JP2006214101A - Hole-curvature measuring apparatus and chemical-agent injection method using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small-diameter and high-precision hole-curvature measuring apparatus which can be used by being inserted into an injection outer pipe, an upward borehole or the like, and a chemical-agent injection method using the apparatus. <P>SOLUTION: In the hole-curvature measuring apparatus, a triaxial magnetic sensor 11, a triaxial acceleration sensor 13, a signal processing circuit part 12, a power supply circuit and a signal transmission circuit part 14 are internally provided in a cylindrical container 10 of a nonmagnetic material. In the structure of each magnetic sensor of the triaxial magnetic sensor, a rod-shaped core material, around which a coil is wound, is fixed by means of a silicon material, and further fixed in the state of being put into a holder so as to prevent a deviation in shaft arrangement from being caused by vibrations. In the chemical-agent injection method, a casing 1 is pulled out by erecting the injection outer pipe 2 after casing drilling; after that, hole curvature is measured by inserting the hole-curvature measuring apparatus 5 into the injection outer pipe 2; and subsequently, a chemical agent is injected by erecting an injection inner pipe with a packer into the injection outer pipe 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a small hole bending measuring device and a chemical injection method using the device.

  The chemical injection method as a ground improvement method is to inject solidified material (grouting) into the ground to create consolidated soil, thereby reducing the water permeability of the ground and strengthening the ground. As one example, a double pipe double packer method is known.

6 and 7 show the construction procedure of this double pipe double packer method. First, as shown in FIG. 7A, the ground is drilled to a predetermined depth by a drilling machine (rotary boring machine or rotary percussion) 4. This hole is usually made by the casing 1 for protecting the hole wall and installing an injection outer pipe to be described later (casing hole drilling process: see FIG. 6A).
Next, the bending from the planned angle of the hole (inclination angle from the vertical angle) is measured using a gyro-type measuring device (hole bending measurement process: see FIGS. 6B-1 and 7B-1). .
Next, as shown in FIG. 7C, the casing 1 is filled with a seal grout. That is, the muddy water is changed to the sealing liquid (CB liquid) to fill the hole (substitution process for replacing the muddy water with the sealing liquid: see FIG. 6C). This seal grout is filled by inserting a flexible pipe to the bottom of the hole.
Thereafter, as shown in FIG. 7 (d), the outer injection pipe 2 whose tip is closed with a cap is built in the casing 1, and the casing 1 is pulled out (the process of pulling out the casing after the injection outer pipe is built: FIG. 6 (d)).

  The above steps (a) to (d) are repeated to drill all holes (see FIGS. 6 (e) and 7 (e)). At this time, the casing 1 pulled out in the step (d) is used for opening a hole at another location.

  Next, as shown in FIG. 7 (f), an injection inner tube with a packer (injection hose) with a double packer attached to the tip is built into the injection outer tube 2 to form a double tube. Then, the injection inner tube is moved in the axial direction so that the injection hole of the injection inner tube coincides with the deepest injection hole of the injection outer tube, the chemical liquid is pumped from the ground, and the chemical liquid is injected into the ground from the injection hole (CB) Liquid injection implementation step: see FIG. 6 (f)).

  Next, by moving the injection inner pipe upward, the injection hole is aligned with the injection hole directly above, and the chemical solution is injected from the injection hole into the ground (see FIG. 7G). This process is sequentially performed up to the uppermost injection hole, and a chemical solution is injected into the ground from each injection hole (see FIG. 7 (h)).

  As described above, in the double-pipe double packer method, a large number of casing holes are drilled, each responsible for a predetermined small area ground improvement range A (see FIG. 7 (a)), and as a whole wider predetermined It is intended to improve the ground of the range. For this reason, it is very important to know the degree of inclination (hole bending) of the drilled hole in order to inject and adjust the chemical solution so that it spreads uniformly over a predetermined ground improvement range.

