JPH10206306A - Shearing testing device and method for ground material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shearing testing device for a ground material which can find residual strength at a large shearing deformation time of earth and whose structure and test operation are simple. SOLUTION: Both end parts of a disk-shaped or column-shaped specimen 200 are arranged in upper and lower shearing ring members 210 and 240. The lower side shearing ring member 240 is arranged on a pedestal to be driven in rotation, and the upper side shearing ring member 210 is supported in a rotation regulated condition. A cap 302 loaded by a pneumatic cylinder 314 is arranged on an upper surface of the specimen 200. In a condition where a constant load is applied to the specimen 200 by the cap 302, the lower side shearing ring member 240 is driven in rotation, and shearing displacement is forcedly caused in the specimen 200 in a shaft surrounding cross section, and torque, a vertical load, a turning angle and height displacement applied to the specimen 200 are measured.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to the determination of the shear strength of a ground material, in particular, the shear strength in a large shear deformation state, such as a state in which a soil mass surface such as a landslide surface is in contact with each other and slips. And a shear test device for a ground material.

[0002]

2. Description of the Related Art Conventionally, in order to examine the strength of the ground, a specimen taken in an undisturbed state from an original position or a specimen obtained by artificially re-depositing a ground sample that has been bounced is prepared. A one-sided shear test device that forcibly shears the center section of a specimen has been put into practical use. In addition, a triaxial compression test apparatus that compresses a solid cylindrical specimen in the axial direction of the cylindrical shape under constrained pressure has been put to practical use. In addition, in order to obtain the strength exhibited by the soil at the time of large deformation such as a landslide state, a donut-shaped specimen as shown in FIG. 9 is prepared, and a ring for forcibly shearing the central cross section of the specimen is provided. A shear test device is provided.

[0003]

By the way, the element of the soil in the ground at the original position has a strength component (adhesive force) exerted in a state where there is no vertical stress and a magnitude of the vertical stress applied to the surface. And a substantially proportional intensity component. The proportional coefficient in the latter intensity component is the internal friction angle φ. These strength components depend on the amount of shear deformation applied to the soil element, and increase with shear deformation. However, after a certain value, the strength component decreases again and eventually reaches a constant value. The strength under such a large shear deformation state is the residual strength, and corresponds to the soil strength at the time of undergoing a large deformation such as a state in which the soil mass surface slides like a landslide.

[0004] However, in the conventional single-shear test apparatus and triaxial compression test apparatus, the amount of deformation that can be applied to the specimen is limited, and therefore, the residual strength, which is the strength of the soil exerted during such a landslide state, is required. There is a problem that can not be. In addition, the conventional ring shear test device can apply large uniform shear deformation to the specimen and determine the residual strength of the soil.However, when using an undisturbed in-situ sample, a donut It is difficult to prepare a test specimen in a shape of a letter, and the structure of the test apparatus and the test operation are complicated.

In view of the above circumstances, an object of the present invention is to provide a ground material shear test apparatus which can determine the residual strength of soil during large shear deformation and which has a simple structure and simple test operation. It is in.

[0006]

In order to achieve the above object, the present invention comprises an apparatus frame, and a first holding mechanism and a second holding mechanism supported on the apparatus frame so as to face each other. The first holding mechanism and the second holding mechanism each have a concave portion in an opposing portion thereof, and the concave portion of the first holding mechanism and the concave portion of the second holding mechanism form a substantially solid disk-shaped ground. A substantially disk-shaped accommodation space corresponding to the shape of the specimen for accommodating the specimen of the material is defined, and the substantially solid disk-shaped specimen is accommodated in the accommodation space. A loading mechanism for applying a compressive load in the axial direction of the shaft; and a rotation drive mechanism for relatively rotating the first holding mechanism and the second holding mechanism. The rotary drive in a state where a compressive stress is applied from a mechanism; By rotating the first holding mechanism and the second holding mechanism relative to each other, the specimen can be sheared on a shear plane substantially perpendicular to the axis of the substantially solid disk. Load measuring means for measuring a compressive load applied to the specimen from the load mechanism described above,
And a torque measuring means for measuring a torque applied to the specimen when the specimen is sheared.

