surface strength of the structural surface to be measured is calculated according to the first uniaxial compressive strength and the second uniaxial compressive strength.

In this embodiment, when the structural surface to be measured is an opposite structural surface, subjective and empirical errors exist in the existing shear strength calculation method, so that the characteristics of different wall strengths on two sides of the opposite structural surface are combined, and the first uniaxial compressive strength on the lower side of the wall strength and the second uniaxial compressive strength on the higher side of the wall strength in the opposite structural surface are obtained, and then the structural surface combined wall strength is calculated according to the first uniaxial compressive strength and the second uniaxial compressive strength, so that the shear strength is calculated more accurately based on the structural surface combined avoidance strength.

Optionally, calculating the structural surface combined wall surface strength of the structural surface to be measured according to the first uniaxial compressive strength and the second uniaxial compressive strength may include: calculating the ratio of the uniaxial compressive strength of two sides of the structural surface to be tested according to the first uniaxial compressive strength and the second uniaxial compressive strength; and calculating the structural surface combined wall surface strength of the structural surface to be measured according to the ratio of the first uniaxial compressive strength to the uniaxial compressive strengths at the two sides.

In this embodiment, the shear strength of the test can be obtained by performing a straight structure direct shear test on the test sample, so that the uniaxial compressive strength of the test sample can be reversely calculated based on the Barton empirical formula, and since the structural surface to be tested is an opposite structural surface, the uniaxial compressive strength of the reversely calculated test sample is equivalent to the structural surface combined wall surface strength of the structural surface to be tested. Then, based on the calculated structural face combined wall face strength and the first uniaxial compressive strength and the second uniaxial compressive strength obtained by the uniaxial compressive test, the ratio of the structural face combined wall face strength to the both-side uniaxial compressive strength and the first uniaxial compressive strength can be determined.

Wherein the ratio of uniaxial compressive strength on both sidesWherein, JCS _{Low and low} JCS is the first uniaxial compressive strength _{High height} Is the second uniaxial compressive strength.

Optionally, calculating the structural surface combined wall surface strength of the structural surface to be measured according to the ratio of the first uniaxial compressive strength and the uniaxial compressive strengths of the two sides may include:

according toAnd calculating the strength of the combined wall surface of the structural surface to be measured.

Wherein CJCS is the structural face combined wall face strength of the structural face to be detected _{Low and low} The method is characterized in that the method is used for preparing the composite material with the two sides and comprises the steps of taking the composite material as a first uniaxial compressive strength, taking a first fitting coefficient, taking b as a second fitting coefficient, taking a and b through multi-element nonlinear fitting, and taking lambda as the ratio of uniaxial compressive strengths on two sides.

In this embodiment, after the structural surface combined wall strength, the first uniaxial compressive strength, and the second uniaxial compressive strength of the sample are obtained, the relationship between the structural surface combined wall strength and the first uniaxial compressive strength, the second uniaxial compressive strength can be determined asWherein, through the multi-element nonlinear fitting, the correlation (characterized by variance) between the fitting result and the actual result is 0.84432 when a is 0.62361 and b is-1.10176, namely, the fitting result is better. It can thus be determined that the first fitting coefficient a is 0.62361 and the second fitting coefficient b is-1.10176.

In order to make the fitting result better, the subsequent calculation result is more accurate, and the multi-element nonlinear fitting can be further performed, so as to determine more accurate values of the first fitting coefficient a and the second fitting coefficient b.

In step 105, the shear strength of the structural surface to be measured is calculated according to the surface roughness coefficient of the structural surface and the combined wall strength of the structural surface.

In this embodiment, according to the surface roughness coefficient of the structural surface and the combined wall surface strength of the structural surface determined by the above steps, in combination with Barton's empirical formula, the shear strength of the structural surface to be measured, that is, the peak shear strength of the structural surface to be measured, can be more accurately calculated, and further, a peak shear strength calculation method is provided for the heterogeneous structural surface of rock in the complex bottom layer so as to facilitate stability analysis.

Optionally, calculating the shear strength of the structural surface to be measured according to the surface roughness coefficient of the structural surface and the combined wall strength of the structural surface may include:

According toAnd calculating the shear strength of the structural surface to be measured.