Conventionally, as a device for measuring this hole bending, a gyro-type measuring device using a gyrocompass capable of triaxial measurement (vertical angle 0 to 360 °), for example, as shown in Patent Document 1, 2. Description of the Related Art There is known a drilling information measuring device in which an azimuth meter, an azimuth signal processing unit, an inclinometer, an inclination signal processing unit, a memory unit, and a battery unit are provided in a nonmagnetic cylindrical housing from the rod tip side. In the drilling information measuring apparatus of Patent Document 1, the inclinometer is configured as a two-axis inclinometer in which two acceleration sensors are arranged orthogonally to the X-axis direction and the Y-axis direction, respectively, and the compass is an electronic magnetic compass. It is comprised by.
Japanese Patent Laid-Open No. 10-148084

  In general, when performing oblique boring with a chemical injection method or the like, it is necessary to measure whether the hole has been drilled as designed or the bending (tilt angle, azimuth angle, etc.).

  In the conventional device of Patent Document 1, an azimuth meter and an inclinometer are provided in a nonmagnetic cylindrical housing. However, this inclinometer is a biaxial type, and its measurement range is from 0 to 90 weakness (horizontal) in the vertical angle. In addition, the compass is composed of an electronic magnetic compass, and this electronic magnetic compass has a configuration in which a biaxial fluxgate compass is placed in the gimbal and the compass is always kept horizontal even when the tilt angle increases. It has become. Due to the configuration of the azimuth meter using the electronic magnetic compass, it is difficult to reduce the size of the measuring device of Patent Document 1, and there are the following problems.

(1) For example, when trying to use for the measurement of hole bending in the double pipe double packer method, the diameter of the other party to be inserted must be 60 mm or more. ) Cannot be inserted into the casing, and must be inserted into the casing for measurement. For this reason, during the hole bending measurement operation, the casing could not be pulled out, and it was necessary to wait for the boring machine after excavation for about 40 to 60 minutes. This meant that there was a period of about 40-60 minutes for each drilling where the casing and boring machine could not be used for other drilling, which was very uneconomical. . It is impractical to prepare expensive casings for all holes.

(2) In addition, the geomagnetic sensor type biaxial measuring device has a measurement limit for oblique holes, such as being unable to measure upward bore holes, and some bore holes cannot be measured with poor oblique accuracy. Moreover, since an annular permalloy was used for the coil core, the sensitivity was not sufficient, and it was not suitable for measurement in the triaxial direction.

  The present invention has been made in view of the above-mentioned problems, and its object is to provide a small-diameter and high-precision hole bending measuring device that can be used by inserting into an injection outer tube or an upward boring hole, and a chemical solution using the device. It is to provide an injection method.

  In order to achieve the above object, in the invention according to claim 1, the hole bending measuring device is configured as follows. That is, a hole bending measuring device that is inserted into a hole and measures the bending of the hole is provided in a cylindrical container formed of a non-magnetic material in the X, Y, and Z directions orthogonal to each other. It receives signals from a triaxial magnetic sensor that measures the strength of geomagnetism, a triaxial acceleration sensor that measures acceleration in the triaxial directions of X, Y, and Z, and the triaxial magnetic sensor and the triaxial acceleration sensor. And a signal processing circuit unit for calculating the azimuth angle and the inclination angle of the drilling hole, a power supply circuit unit, and a signal transmission circuit unit, and the three-axis magnetic sensor is provided inside the cylindrical container body. A holder made of a non-magnetic material that closely fits to the periphery, and a single unit of magnetic sensor in each direction fitted and fixed in three holding holes formed orthogonal to the holder, Each magnetic sensor is made up of a coil wound around a rod-shaped core material, Characterized in that it is surrounded fixed by the system material.