Further, the present invention is characterized in that the first holding mechanism and the second holding mechanism are arranged vertically so that the axial direction of the substantially solid disk shape of the specimen is the vertical direction. Features. Further, in the present invention, the first holding mechanism is substantially non-rotatably supported, and a compressive load is applied from the loading mechanism to the first holding mechanism, and the second holding mechanism is rotatable. It is supported substantially immovably in the vertical direction, and the rotation drive mechanism rotates the second holding mechanism.

Further, according to the present invention, the first holding mechanism includes a ring member defining an outer peripheral wall of the recess of the first holding mechanism and supported substantially non-rotatably, and a ring member of the recess of the first holding mechanism. A loading member defining a bottom wall, being substantially non-rotatably supported and receiving a compressive load from the loading mechanism, wherein the second holding mechanism is configured to remove the outer peripheral wall and the bottom wall of the concave portion of the second holding mechanism. It has a bottomed container defined and supported by a rotation support mechanism. Further, according to the present invention, the load mechanism has a piston / cylinder mechanism for generating a load, and a load transmission mechanism for transmitting the load generated by the piston / cylinder mechanism to the load member, wherein the load transmission mechanism is And a spline shaft supported on the apparatus frame so as to be slidable and non-rotatable in a vertical direction. The present invention also provides
The loading member of the first holding mechanism is provided with a friction member for transmitting a shear stress between the loading member and the specimen, and the bottom wall of the concave portion of the second holding mechanism is provided with the bottom wall. It is characterized in that a friction member for transmitting shear stress between the sample and the sample is provided.

[0009] The present invention also provides a load transmitting device, wherein the load measuring means is interposed between the spline shaft and the piston / cylinder mechanism in a load transmitting path of the load transmitting mechanism, and the load measuring means is provided between the spline shaft and the load member. It is characterized in that the torque measuring means is interposed therebetween. The present invention also provides a deformation amount measuring means for measuring an amount of deformation of the specimen in the axial direction, a rotation amount measuring means for measuring a relative rotation amount between the first holding mechanism and the second holding mechanism, It is characterized by having. Further, the present invention is characterized in that a container for storing a liquid impregnating the specimen held by the first holding mechanism and the second holding mechanism is provided. Further, the present invention is characterized in that it has an adjusting mechanism for adjusting a distance between the first holding mechanism and the second holding mechanism.

[0010] The present invention also provides a specimen of a substantially solid disk-shaped ground material, a first holding mechanism and a second holding mechanism defining a substantially disk-shaped accommodating space corresponding to the shape of the specimen. The first holding mechanism and the second holding mechanism are relatively held in a state where a compressive load is applied to the specimen held in the housing space in the axial direction of the substantially solid disk shape held by the holding space. By rotating the specimen, the specimen is sheared on a shear plane substantially perpendicular to the axis of the substantially solid disk, and the specimen is joined to the specimen in a sheared state. It is characterized in that the compressive load and the torque are measured, and the residual strength of the specimen is obtained from the measured value of the compressed load and the measured value of the torque. Further, the present invention is characterized in that a value obtained by halving a shear displacement in a direction around an axis at an outer peripheral portion of the specimen is used as an average shear displacement of the specimen. Further, the present invention is characterized in that the relative rotation amount between the first holding mechanism and the second holding mechanism is sufficiently large so that the shear stress applied to the shear surface of the specimen can be regarded as substantially uniform. I do.

In the shear test apparatus or method for a ground material according to the present invention, in a state where both ends of a substantially solid disk-shaped specimen are held by first and second holding members, the axial direction of the specimen is A load is applied by a loading mechanism to the consolidation.
After the consolidation, while applying a constant load by the loading mechanism, a torque is applied to the specimen by the rotation drive mechanism,
The specimen is forcibly shear-deformed at the cross section around the axis of the gap between the holding members. In this case, the shear stress initially increases as the shear displacement increases, and then decreases after reaching a maximum value. This forms a shear surface in the middle of the specimen,
Further, by applying the rotational displacement continuously, a constant shear stress (residual shear stress) state in which the divided bodies of the specimens on both sides slide on each other with respect to the shear plane is obtained. Thus, by giving sufficient shear deformation, it is possible to effectively obtain the maximum strength and residual strength in a state where large shear deformation is applied to a substantially solid disk-shaped specimen.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a ground material shear test apparatus according to the present invention will be described. FIG.
1 is a cross-sectional view showing an example of the overall configuration of a ground material shear test device according to the present invention. This ground material shear test apparatus is assembled on an apparatus frame 100. The apparatus frame 100 has a plurality of columns 104 standing on a base 102 arranged at the bottom.
The middle plate portion 106 and the upper plate portion 108 are provided on the lower plate. The loading frame 11 is placed on the upper plate 108.
0 is provided. In this loading frame 110, a plurality of columns 112 are erected on the upper plate portion 108, and the columns 11
2 is provided with a mounting plate 114 at the upper end.