Wherein τ _p For the shear strength of the structural surface to be measured, sigma _n In order to act on the normal stress of the structural face to be measured,for the basic friction angle of the structural surface to be measured, JRC is the surface roughness coefficient of the structural surface, and CJCS is the combined wall strength of the structural surface.

The embodiment improves the Barton empirical formula based on the structural surface combined wall surface strength CJCS, and in the improved formula, the basic friction angle of the structural surface to be detectedCan be determined by the straight structure direct shear test described above. In addition, the normal stress sigma acting on the structural surface to be measured is required _n Wherein, according to working conditions, theAnd calculating the earth pressure of the upper layer of the structural surface to be measured to obtain the normal stress acting on the structural surface to be measured.

Specifically, the upper soil pressure of the structural surface to be measured is calculated, so that the normal stress acting on the structural surface to be measured is obtained, and the expression is as follows:

wherein gamma is the weight density of soil, which can be obtained by the density test, H is the thickness of the soil, F is the external load on the upper part of the soil, P is the vertical pressure of the soil acting on the structural surface to be tested, S is the area of the structural surface to be tested, sigma _n Is the normal stress acting on the structural surface.

And (3) bringing the normal stress acting on the structural surface, the basic friction angle of the structural surface to be detected, the surface roughness coefficient of the structural surface and the combined wall surface strength of the structural surface into an improved formula to calculate the peak shear strength of the structural surface to be detected.

The method for calculating the shear strength of the anisotropic structural surface provided by the embodiment of the invention is further described by a specific example as follows:

(1) Firstly, researching by selecting a rock joint of a special stratum in a certain area through field investigation, selecting a cement mortar shearing test block with a proper mixing ratio, pouring the cement mortar shearing test block similar to the rock property, reserving the sample, carrying out a uniaxial compression test and a density test to obtain basic mechanical parameters (see table 2), and carrying out shearing strength analysis of a different structural surface by using code combination L-L, L-M, L-H, M-M, M-H, H-H to represent each test block, wherein L represents soft rock, M represents softer rock, H represents harder rock and a basic friction angle of the structural surface corresponding to the strength combinationFirst uniaxial compressive Strength JCS _{Low and low} The ratio lambda of uniaxial compressive strength on both sides is shown in Table 3.

TABLE 2 basic mechanical parameters of artificial rock mass

Species of type	Water: ash: sand	Uniaxial compressive Strength/Mpa	Density kg/m3
				Soft (L)	1:2:2	14.82	2124
Softer (M)	1:2.5:1.8	25.70	2200
				Harder (H)	1:3:2	35.21	2237

TABLE 3 basic Friction angle of different structural surfaces under different intensity combinations

Intensity combination	L-L	L-M	L-H	M-M	M-H	H-H
							Basic friction angle/°	30.4	31.13	31.45	32.48	33.27	34.35
JCS _{Low and low} /MPa	14.82	14.82	14.82	25.70	25.70	35.21
							λ	1	1.73	2.38	1	1.37	1

(2) And scanning and recording the surface morphology of the different structural surfaces with different intensity combinations by using an EinScan-Pro handheld high-precision scanner, and converting the scanning data into high-precision point cloud data.

(3) The point cloud data is imported into the Rhino, and three shearing directions of 0 degree, 30 degrees and 60 degrees are selected as a research area (the specific engineering can be automatically sized according to specifications) in the area of the graph 8 to be cut. Wherein, because the structure surface is scanned to obtain an irregular graph, the structure surface is cut according to the ellipse-like shape shown in fig. 8, thereby facilitating rotation

(4) According to the recommendation, for each shearing direction of three shearing directions of 0 degree, 30 degree and 60 degree, extracting 11 section lines to divide the structural surface into 10 equal-width areas (as shown in fig. 5), discretizing each section line into 140 line segments, and calculating initial structural surface roughness coefficient JRC in the three shearing directions of 0 degree, 30 degree and 60 degree by a mode of step 103 _{Initial initiation} 7.82, 7.23, 6.42 respectively. And then calculating the shearing climbing rate and the section curvature coefficient in the three shearing directions of 0 degree, 30 degrees and 60 degrees, and further obtaining the surface roughness coefficient JRC of the structural surface in the three shearing directions of 0 degree, 30 degrees and 60 degrees.