  Moreover, in the invention which concerns on Claim 2, a chemical | medical solution injection | pouring method is comprised as follows. That is, after drilling the ground and inserting the casing to a predetermined depth, the casing is filled with seal grout, and an outer injection pipe is installed, the casing is pulled out, and then injected into the outer injection pipe with a packer. In a chemical injection method for improving the ground by injecting a chemical solution by erection of an inner tube, the hole bending measuring device according to claim 1 is inserted into the outer injection tube after the outer injection tube is installed and the casing is pulled out. Then, the hole bending is measured, and after filling, the injection inner tube with a packer is installed in the outer injection tube, and the injection adjustment of the chemical solution is performed according to the measured hole bending measurement value.

According to the present invention, the following excellent effects can be obtained.
According to the hole bending measuring apparatus according to the first aspect of the present invention, a triaxial magnetic sensor is provided instead of the conventional azimuth meter. And, as the structure of the magnetic sensor alone provided to be oriented in each direction of the three-axis magnetic sensor, the outer periphery of the coiled core rod is surrounded and fixed by the silicon-based material. A small-diameter unit tool device capable of measuring the hole bending with high accuracy can be configured by inserting the tube into the injection outer tube in the pipe double packer method. In short, measurement can be performed without using a boring hole drilling device. In addition, the measurement accuracy for oblique measurement is improved, and measurement is possible even with an upward bored hole.
Furthermore, since the X, Y, and Z axis arrangements are not shifted by vibration, each magnetic sensor is inserted into the holder's holding hole and surrounded by a silicon-based material, so that large vibrations are transmitted during insertion. In addition, the strict X, Y, and Z axis arrangement can be correctly maintained, and vibration can be buffered by the silicon-based material.

  According to the chemical injection method according to the invention of claim 2, after the injection outer pipe is installed and the casing is pulled out, the hole bending measuring device of claim 1 is inserted into the injection outer pipe to measure the hole bending. After that, the chemical solution is injected into the outer injection tube by, for example, installing a packer inner injection tube with a double packer attached to the tip. In other words, the hole bending measurement operation is performed on the injection outer tube from which the casing has already been extracted, and therefore the casing and the boring machine can be used for other drilling. Therefore, during the hole bending measurement operation (40 to 60 minutes), it is not necessary to wait for the boring machine after excavation as it is, and the chemical injection method can be implemented with high efficiency.

  Hereinafter, the present invention will be described based on the illustrated embodiments.

  FIG. 1 shows a configuration of a hole bending measuring device 5 according to this embodiment. This hole bending measuring device 5 includes a non-magnetic cylindrical container 10, in order from the tip side, a three-axis magnetic sensor (azimuth meter) 11, a magnetic sensor and acceleration sensor signal processing circuit unit 12, and a three-axis acceleration sensor. (Inclinometer) 13 has a unit tool structure in which a power supply circuit and a signal transmission circuit section 14 are provided.

  Specifically, the non-magnetic cylindrical container 10 is a synthetic resin cylindrical container having a diameter of 37 mm and a length of 700 mm. The three-axis magnetic sensor (azimuth meter) 11 provided on the lower end side inside the container 10 has geomagnetic strength in the three-axis directions of the X-axis along the container center axis, the Y-axis perpendicular to it, and the Z-axis. The magnetic sensor units 11a, 11b, and 11c having excellent directivity characteristics in the uniaxial direction are arranged in three axes so as to be directed in the X, Y, and Z axis directions, respectively. Similarly, the triaxial acceleration sensor 13 provided in the middle of the container 10 has a structure in which the acceleration sensors 13a, 13b, and 13c are arranged triaxially so as to be directed in the triaxial directions of X, Y, and Z. .

  As for the triaxial acceleration sensor (tilt meter) 13, when the tool is tilted by arranging the triaxial acceleration sensors 13a, 13b, and 13c, the acceleration sensors 13a, 13b, and 13c of the three axes respectively convert gravity into a three-component vector. From this, the inclination angle from the perpendicular of the cylindrical container 10 can be calculated.