A test piece 200 used in the test apparatus
Is a thick solid disk, and is held by a first holding mechanism 201 and a second holding mechanism 203 supported on the apparatus frame 100. The first holding mechanism 201 and the second holding mechanism 203 are supported by the apparatus frame 100 so as to face each other, and each of the facing portions has a concave portion. Mechanism 20
With the three concave portions, a disk-shaped accommodation space corresponding to the shape of the specimen 200 for accommodating the specimen 200 is defined. Then, the first holding mechanism 201 and the second holding mechanism 2
03 is arranged vertically so that the axis direction of the substantially solid disk shape of the specimen 200 is the up and down direction. First
The holding mechanism 201 defines an outer peripheral wall of the concave portion of the first holding mechanism, and is an upper non-rotatably supported shear ring member 2.
10, the shear ring member 210 is formed in an annular shape corresponding to the outer peripheral shape of the solid disk-shaped specimen 200, and is mounted in a state of being in close contact with the outer peripheral surface on the upper end side of the specimen 200. Have been. This shear ring member 2
Reference numeral 10 denotes an annular fixed plate 214 attached to a plurality of inner supports 212 hanging down from the lower surface of the middle plate portion 106, and a shear ring member 210 is attached to the lower surface of the fixed plate 214 by screwing. The screwing structure of the shear ring member 210 is based on a fixing screw 216 and an adjusting screw 218 arranged diagonally across the specimen 200. In particular, the upper and lower shear ring members 210 and 240 are adjusted using the adjusting screw 218. Can be adjusted by tightening work from above.

On the other hand, the second holding mechanism 203 includes a lower ring member 240 formed as a bottomed container that defines an outer peripheral wall and a bottom wall of the concave portion 242 of the second holding mechanism. The member 240 receives the lower end portion of the test piece 200 in a state in which it is in close contact with a portion extending from the lower end face of the test piece 200 to the outer peripheral surface on the lower end side. Further, on the bottom surface of the concave portion 242 of the shear ring member 240, a porous stone 246, which is a friction member for transmitting shear stress, is provided. Further, the shear ring member 240
The recess 242 has an escape hole 248 for allowing gas or liquid inside the specimen 200 to escape.

The shear ring member 240 is supported by a rotation support mechanism rotatably supported on the base 102 of the apparatus frame 100. The rotation support mechanism includes a rotation shaft 252 guided by a linear motion bearing 250 provided on the base portion 102;
The rotating shaft 252 is provided integrally with the base portion 10.
2 is provided with two upper and lower plane thrust bearing portions 254, 2
And a rotating plate 258 guided rotatably by 56. A pedestal 260 as a receiving member is fixed on the rotating plate 258, and a shear ring member 240 is further fixed on the pedestal 260. . A worm wheel 262 is provided integrally between the rotating plate 258 and the pedestal 260. Rotating shaft 25
2 and the rotating plate 258 are guided by the linear motion bearing 250 and the planar thrust bearing portions 254 and 256, and rotate in a highly accurate centering state and an accurate trajectory.

The pedestal 260 is connected to a rotating plate 258 via a worm wheel 262 by a plurality of fixing screws 26.
4 fixed. The worm wheel 262 is connected to the drive motor 2 provided on the base 102.
The gear 66 meshes with a worm gear 268 that is driven to rotate. Therefore, the shear force is applied to the specimen 200 by integrally rotating the shear ring member 240 via the worm gear 268 and the worm wheel 262 by the driving force of the drive motor 266. Further, the pedestal 260 is formed in a disk table shape, and a shear ring member 240 is fixed to an upper surface thereof by a fixing screw 270.