(5) The simulation working condition is normal stress sigma of the upper soil pressure acting on the structural surface _n 1 MPa.

Adopts the technical proposal to lead sigma _n 、JRC、CJCS brings in formulaPeak shear strength calculations with good reliability (see table 4) can be obtained and provide a reference for subsequent rock stability analysis.

TABLE 4 peak shear Strength calculation (MPa) for different structural planes under different Strength combinations

According to the embodiment of the invention, the first uniaxial compressive strength of the lower side of the wall surface strength and the second uniaxial compressive strength of the higher side of the wall surface strength in the two sides of the structural surface to be detected are firstly obtained, and the three-dimensional point cloud data of the structural surface to be detected are obtained; then constructing a grid model with the shape height consistent with that of the structural surface to be detected according to the three-dimensional point cloud data, and extracting section lines on the grid model at equal intervals in a shearing direction perpendicular to the structural surface to be detected; further, according to the end point coordinate information of each line segment after discretizing each section line, calculating the surface roughness coefficient of the structural surface corresponding to the structural surface to be measured; calculating the structural surface combined wall surface strength of the structural surface to be measured according to the first uniaxial compressive strength and the second uniaxial compressive strength; and calculating the shear strength of the structural surface to be measured according to the surface roughness coefficient of the structural surface and the combined wall strength of the structural surface. The method combines an optical information acquisition technology, computer science, finite difference numerical calculation and geotechnical test, is simple to operate, can convert empirical judgment into quantitative calculation, further accurately analyzes the shear strength of the anisotropic structural surface, avoids the defects of subjectivity and experience, and has important significance in engineering practice.

It should be understood that the sequence number of each step in the foregoing embodiment does not mean that the execution sequence of each process should be determined by the function and the internal logic, and should not limit the implementation process of the embodiment of the present invention.

The following are device embodiments of the invention, for details not described in detail therein, reference may be made to the corresponding method embodiments described above.

Fig. 9 is a schematic structural diagram of a device for calculating shear strength of an anisotropic structural surface according to an embodiment of the present invention, and for convenience of explanation, only the portions related to the embodiment of the present invention are shown, which are described in detail below:

as shown in fig. 9, the anisotropic structural surface shear strength calculation device includes: an acquisition module 91, a first processing module 92, a second processing module 93, a third processing module 94 and a fourth processing module 95.

An obtaining module 91, configured to obtain a first uniaxial compressive strength of a lower wall surface strength side and a second uniaxial compressive strength of a higher wall surface strength side of two sides of the structural surface to be measured, and obtain three-dimensional point cloud data of the structural surface to be measured;

the first processing module 92 is configured to construct a grid model with a height consistent with the shape of the structural surface to be tested according to the three-dimensional point cloud data, and extract section lines on the grid model at equal intervals along the shearing direction of the structural surface to be tested;

The second processing module 93 is configured to calculate a structural surface roughness coefficient corresponding to the structural surface to be measured according to the end point coordinate information of each line segment after discretizing each section line;

the third processing module 94 is configured to calculate a structural surface combined wall surface strength of the structural surface to be measured according to the first uniaxial compressive strength and the second uniaxial compressive strength;

and the fourth processing module 95 is configured to calculate the shear strength of the structural surface to be measured according to the surface roughness coefficient of the structural surface and the combined wall strength of the structural surface.

In one possible implementation, the third processing module 94 may be configured to calculate a ratio of uniaxial compressive strengths of two sides of the structural surface to be measured according to the first uniaxial compressive strength and the second uniaxial compressive strength;

In one possible implementation, the third processing module 94 may be configured to, according toCalculating the strength of the combined wall surface of the structural surface to be measured;

the CJCS is the structural surface combined wall surface strength of the structural surface to be detected, JCS is low in the first uniaxial compressive strength, a is a first fitting coefficient, b is a second fitting coefficient, a and b are obtained through multi-element nonlinear fitting, and lambda is the ratio of the uniaxial compressive strengths of the two sides.