  As for the three-axis magnetic sensor (azimuth meter) 11, similarly, the three-component vector can be measured by measuring the geomagnetic component in the configuration in which the magnetic sensors 11 a, 11 b and 11 c are arranged in three axes. Since it is a triaxial measurement, 0 to 360 degrees can be measured. From the vector component relationship of both the triaxial magnetic sensor 11 and the triaxial acceleration sensor 13 described above, the orientation (angle from magnetic north) of the inclined cylindrical container 10 can be calculated.

Here, each component output of the acceleration sensor is g (x, y, z), each component output of the magnetic sensor is H (x, y, z), and each component output of the magnetic sensor projected on the reference horizontal plane is H (x ₁ , y ₁ , z ₁ ), the inclination angle θincl and the azimuth angle θazm as shown in FIG. 2 can be expressed by the following equations.
θincl = Atan (g _y ² + g _z ² ) ^1/2 / g _x

θazm = Atan (−H _y1 / H _x1 )
= Atan {(H _z · g _y −H _y · g _z ) · g / H · (g _y ² + g _z ² ) −H _y · g _x · y _y −H _z · g _x · g _z )}

Also,
g ² = g _x ² + g _y ² + g _z ² = 1.0
And therefore g _x = ± (1-g _y ² -g _z ² ) ^1/2
It becomes.

  That is, in the hole bending measuring device of the present embodiment, the compass is not constituted by an electronic magnetic compass as in the prior art, and the three-axis magnetic sensor 11 and the three-axis acceleration sensor 13 and the output arithmetic processing circuit (magnetic) It differs greatly from the conventional one in that it is constituted by a signal processing circuit unit 12) of the sensor and the acceleration sensor.

  By the way, in order to reduce the size and improve the sensitivity of the triaxial magnetic sensor 11, as shown in FIGS. 3A and 3B, the coil core material 111 of each single magnetic sensor 11a, 11b, 11c is used. For this, a rod-shaped super permalloy (permeability is 100 times that of permalloy) is used, and a coil 112 is wound around this to form a magnetometer. Further, since vibration may be applied when the hole bending measuring device is inserted into the hole, the individual magnetic sensors 11a, 11b, and 11c are provided with a cushioning material made of a silicon-based material as a countermeasure against the vibration. It is surrounded by 113 and hardened in a cylindrical shape, and is accommodated in an aluminum holder 114 and fixedly held.

  The aluminum holder 114 has a cylindrical shape, and is formed with three holding holes 115 having a circular cross section perpendicular to each other along the three axial directions. Each of the holding holes 115 has a single magnetic sensor 11a, 11b, 11c is fitted and mounted. In addition, the outer diameter of the holder 114 is adjusted to the inner diameter of the cylindrical container 10, and the holder 114 is fitted and mounted in the cylindrical container 10 without rattling. Therefore, the three-axis magnetic sensor 11 that is small in size and capable of capturing the geomagnetism of the X, Y, and Z axes sensitively can be made as small as possible.

  The magnetometers (magnetic sensors 11a, 11b, 11c) of the three-axis magnetic sensor 11 configured in a small size as described above must be strictly fixed to the three axes of the X, Y, and Z axes. The error is required to be 1/100 or less. Reference numeral 15 denotes a Z-axis alignment pin.

  The hole bending measuring device 5 of the present embodiment measures displacement by being lowered in the hole with a winch or a rod when measuring the hole bending. It has a small outer diameter of 37 mm and a minimum measurement diameter of 40 mm. If the hole has a diameter of 40 mm or more, it can be inserted to measure the bending of the hole.