An annular container piece 272 is fixed to the outer periphery of the upper surface of the pedestal 260. The container piece 272 extends upward from the pedestal 260 and is provided so as to surround the specimen 200, the upper shear ring member 210, and the like. The container piece 272 and the upper surface of the pedestal 260 form a water tank 274 that is a container for storing the liquid impregnating the specimen 200. By appropriately storing water or the like in the water tank 274, for example, when a test of a ground placed under water is performed, the specimen 200 can be placed in a state close to the original position. A rotation angle meter 2 is provided on the outer periphery of the pedestal 260.
80 are arranged. The rotation angle meter 280 reads the amount of rotation of the rotating body that rotates in contact with the outer peripheral portion of the pedestal 260 by using a rotary encoder or the like.
The displacement amount at the outer peripheral portion of the pedestal 260 is measured, and the rotation angle of the shear ring member 240 is calculated from the measured value.

A loading mechanism for loading a vertical load on the specimen 200 is provided above the specimen 200. The loading mechanism is connected to a cap 302 serving as a loading member that presses the upper end surface of the specimen 200. A loading rod 304 connected to the upper surface of the cap 302 and a torque meter 30 are attached to the upper end of the loading rod 304.
6, a piston rod 312 connected to the upper end of the spline shaft 308 via a pressure gauge 310, and a piston rod 312
And a pneumatic cylinder 314 that operates. The cap 302 functionally forms a part of the first holding mechanism 201, that is, defines the bottom wall of the concave portion of the first holding mechanism 201, and is connected to the spline shaft 308. Therefore, it is substantially non-rotatably supported (actually, it slightly rotates with the operation of the torque meter 306 interposed between the spline shaft 308 and the cap 302,
The amount of rotation is very small). The cap 302 has a circular end surface 316 corresponding to the shape of the upper end surface of the specimen 200, and abuts on the upper end surface of the specimen 200 with the circular end surface 316 facing the central opening of the shear ring member 210. Let me. In addition, the circular end surface portion 31 of the cap 302
6 is provided with a porous stone 318 which is a friction member for transmitting shear stress. Further, the cap 302 has an escape hole 320 for allowing the gas or liquid inside the specimen 200 to escape.

The loading rod 304 is mounted on the middle plate 10.
6 is supported by a stroke bearing 322 provided in the cap 302, and a lower end of the connecting portion 302 is provided in the cap 302.
A, and the upper end is connected to a lower connector 306B provided on the torque meter 306. In addition, loading rod 3
04 is provided with a stopper 324 located above the stroke bearing 322.
4 can be appropriately locked. The spline shaft 308 is supported by a spline bearing 326 provided on the upper plate portion 108. That is, the spline bearing 326 is attached to the upper plate portion 108 by screwing, and the spline shaft 308 is supported in a state in which movement around the axis is restricted. The upper end of the spline shaft 308 is connected to the connecting portion 3 of the pressure gauge 310.
10A, and the lower end is connected to an upper connector 306A provided on the torque meter 306.

The pneumatic cylinder 314 is provided on the upper surface of the mounting plate 114 of the loading frame 110, and the piston rod 312 is hung downward from the pneumatic cylinder 314 and connected to the pressure gauge 310. The air pressure P _O controlled by the precision regulator 330 is supplied to the rear chamber of the piston head 332 of the pneumatic cylinder 314, and the constant air pressure P _O is supplied to the front chamber of the piston head 332.
_S is given. Therefore, precision regulator 3
By controlling the air pressure to be high by 30, the piston head 332 and the piston rod 312 can be advanced to act as a downward pressing force. By controlling the air pressure to be low by the precision regulator 330, the piston head 332 and the piston rod 312 can be retracted.

The pressing force (vertical load P) of the pneumatic cylinder 314 is measured by the pressure gauge 310. The torque T acting between the spline shaft 308 and the loading rod 304 is measured by a torque meter 306. The spline shaft 308 and the upper connector 306
A and the connecting portion between the loading rod 304 and the lower connector 306B have a structure in which, for example, a key is embedded so that there is no play in the rotational direction in order to properly transmit torque. I have. Also, the lower connector 30
A displacement gauge 336 is installed between the mounting piece 334 provided on the 6B and the apparatus frame 100, and the loading rod 3
04, that is, the vertical deformation (height displacement ΔH) of the specimen 200 is measured.