In one possible implementation, the fourth processing module 95 may be configured to, according toCalculating the shear strength of the structural surface to be measured;

In a possible implementation manner, the second processing module 93 may be configured to calculate, according to the end point coordinate information of each line segment of each section line, a weighted average gradient corresponding to each section line, where the weighted average gradient represents a friction effect of the structural plane to be measured, and an accumulated relative heave amplitude represents a climbing effect of shearing of the structural plane to be measured;

In a possible implementation, the second processing module 93 may be configured to, according toCalculating a shearing climbing rate corresponding to the structural surface to be detected;

In a possible implementation, the second processing module 93 may be configured to, according toCalculating a section curvature coefficient corresponding to the structural surface to be measured;

wherein CCP is the section curvature coefficient corresponding to the structure surface to be tested, N is the line taking number of the section lines, m is the total number of climbing sections in all the line sections corresponding to each section line, w is the total number of non-climbing sections in all the line sections corresponding to each section line, L _j+ The approximate length L of the j-th climbing section in all the sections corresponding to each section line _tj+ For the actual length of the j-th climbing section in all the sections corresponding to each section line, j=1, 2, … m, L _k- For the approximate length of the kth non-climbing section in all the sections corresponding to each section line, L _tk- K=1, 2, … w, the actual length of the kth non-climbing segment of all segments corresponding to each section line.

In a possible implementation, the second processing module 93 may be configured to, according toObtaining a structural surface roughness coefficient corresponding to the structural surface to be detected;

Fig. 10 is a schematic diagram of a terminal according to an embodiment of the present invention. As shown in fig. 10, the terminal 10 of this embodiment includes: a processor 100, a memory 101, and a computer program 102 stored in the memory 101 and executable on the processor 100. The processor 100, when executing the computer program 102, implements the steps of the above-described embodiments of the method for calculating shear strength of the anisotropic structure surface, such as steps 101 to 105 shown in fig. 1. Alternatively, the processor 100, when executing the computer program 102, performs the functions of the modules/units in the above-described apparatus embodiments, for example, the functions of the modules/units 91 to 95 shown in fig. 9.

By way of example, computer program 102 may be partitioned into one or more modules/units that are stored in memory 101 and executed by processor 100 to accomplish the present invention. One or more of the modules/units may be a series of computer program instruction segments capable of performing particular functions to describe the execution of the computer program 102 in the terminal 10. For example, the computer program 102 may be split into modules/units 91 to 95 shown in fig. 9.

The terminal 10 may be a computing device such as a desktop computer, a notebook computer, a palm top computer, a cloud server, etc. The terminal 10 may include, but is not limited to, a processor 100, a memory 101. It will be appreciated by those skilled in the art that fig. 10 is merely an example of the terminal 10 and is not intended to limit the terminal 10, and may include more or fewer components than shown, or may combine certain components, or different components, e.g., the terminal may further include an input-output device, a network access device, a bus, etc.

The processor 100 may be a central processing unit (Central Processing Unit, CPU), but may also be other general purpose processors, digital signal processors (Digital Signal Processor, DSP), application specific integrated circuits (Application Specific Integrated Circuit, ASIC), field programmable gate arrays (Field-Programmable Gate Array, FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The memory 101 may be an internal storage unit of the terminal 10, such as a hard disk or a memory of the terminal 10. The memory 101 may also be an external storage device of the terminal 10, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card) or the like, which are provided on the terminal 10. Further, the memory 101 may also include both internal storage units and external storage devices of the terminal 10. The memory 101 is used to store computer programs and other programs and data required by the terminal. The memory 101 may also be used to temporarily store data that has been output or is to be output.

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-described division of the functional units and modules is illustrated, and in practical application, the above-described functional distribution may be performed by different functional units and modules according to needs, i.e. the internal structure of the apparatus is divided into different functional units or modules to perform all or part of the above-described functions. The functional units and modules in the embodiment may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit, where the integrated units may be implemented in a form of hardware or a form of a software functional unit. In addition, specific names of the functional units and modules are only for convenience of distinguishing from each other, and are not used for limiting the protection scope of the present application. The specific working process of the units and modules in the above system may refer to the corresponding process in the foregoing method embodiment, which is not described herein again.

