JP2961144B2 - Multi-axis underground displacement meter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multiaxial underground displacement meter and, more particularly, to a relative position measurement between a plurality of measuring points provided in a well bore formed in a ground and a measuring section provided in a hole. The present invention relates to a multiaxial underground displacement meter that measures displacement of the ground by detecting a change by a measurement unit.

[0002]

2. Description of the Related Art Conventionally, in the field of civil engineering and mining, or in the field of geophysics, in order to properly evaluate the behavior of rock or the crust, or in the field of soil engineering, a soil behavior monitoring monitor. In order to obtain the material of
Ground displacement measurement is being performed. As a method of measuring the displacement of the ground, a method using an extensometer is generally employed. In other words, this method establishes a fixed measuring point in a borehole drilled in rock or other ground,
The change of the relative position along the hole axis direction between the fixed measuring point and the measuring point provided at the hole is transmitted to the hole via a wire or rod extending from the fixed measuring point, and this is transmitted to the hole. It is to be detected and measured by a displacement meter such as a fixed differential transformer.

[0003] In this method, the fixed measuring points in the well are fixed to the well using a mortar, an adhesive, or the like. Point measurement becomes possible, and the displacement of the ground can be measured with high accuracy.

[0004]

However, measuring the displacements of a plurality of fixed measuring points provided in one borehole by the above-mentioned extensometer has the following problems.

That is, according to the conventional method, each displacement of a plurality of fixed measuring points is measured by connecting a displacement meter to each wire or rod connected to each fixed measuring point. Since fixed stations cannot be moved because they are fixed inside the borehole, systematic multi-point measurement of the entire ground is simple, economical and efficient, for example, in ground deformation measurement for tunnel support design and construction evaluation. For example, when it is necessary to perform high-precision measurement, there is a problem that such a demand cannot be sufficiently satisfied.

Accordingly, the present invention has been made in view of such a conventional problem, and it is possible to easily, economically and efficiently perform systematic multi-point measurement of the entire ground. It is an object of the present invention to provide a multiaxial underground displacement meter capable of measuring displacements of a plurality of fixed measuring points in a well well with high accuracy.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above object, and the gist of the present invention is to provide a measuring point provided at a plurality of measuring points provided in a well bore formed in a ground. A multi-axial underground displacement meter that measures the displacement of the ground by detecting the change in the relative position between the measuring point via a linear member that is connected to each measuring point and extends to the hole mouth. Fixing means for detachably fixing each measuring point portion in the borehole by moving each measuring point portion in the radial direction of the well by means of a telescopic means such as a hydraulic cylinder or a spring; and a shaft of the well hole. And a holding hole for inserting and holding each linear member extending from the measuring point located forward of the measuring point without interfering with each other. In the displacement meter.

In the multiaxial underground displacement meter according to the present invention, the measuring section provided at the hole may measure a distance between a rear end face of a plurality of linear members extending to the hole and a laser beam, an electromagnetic wave or the like. It is preferable to have a non-contact distance measuring means for measuring via a.

Further, in the multiaxial underground displacement meter of the present invention, the rear end faces of the plurality of linear members extending to the hole are arranged on one circumference at the hole, and are arranged on the circumference. The non-contact distance measuring means is arranged in opposition to the rear end face, and the laser light, the electromagnetic wave, and the like are rotated and scanned along the circumference to thereby displace the plurality of rear end faces to the non-contact distance measuring means. Is preferably measured continuously.

Further, in the multiaxial underground displacement meter according to the present invention, a surface member capable of adjusting the expansion and contraction in the axial direction of the linear member may be attached to each rear end surface of the plurality of linear members extending to the hole. it can.

The multiaxial underground displacement meter according to the present invention further comprises a CPU for controlling rotation / measurement and data recording of the non-contact distance measuring means, a displacement signal amplifier with power control for laser light, electromagnetic waves, etc. It is also possible to provide a data logger integrating the converter and the data recording memory.