  Here, in the measuring instrument by the biaxial measurement that can measure the bending of a slant hole or horizontal hole of vertical ± 5 ° or more, the size thereof is large, and it can be inserted unless it is a hole of about 10 cm or more. Therefore, it was not possible to measure the bending of a small-diameter hole whose diameter is less than 10 cm. For example, when trying to measure the drilling accuracy of a chemical injection hole by oblique to horizontal construction, since the hole bending measuring instrument is large, it is only through the casing immediately after the casing drilling of about φ10 cm in diameter is performed. It could not be measured. Therefore, until the measurement of the bending of the hole is completed, the casing cannot be diverted, and the progress of the casing drilling is delayed. In addition, synergistically with the delay in the casing drilling, the conventional measuring instrument uses a gyro, so it is necessary to warm up the oil holding the gyro at the time of measurement. Therefore, it took time to measure, and the number of measurements per day was limited, so that only a very small number could be measured.

  However, the above-described hole bending measuring apparatus according to the present embodiment has an outer diameter of 37 mm, and is inserted into a small-diameter hole that has been impossible in the past, such as in an injection outer pipe (inner diameter 40 mm) used in the double packer method. Thus, it becomes possible to measure the bending of the hole. Therefore, there is no hindrance to the measurement of the bending of the hole even after the outer pipe is installed and the casing is pulled out. It can be carried out. In addition, the hole bending measuring device of the present embodiment does not require warming up when performing the measurement, can reduce the measurement time as much as possible, and can measure the bending of a large number of holes.

  Hereinafter, the enforcement example of the double pipe double packer construction method using the said hole bending measuring apparatus is demonstrated using FIG.4, FIG.5 and FIG.7.

  First, as shown in FIG. 7A, the ground is drilled to a predetermined depth by a drilling machine (rotary boring machine or rotary percussion) 4. This hole is made by the casing 1 (FIG. 4) for the purpose of protecting the hole wall and installing an injection outer pipe to be described later (casing hole drilling process: see FIG. 5 (a)).

  Next, as shown in FIG. 7C, the casing 1 is filled with a seal grout 3 (FIG. 4). That is, the muddy water is changed to the sealing liquid (CB liquid) to fill the hole (replacement process of muddy water with the sealing liquid: see FIG. 5C). The seal grout 3 is filled by inserting a flexible pipe to the bottom of the hole.

  After that, as shown in FIG. 7 (d), the outer injection pipe 2 (FIG. 4) whose end is closed with a cap is installed in the casing 1, and the casing 1 is pulled out (the casing after the injection outer pipe is installed). Drawing step: see FIG. 5 (d)).

  The above steps (a) to (d) are repeated, and all the holes are sequentially drilled (see FIGS. 5 (e) and 7 (e)). At this time, the casing 1 pulled out in the step (d) is diverted to an opening operation at another location.

  Next, the above-mentioned hole bending measuring device 5 having a diameter of 37 mm in FIG. 1 is lowered with a winch or a rod and inserted into the injection outer tube 2 having an inner diameter of 40 mm as shown in FIG. 4, and the winch is stopped every 2 m. The bending (azimuth angle and inclination angle) is measured (hole bending measurement step: see FIGS. 5B-2 and 7B-2). Regarding the performance of the inclinometer, the tilt angle accuracy is ± 0.1, and the tilt angle measurement range is 0 to 90 degrees or more. Regarding the performance of the compass, the azimuth angle accuracy is ± 0.25 degrees, and the measurement direction is omnidirectional. is there.

  Next, as shown in FIG. 5 (f), an injection inner tube (injection hose) with a packer having a double packer attached to the tip is built into the injection outer tube 2 to form a double tube. Then, move the injection inner tube in the axial direction so that the injection hole of the injection inner tube coincides with the deepest injection hole of the injection outer tube, and adjust the injection of the chemical according to the measured hole bending measurement value. The chemical liquid is pumped and the chemical liquid 6 is injected into the ground from the injection hole as shown in FIG. 2 (injection implementation process: see FIG. 5 (f)).