In the foregoing embodiments, the descriptions of the embodiments are emphasized, and in part, not described or illustrated in any particular embodiment, reference is made to the related descriptions of other embodiments.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

In the embodiments provided in the present invention, it should be understood that the disclosed apparatus/terminal and method may be implemented in other manners. For example, the apparatus/terminal embodiments described above are merely illustrative, e.g., the division of modules or units is merely a logical functional division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection via interfaces, devices or units, which may be in electrical, mechanical or other forms.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed over a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in the embodiments of the present invention may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The integrated modules/units, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a computer readable storage medium. Based on such understanding, the present invention may implement all or part of the flow of the method of the above embodiment, or may be implemented by instructing related hardware by a computer program, where the computer program may be stored in a computer readable storage medium, and the computer program may implement the steps of the method embodiment of the above specific structural surface shear strength calculation method when executed by a processor. Wherein the computer program comprises computer program code, which may be in the form of source code, object code, executable files or in some intermediate form, etc. The computer readable medium may include: any entity or device capable of carrying computer program code, a recording medium, a U disk, a removable hard disk, a magnetic disk, an optical disk, a computer Memory, a Read-Only Memory (ROM), a random access Memory (Random Access Memory, RAM), an electrical carrier signal, a telecommunications signal, a software distribution medium, and so forth.

The above embodiments are only for illustrating the technical solution of the present invention, and are not limiting; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present invention, and are intended to be included in the scope of the present invention.

Claims

1. The method for calculating the shear strength of the anisotropic structural surface is characterized by comprising the following steps of:

2. The method for calculating the shear strength of the opposite structural surface according to claim 1, wherein calculating the structural surface combined wall strength of the structural surface to be measured according to the first uniaxial compressive strength and the second uniaxial compressive strength comprises:

3. The method for calculating the shear strength of the opposite structural surface according to claim 2, wherein calculating the structural surface combined wall strength of the structural surface to be measured according to the ratio of the first uniaxial compressive strength to the uniaxial compressive strengths of the two sides comprises:

4. The method for calculating the shear strength of the opposite structural surface according to claim 1, wherein calculating the shear strength of the structural surface to be measured according to the surface roughness coefficient of the structural surface and the combined wall strength of the structural surface comprises:

wherein τ _p For the shear strength of the structural surface to be measured, sigma _n In order to act on the normal stress of the structural face to be measured,is the basic friction of the structural surface to be measuredAnd the angle JRC is the surface roughness coefficient of the structural surface, and the CJCS is the combined wall strength of the structural surface.

5. The method for calculating the shear strength of the opposite structural surface according to claim 1, wherein calculating the surface roughness coefficient of the structural surface corresponding to the structural surface to be measured according to the end point coordinate information of each line segment after discretizing each section line comprises:

6. The method for calculating the shear strength of the anisotropic structural surface according to claim 5, wherein calculating the shear ramp rate corresponding to the structural surface to be measured according to the approximate length of each ramp segment in all segments corresponding to each section line and the approximate total length of all segments corresponding to each section line comprises:

wherein SCR is the shearing climbing rate corresponding to the structural surface to be tested, N is the line taking number of section lines, L _p For the approximate total length of all line segments corresponding to each section line, L _j+ For the approximate length of the j-th climbing section in all the sections corresponding to each section line, j=1, 2, … m, m is the total number of climbing sections in all the sections corresponding to each section line, L _k -for the approximate length of the kth non-climbing segment of all segments corresponding to each section line, k=1, 2, … w, w being the total number of non-climbing segments of all segments corresponding to each section line.

7. The method for calculating the shear strength of a structural surface according to claim 5, wherein calculating the section curvature coefficient corresponding to the structural surface to be measured according to the approximate length of each line segment corresponding to each section line and the actual length of each line segment corresponding to each section line comprises:

8. The method for calculating the shear strength of a different structural surface according to claim 5, wherein the step of correcting the initial structural surface roughness coefficient according to the shear ramp rate and the profile curvature coefficient to obtain a structural surface roughness coefficient corresponding to the structural surface to be measured comprises the steps of:

9. A terminal comprising a memory for storing a computer program and a processor for invoking and running the computer program stored in the memory to perform the method of any of claims 1 to 8.

10. A computer readable storage medium storing a computer program, characterized in that the computer program when executed by a processor implements the steps of the method according to any of the preceding claims 1 to 8.