[0012]

According to the multiaxial underground displacement meter of the present invention, the plurality of measuring points installed in the borehole have detachable fixing means and are connected to the measuring points and extend to the hole. The linear member is held in each holding hole of the subsequent measuring point portion and extends to the hole without any interference with each other. Therefore, by releasing the fixing means and moving forward and backward through the linear member, each measuring point can be easily re-installed at an appropriate place, and the displacement of the ground after fixing each measuring point. , The displacements of the plurality of measuring points can be accurately transmitted to the hole.

Further, the displacement can be measured more quickly by measuring the distance between the linear member extending to the hole and each rear end face by using a non-contact distance measuring means using laser light, electromagnetic waves or the like. .

Further, each of the rear end faces of the plurality of linear members extending to the hole is disposed on one circumference at the hole, and the rear end face is opposed to each of the rear end faces disposed on the circumference. If a contact distance measuring means is arranged and the laser beam, electromagnetic wave or the like is rotated and scanned along the circumference, displacement of a plurality of rear end faces can be easily and continuously measured by one measuring means.

Further, if a surface member that can be adjusted in the axial direction of the linear member is attached to the rear end surface of the linear member extending to the hole, the displacement of the measuring point accompanying the displacement of the ground is large. Therefore, even when the measurement range is exceeded by the contact distance measuring means, the displacement can be continuously measured by adjusting the position of the measurement surface.

The multiaxial underground displacement meter of the present invention further includes a CPU for controlling rotation / measurement and data recording of the non-contact distance measuring means, a displacement signal amplifier with power control for laser light, electromagnetic waves, etc. By connecting the converter and the data recording memory to an integrated data logger, long-term automatic measurement of ground displacement becomes possible.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic cross-sectional view showing a situation where the ground displacement is measured using the multiaxial underground displacement meter according to this embodiment. That is, the multiaxial underground displacement meter 10 according to this embodiment mainly includes a measurement point unit 13 installed at a plurality of locations in a well 12 formed by drilling a rock 11.
High rigid rod 1 as a linear member connected to each measuring point 13 and extending along hole 12 to hole 14
5 and a measuring unit 16 disposed at the hole facing the end face of the high-rigidity rod 15 protruding from the hole 14.

As shown in the enlarged view of FIG. 2, each measuring point 13 has a cylindrical measuring point main body 17 having a cross section that can be inserted into the borehole 12 and a crossing of the measuring point main body 17. Fixed cylinder 18 which is provided at
It consists of: And the fixed cylinder 18
A spring 20 provided in the first compartment 19 urges the fixing pin 30 at the distal end so as to protrude radially outward, and a second compartment 22 through a pressure supply line 21.
The fixing pin 30 is retracted radially inward against the urging force of the spring 20 by the hydraulic pressure fed to the spring 20. That is, the fixed pin 30 provided at the tip of the fixed cylinder 18
Controls the hydraulic pressure from the pressure supply line 21 to slide and retreat as appropriate in the radial direction of the well 12, whereby the measuring points 13 can be fixed to the well 12 and released arbitrarily. Can be.

Each measuring point 13 has a measuring point main body 17.
A high-rigidity rod 15 is attached so as to be connected to the rear end portion. The high-rigidity rods 15 are preferably made of a material such as carbon steel, nickel steel or the like which is less likely to expand and contract due to a temperature difference.
Is extended to the hole 14 while being inserted and held in the holding hole that opens in the axial direction of the well 12. That is, the measuring unit main body 17 of each measuring unit 13 is held at a position corresponding to the mounting position of the high-rigidity rod 15 on the front measuring unit 13 in a circumferential shape along the outer edge thereof. Since the holes are formed, the high-rigidity rods 15 interfere with each other by sequentially inserting the high-rigidity rods into the holding holes corresponding to the mounting positions of the measuring section 13 located rearward. It extends to the hole 14 in parallel and orderly without doing. In FIGS. 1 and 2, reference numeral 23 denotes a guide member which has a holding hole that opens in the axial direction of the well 12, similarly to the measuring section 13, and in which the installation interval between the adjacent measuring sections 13 is large. The high-rigidity rod 15 is held together with the measuring portion 13 by the holding holes of the guide member 23. The holding holes of the guide member 23 are used as the holding holes of the measuring portion 13. It can also be used.