According to the above configuration, the first holding mechanism 201
Is substantially non-rotatably supported, and a compressive load is applied from the loading mechanism to the first holding mechanism 201, while the second holding mechanism 203 is rotatably and substantially vertically immovably supported. Then, the drive motor 206 rotates the second holding mechanism 203. Therefore, the test specimen 200 accommodated in the accommodation space defined by the first holding mechanism 201 and the second holding mechanism 203 is subjected to the first force by the driving force of the drive motor 206 while applying a compressive stress from the loading mechanism. By rotating the holding mechanism 201 and the second holding mechanism 203 relatively, the specimen 200 can be sheared on a shear plane substantially perpendicular to the axis of the substantially solid disk.

Next, an operation procedure and an operation when a shear test is performed by the shear test apparatus having the above configuration will be described with reference to FIGS. First, the specimen 200
Is installed in a shear test apparatus as follows. First Figure 2
As shown in FIG. 7, the lower shear ring member 240 is fixed at a predetermined position. At this time, the rotation of the shear ring member 240 is held in a state of being restricted by a lock mechanism (not shown).

Next, the upper shear ring member 210 is connected to the lower shear ring member 240 by a gap adjusting screw 218.
After adjusting to keep the gap と with the appropriate interval,
The shear ring member 210 is fixed to the fixing plate 214 by the fixing screw 216. Next, as shown in FIG. 3, the solid disk-shaped specimen 200 is housed from above into the upper and lower shear ring members 210, 240, whereby the specimen 200 is moved to the first holding mechanism and the second holding mechanism. 2 is accommodated in the accommodation space defined by the holding mechanism. Then, as shown in FIG. 4, a cap 302 attached to a loading rod 304 for applying a vertical load P to the specimen 200 is provided.
Installed on the top surface of

Next, the rotation regulation of the lower shear ring member 240 is released, and a predetermined vertical load P is applied to the upper end surface of the specimen 200 by the pneumatic cylinder 314 to consolidate. Thereafter, water is poured into the water tank 274 as necessary in consideration of the state of the ground at the original position. After the consolidation, while maintaining the vertical load constant, the drive motor 2 is driven to move the lower shear ring member 240 to a predetermined displacement speed.
A rotational speed of 66 is set to apply a forcible shear displacement to the specimen 200. At this time, as shown in FIG. 5, the torque T applied to the specimen 200, the vertical load P, the rotation angle θ, and the height displacement ΔH are measured. In such a test, when shearing is started, as shown in FIG. 6, as the shear displacement increases, the shear stress increases, and decreases after reaching the maximum value. Then, a shear surface is formed between the upper and lower sides of the test piece 200, and the operation is continued until a constant shear stress (residual shear stress) slips on the shear surface.

Here, points to be considered when calculating the shear stress and the shear displacement of the specimen 200 in the shear test of the ground material of the present embodiment will be described. First, the distribution of shear displacement in the radial direction when a shear displacement due to rotation is given to the specimen 200 is not uniform, as shown in FIG.
The distribution is proportional to the radius, and the center is zero. For this reason, some assumptions are required to determine the shear displacement of the specimen 200. First, in this example, the average displacement d averaged over the entire shear plane is used as the shear displacement amount of the specimen 200. This average displacement d
Is the displacement of the outer peripheral portion of the specimen 200 if the d _0, is represented by d = d _0/2. Further, the displacement d _{0 of the} outer peripheral portion is expressed as d ₀ = (D / 2) · (π · θ / 180) using the rotation angle θ of the second holding mechanism 203 and the diameter D of the specimen 200. Is done.

Further, the shear stress depends on the amount of shear displacement, and since the relationship between shear stress and shear displacement is generally nonlinear, the distribution of shear stress in the radial direction is also generally nonlinear. To determine the shear stress τ from the measured torque T, it is necessary to know the distribution of the shear stress in the radial direction, but this is not easy to know. Therefore, in this example, the rotation angle θ of the second holding mechanism 203 is made sufficiently large by utilizing the fact that after the shear displacement becomes sufficiently large, the shear stress becomes a residual shear stress and settles to a substantially constant value. This causes a state in which the upper half and the lower half of the specimen 200 slide on the shear surface formed between them, whereby a substantially uniform area is formed over substantially the entire shear surface. The stress distribution should be as high as possible. When the shear stress has a uniform distribution over the entire shear plane, the relationship between the torque T and the shear stress τ is expressed by the following equation.

[0028]

(Equation 1)

From this equation, τ = 12 · T / (π · D ³ ) is obtained.

By the way, this assumption lacks accuracy when the shear displacement is small. Therefore, the conventional ring shear test uses a donut-shaped specimen as shown in FIG. 9 in order to reduce the influence of such non-uniform distribution of the shear displacement and the shear stress in the radial direction. However, it is difficult to prepare such a specimen, and the structure and operation of the test apparatus are complicated. Therefore, in the shear test apparatus of the present example, by providing the above assumption on the assumption that a large shear displacement is given, a shear test using a substantially solid disk-shaped specimen 200 becomes possible, and low cost is obtained. The purpose of the present invention is to provide a simple and practical shear test.

Then, the test described above was performed on the test piece 20.
The test was repeated three times or more while changing the magnitude of the vertical load P applied to 0, and as shown in FIG. 8, the maximum shear stress at each vertical stress level (σ _N1 , σ _N2 , σ _N3 ,...) The maximum strength parameter from the residual shear stress,
Find the residual strength parameter. As described above, the maximum strength and the residual strength in the large shear deformation state of the specimen 200 can be effectively obtained.

[0032]

As described above, the apparatus and method for testing the shear of a ground material according to the present invention employs a specimen having a substantially solid disk shape, and the specimen is provided with the first holding mechanism and the second holding mechanism. It is stored in the storage space defined by the holding mechanism.
Then, the first holding mechanism and the second holding mechanism are relatively rotated while a compressive load is applied to the specimen in the axial direction of the substantially solid disk, and the specimen is rotated. Is sheared by a shear plane substantially perpendicular to the axis of the substantially solid disk. Therefore, according to the ground material shear test apparatus or method of the present invention, since the shear test is performed using a substantially solid disk-shaped specimen, the preparation and preparation of the specimen are greatly simplified, and Also, the structure of the test apparatus can be made very simple, and the test operation becomes very simple. Therefore, there is an effect that a shear test capable of obtaining the residual shear strength of the ground material can be performed with a cheap equipment and a simple test method.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a configuration example of a ground material shear test apparatus according to the present invention.

2 is a cross-sectional view showing a structure of a ring shear member in the ground material shear test device shown in FIG.

FIG. 3 is a cross-sectional view showing a state in which a test piece is installed on a ring shear member in the ground material shear test apparatus shown in FIG.

FIG. 4 is a cross-sectional view showing a state where a cap is installed on a test piece installed on a ring shear member in the ground material shear test apparatus shown in FIG.

FIG. 5 is a perspective view showing the shape of a test piece used in the ground material shear test apparatus shown in FIG.

FIG. 6 is an explanatory view showing a transition of shear stress in the ground material shear test apparatus shown in FIG.

FIG. 7 is an explanatory diagram showing distribution of shear deformation and shear stress in a specimen.

FIG. 8 is an explanatory diagram showing an example of a test result in the ground material shear test device shown in FIG.

FIG. 9 is an explanatory diagram showing a distribution state of shear deformation and shear stress in a conventional donut-shaped specimen.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 device frame 110 loading frame 200 specimen 201 first holding mechanism 203 second holding mechanism 210, 240 shear ring member 242 recess 246, 318 porous stone 260 pedestal 262 worm wheel 266 drive motor 268 worm gear 274 water tank 280 tachometer 302 cap 304 Loading rod 306 Torque gauge 308 Spline shaft 310 Pressure gauge 312 Piston rod 314 Pneumatic cylinder

Claims (13)

[Claims] 1. An apparatus frame, comprising: a first holding mechanism and a second holding mechanism supported on the apparatus frame so as to face each other; wherein the first holding mechanism and the second holding mechanism are The opposing portions each have a concave portion, and the concave portion of the first holding mechanism and the concave portion of the second holding mechanism are used to accommodate a substantially solid disk-shaped ground material. A substantially disk-shaped accommodation space corresponding to the shape of the storage space is defined, and a loading mechanism for applying a compressive load to the specimen accommodated in the accommodation space in an axial direction of the substantially solid disk shape, A rotating drive mechanism for relatively rotating the first holding mechanism and the second holding mechanism, wherein the rotating drive mechanism applies a compressive stress from the loading mechanism to the specimen housed in the housing space. The first holding mechanism and the second holding mechanism are relatively By rotating the specimen, the specimen can be sheared on a shear plane substantially perpendicular to the axis of the substantially solid disk, and the compressive load applied to the specimen from the loading mechanism described in the preceding paragraph. And a torque measuring means for measuring a torque applied to the specimen when the specimen is being sheared. 2. The apparatus according to claim 1, wherein the first holding mechanism and the second holding mechanism are vertically arranged so that the axis of the substantially solid disk of the specimen is vertically oriented. The ground material shear test apparatus according to claim 1. 3. The first holding mechanism is substantially non-rotatably supported, and applies a compressive load from the loading mechanism to the first holding mechanism, wherein the second holding mechanism is rotatable. The ground material shear test apparatus according to claim 2, wherein the apparatus is substantially immovably supported in a vertical direction, and the rotation driving mechanism rotates the second holding mechanism. 4. The first holding mechanism includes a ring member defining an outer peripheral wall of a recess of the first holding mechanism and supported substantially non-rotatably, and a bottom wall of the recess of the first holding mechanism. And a loading member that is substantially non-rotatably supported and receives a compressive load from the loading mechanism, wherein the second holding mechanism defines an outer peripheral wall and a bottom wall of a concave portion of the second holding mechanism. The ground material shear test device according to claim 3, further comprising a bottomed container supported by a rotation support mechanism. 5. A load mechanism comprising: a piston / cylinder mechanism for generating a load; and a load transmission mechanism for transmitting a load generated by the piston / cylinder mechanism to a load member. 5. The ground material shear test apparatus according to claim 4, further comprising a spline shaft slidably and non-rotatably supported by said apparatus frame in a vertical direction. 6. The loading member of the first holding mechanism, wherein a friction member for transmitting a shear stress between the loading member and the specimen is provided, and a bottom wall of a concave portion of the second holding mechanism is provided on a bottom wall of the recess. The ground material shear test apparatus according to claim 5, further comprising a friction member for transmitting a shear stress between the bottom wall and the specimen. 7. A load transmission path of the load transmission mechanism,
7. The load measuring device is interposed between the spline shaft and the piston / cylinder mechanism, and the torque measuring device is interposed between the spline shaft and the load member. Ground material shear test equipment. 8. A deformation amount measuring means for measuring an amount of deformation of the specimen in the axial direction, and a rotation amount measuring means for measuring a relative rotation amount between the first holding mechanism and the second holding mechanism. The ground material shear test apparatus according to any one of claims 1 to 7, further comprising: 9. A container according to claim 1, further comprising a container for storing a liquid impregnating the test sample held by said first holding mechanism and said second holding mechanism. A shear test device for the ground material as described. 10. An apparatus according to claim 1, further comprising an adjusting mechanism for adjusting an interval between said first holding mechanism and said second holding mechanism.
A ground material shear test apparatus according to any one of claims 1 to 9. 11. A specimen of a substantially solid disk-shaped ground material is formed by a first holding mechanism and a second holding mechanism defining a substantially disk-shaped accommodation space corresponding to the shape of the specimen. Holding the test specimen accommodated in the accommodation space in a state where a compressive load is applied in the axial direction of the substantially solid disk shape to the first specimen.
By relatively rotating the holding mechanism and the second holding mechanism, the specimen is sheared on a shear plane substantially perpendicular to the axis of the substantially solid disk, and the specimen is sheared. Measuring the compressive load and the torque applied to the specimen in a state where the specimen is in a closed state, and obtaining the residual strength of the specimen from the measured value of the compressed load and the measured value of the torque. Test method. 12. The shear of ground material according to claim 11, wherein a value obtained by halving a shear displacement in a direction around an axis at an outer peripheral portion of the specimen is used as an average shear displacement of the specimen. Test method. 13. The method according to claim 1, wherein a relative rotation amount between the first holding mechanism and the second holding mechanism is sufficiently large so that a shear stress applied to a shear surface of the specimen can be regarded as substantially uniform. The method for shear testing a ground material according to claim 11 or 12, wherein the shear test is performed.