  Next, by moving the injection inner pipe upward, the injection hole is aligned with the injection hole directly above, and the chemical solution is injected from the injection hole into the ground (see FIG. 7G). This process is sequentially performed up to the uppermost injection hole, and a chemical solution is injected into the ground from each injection hole (see FIG. 7 (h)).

  Since the outer diameter of the hole bending measuring device 5 is reduced to 37 mm and can be inserted into the outer injection pipe, there is no restriction that it must be measured when drilling a large diameter casing, and the outer injection pipe (inner diameter 40 m) is built. Later, it becomes possible to measure the hole bending through the injection outer tube. Therefore, it is not necessary to stop the construction of the chemical solution injection work on the way. In addition, it is not necessary to warm up each hole to be measured, and the measurement time is shortened as much as possible. The number that can be measured can be greatly increased. Furthermore, since the casing can be transferred to the next planned drilling location and diverted immediately after the casing drilling is completed, the drilling work can be carried out efficiently and the construction period can be greatly shortened.

It is a figure which shows schematic structure of the hole bending measuring apparatus of this invention. It is a figure explaining inclination-angle (theta) incl and azimuth-angle (theta) azm of a hole bending measuring apparatus. It is a perspective view which shows schematic structure of the triaxial magnetic sensor shown in FIG. 1, (a) shows the single-piece | unit magnetic sensor provided oriented in each axial direction, (b) hold | maintains the single-piece | unit magnetic sensor. Indicates the holder to play. It is the schematic which shows the form which utilized the hole bending measuring apparatus of this invention for the double pipe double packer construction method. It is the figure which showed the construction procedure of the double pipe double packer construction method of this invention. The construction procedure of the conventional double pipe double packer method is shown. It is the figure which showed the construction procedure of the double pipe double packer construction method of this invention with the construction procedure of the conventional double pipe double packer construction method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Casing 2 Outer pipe | tube 3 Seal grout 4 Drilling machine 5 Hole bending measuring device 6 Chemical solution 10 Nonmagnetic cylindrical container 11 Triaxial magnetic sensor 11a, 11b, 11c Magnetic sensor (single unit)
111 Coil core material 112 Coil 113 Cushion material made of silicon 114 Aluminum holder 115 Holding hole 12 Signal processing circuit unit 13 Triaxial acceleration sensor 13a, 13b, 13c Acceleration sensor (single unit)
14 Power supply circuit and signal transmission circuit section 15 Z-axis alignment pin

Claims (2)

A hole bending measuring device that is inserted into a hole and measures the bending of the hole,
A three-axis magnetic sensor that measures the geomagnetic strength in the three-axis directions of X, Y, and Z orthogonal to each other in a cylindrical container formed of a non-magnetic material, and the same three-axis directions of X, Y, and Z A three-axis acceleration sensor that measures the acceleration of the drill, a signal processing circuit unit that receives signals from the three-axis magnetic sensor and the three-axis acceleration sensor, and calculates an azimuth angle and an inclination angle of the drilling hole; The signal transmission circuit section is installed internally,
The three-axis magnetic sensor is fitted and mounted in a holder made of a non-magnetic material that fits closely to the inner periphery of the cylindrical container body, and in three holding holes formed orthogonal to the holder. And a single magnetic sensor in each direction,
A device for measuring a bending of a hole, characterized in that a single unit of each magnetic sensor has a coil wound around a rod-shaped core member and its periphery is surrounded and fixed with a silicon-based material. After drilling the ground and inserting the casing to the specified depth, the casing is filled with seal grout, the outer injection pipe is installed, the casing is pulled out, and then the inner injection pipe with packer is inserted into the outer injection pipe In the chemical solution injection method to improve the ground by injecting chemical solution by installing
After the outer injection pipe is installed and the casing is pulled out, the hole bending measuring device according to claim 1 is inserted into the injection outer pipe to measure the hole bending. A chemical injection method characterized in that an inner pipe is built and the injection adjustment of the chemical is performed according to the measured measured value of the bending of the hole.

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