Then, as shown in the enlarged view of FIG. 3, the measuring section provided at the opening of the well 12 has
A laser displacement meter 24 is provided as non-contact distance measuring means, which is disposed to face a rear end surface of the high rigid rod 15 protruding from the hole 14. The laser displacement meter 24 is of a known type, and has a support frame 25 fixed to the rock wall surface at the hole opening.
Thus, the irradiation laser 29 is rotatably driven by a motor 26 while being opposed to the end face of the high-rigidity rod 15 so that the irradiation laser 29 is moved to the rear end faces of the plurality of high-rigidity rods 15 arranged on one circumference. Scan along the axis. That is, since each of the high-rigidity rods 15 is inserted and held in each of the holding holes circumferentially arranged along the outer edge of the measuring point portion 13 or the guide member 23 and extends to the hole 14, The end face of the high-rigidity rod 15 is arranged neatly on one circumference as shown in FIG. Therefore,
Irradiation laser 2 from laser displacement meter 24 along this circumference
By rotating and scanning 9 at a predetermined cycle, the displacement of the plurality of measuring points 13, that is, the displacement of the end face of each high-rigidity rod 15, is continuously measured at multiple points.

A surface member 27 is attached to the rear end of each high-rigidity rod 15. The surface member 27 forms a rear end surface of the high-rigidity rod 15 as a measurement surface, and includes, for example, a male screw provided at a rear end portion of the high-rigidity rod 15 and a female screw provided on an inner peripheral surface of the surface member 27. In addition, the high rigid rod 15 has a configuration capable of adjusting the expansion and contraction in the axial direction.

The laser displacement meter 24 includes a CPU for controlling rotation / measurement and data recording of the laser displacement meter 24,
It is connected to a data logger 28 in which a displacement signal amplifier with power control for laser light, electromagnetic waves, etc., an AD converter and a data recording memory are integrated.

The multiaxial underground displacement meter 10 of this embodiment
According to the above, each of the measuring points 13 releases the fixing to the well 12 by the fixing cylinder 18 and the high rigid rod 15
And can be easily re-installed at an arbitrary position in the well 12. The high-rigidity rod 15 connected to each of the measuring points 13 is connected to the following measuring points 1.
3 or the guide member 23 is inserted into and held by each holding hole, and extends to the hole 14 without any interference, so that the displacement amount along the hole axis of the measuring point portion 13 accompanying the displacement of the ground can be accurately determined. It is transmitted to the hole 14.

Further, the displacement of the rear end face of the high-rigidity rod 15 can be quickly measured using laser light, and the laser light is rotated and scanned along one circumference on which each rear end face is arranged. Thus, the displacement of the plurality of measuring points 13 can be easily and continuously measured by one laser displacement meter 24.

Further, since the rear end surface of the high-rigidity rod 15 is constituted by the surface member 27 which can be adjusted to expand and contract in the axial direction of the high-rigidity rod 15, the displacement of the rear end surface increases and the rotation scanning of the irradiation laser 29 is performed. In this case, the displacement can be continuously measured by adjusting the position of the rear end surface even if the measurement range of the laser displacement meter 24 is exceeded.

The displacement of the rear end face of the high-rigidity rod 15 is output as a voltage analog signal by a displacement signal amplifier with laser power control in a data logger 28 connected to the laser displacement meter 24, and the voltage is converted via an AD converter. It is converted into a digital signal and taken into the CPU. Also,
In order to detect the displacement of the station in the rock as a relative change from the reference point of the hole 2, after initial value correction by the CPU, the time-series data file of each station is recorded in the data recording memory. The CPU in the data logger 28 also incorporates measurement interval control, rotation control of the laser displacement meter, and data file input / output control to realize long-term automatic measurement in the field. Therefore, it is possible to obtain a monitor for predicting a phenomenon leading to destruction or collapse of a rock wall surface or a slope.

[0027]

As described above in detail, according to the multiaxial underground displacement meter of the present invention, a plurality of measuring points installed in a well bored in the ground are easily moved and relocated to appropriate places. The linear member that can be installed, and is connected to each measuring point and extends to the hole, is inserted and held by the holding hole, and extends to the hole without any interference, so that each linear member can be installed. Since the displacement can be accurately transmitted to the hole, the systematic multi-point measurement of the entire ground can be performed easily, economically and efficiently, and the displacement of multiple measurement points within one well can be measured. It can measure with high accuracy.

Further, the displacement can be measured more quickly by measuring the distance between the linear member extending to the hole and each rear end face using a non-contact distance measuring means using a laser beam, an electromagnetic wave or the like. .

Further, if the rear end faces of the plurality of linear members are arranged on one circumference at the hole portion, and the laser beam, the electromagnetic wave or the like is scanned along the circumference, one measuring means can be obtained. This makes it possible to easily and continuously measure displacements of a plurality of rear end faces.

Furthermore, if a surface member that can be adjusted in the axial direction of the linear member is attached to the rear end surface of the linear member,
Even when the displacement amount of the measuring point portion exceeds the measurement range of the contact distance measuring means, the displacement can be continuously measured by adjusting the position of the measurement surface.

The multiaxial underground displacement meter according to the present invention further includes a CPU for controlling rotation / measurement and data recording of the non-contact distance measuring means, a displacement signal amplifier with power control for laser light, electromagnetic waves, etc. By connecting the converter and the data recording memory to an integrated data logger, long-term automatic measurement of ground displacement becomes possible.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a situation where a ground displacement is measured using a multiaxial underground displacement meter according to one embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a configuration of a measuring point installed in a borehole.

FIG. 3 is a cross-sectional view illustrating a configuration of a measurement unit provided in a hole.

FIG. 4 is a side view along AA of FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Multiaxial underground displacement meter 11 Rock mass 12 Hole 13 Measurement point 14 Hole 15 High rigid rod (linear member) 16 Measurement part 18 Fixed cylinder (fixing means) 20 Spring 23 Guide member 24 Laser displacement meter (Non-contact distance) Measurement means) 27 face members 28 data logger

──────────────────────────────────────────────────続 き Continuing on the front page Examiner Yoko Watanabe (56) References JP-A-49-96759 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) G01C 7/06 E21B 47 / 00,47 / 01 G01C 9/00

Claims (5)

(57) [Claims] 1. A change in the relative position between a plurality of measuring points provided in a borehole drilled in the ground and a measuring part provided in a hole is connected to each measuring point and extended to the hole. By the measuring unit through the linear member
A multiaxial underground displacement meter that measures the displacement of the ground.Each measuring point is moved in the radial direction of the well by telescopic means such as a hydraulic cylinder, a spring, etc., so that each measuring point is located in the well. Fixing means for removably fixing, and a holding means for inserting and holding each linear member extending from a measuring point located in front of the measuring point with an insertion hole opened in the axial direction of the well without interfering with each other. A multiaxial underground displacement meter characterized by having a hole. 2. A non-contact distance measuring means for measuring a distance between a rear end face of a plurality of linear members extending to the hole through a laser beam, an electromagnetic wave, or the like, wherein a measuring unit provided at the hole. The multiaxial underground displacement meter according to claim 1, wherein: 3. A rear end surface of the plurality of linear members extending to the hole is disposed on one circumference at the hole portion, and the non-contact is opposed to the rear end surface disposed on the circumference. A distance measuring means is arranged, and the displacement of a plurality of rear end faces is continuously measured by the non-contact distance measuring means by rotating and scanning the laser beam, the electromagnetic wave and the like along the circumference. 3. The multiaxial underground displacement meter according to 2. 4. The linear member extending to the hole has a rear surface attached to each of the rear end surfaces thereof, the surface member being adjustable in expansion and contraction in the axial direction of the linear member. 2. The multiaxial underground displacement meter according to 1. 5. A data logger integrating a CPU for controlling rotation / measurement and data recording of said non-contact distance measuring means, a displacement signal amplifier with power control for laser light, electromagnetic waves, etc., an AD converter and a data recording memory. The multiaxial underground displacement meter according to claim 3, further comprising: