In-situ loading micro ring shear assembly

Abstract

The utility model provides an in-situ loading micro ring shear assembly, which relates to the technical field of rock and soil test equipment and comprises a pressure chamber, a plurality of micro ring shears, a plurality of micro ring shears, a plurality of micro ring shears, a plurality of micro ring shears, a plurality of micro ring shears and a plurality of micro ring shears, the lower shearing disc comprises a water-permeable disc and a lower shearing column, the water-permeable disc is mounted at the lower end of the lower shearing column, the lower end of the lower shearing column is mounted at the bottom of the sample groove, and the water-permeable disc is attached to the bottom surface of the sample groove, so that an annular space is formed between the sample groove and the lower shearing column; the upper end of the upper shearing cylinder is closed, and the upper shearing cylinder can be inserted into the annular space, so that the outer wall of the upper shearing cylinder is attached to the inner wall of the sample groove, and the inner wall of the upper shearing cylinder is attached to the outer wall of the lower shearing column. The utility model has the beneficial effects that the volume of the ring shear apparatus is greatly reduced when the device is applied to the ring shear apparatus, and conditions are provided for directly placing the ring shear apparatus into a CT scanner for CT scanning.

Description

Technical Field

[0001] The utility model relates to the technical field of geotechnical test equipment, in particular to an in-situ loading micro ring shear assembly. Background Art

[0002] The shear strength of geotechnical materials is of great significance in engineering design, disaster prevention and mitigation. The ring shear test based on a ring shear apparatus can obtain the variation law of the shear strength of materials under large deformations and measure the residual strength. At present, after a long period of development, the ring shear apparatus has become mature in terms of technology. However, the existing instrument forms cannot observe the shear evolution process and fracture behavior of geotechnical materials, and lack research on the microscopic shear failure mechanism. Therefore, it is of great significance to study the failure process of geotechnical materials at the microscopic level during the ring shear test. With the development and wide application of X-ray CT scanning technology, it has become possible to carry out the ring shear process under CT scanning. However, the current ring shear apparatus is too large to be placed inside the CT scanning device, resulting in insufficient understanding of the shear evolution process and microscopic shear fracture mechanism of geotechnical materials. Summary of the Utility Model

[0003] In view of this, in order to solve the research problem of the failure process of geotechnical materials at the microscopic level during the ring shear test, an embodiment of the utility model provides an in-situ loading micro ring shear assembly.

[0004] An embodiment of the utility model provides an in-situ loading micro ring shear assembly, including:

[0004]

[0005] A pressure chamber, which is provided with a cylindrical sample groove, and a plurality of water inlet holes are arranged on the bottom surface of the sample groove;

[0006] A lower shear disc, which includes a permeable disc and a lower shear column. The permeable disc is installed at the lower end of the lower shear column, the lower end of the lower shear column is installed at the bottom of the sample groove, and the permeable disc is in contact with the bottom surface of the sample groove, so as to form an annular space between the sample groove and the lower shear column;

[0005]

[0007] An upper shear cylinder, the upper end of which is closed. The upper shear cylinder can be inserted into the annular space, so that the outer wall of the upper shear cylinder is in contact with the inner wall of the sample groove, and the inner wall of the upper shear cylinder is in contact with the outer wall of the lower shear column.

[0008] Furthermore, it further includes a bearing base and a test bench. The test bench is rotatably arranged on the bearing base. The lower edge of the pressure chamber is fixedly connected to the test bench, and a water inlet gap is formed between the lower end of the pressure chamber and the test bench. The test bench is provided with a water injection hole, and the upper end of the water injection hole is communicated with the water inlet gap.

[0006]

[0009] Further, the water-permeable disc is arranged around the lower end of the lower shear column. A fixing column with a reduced diameter is provided below the lower end of the lower shear column and under the water-permeable disc. A fixing groove recessed downward is provided at the bottom of the sample groove. The fixing column is inserted into the fixing groove and tightly connected to the fixing groove, so that the water-permeable disc fits against the bottom surface of the sample groove.

[0010] Further, a stepped joint is formed by relative recesses on the bottom side of the pressure chamber. A receiving slot is provided at the top of the test bench. The stepped joint is inserted into the receiving slot. The bottom of the side wall of the pressure chamber is tightly connected to the upper port of the receiving slot. The water inlet hole penetrates through the stepped joint. An inlet gap is formed between the stepped joint and the receiving slot. The water injection hole is provided at the bottom of the receiving slot.

[0011] Further, a sealing ring is provided between the outer wall of the stepped joint and the inner wall of the receiving slot.

[0012] Further, a guiding column extending vertically downward is provided at the top of the upper shear cylinder. A vertically arranged guiding hole is provided on the lower shear column. The lower end of the guiding column is inserted into the guiding hole.

[0013] Further, the water-permeable disc is provided with a plurality of water-permeable holes, and a plurality of lower limiting pieces are further provided on the water-permeable disc. The lower limiting pieces are arranged along the radial direction of the water-permeable disc, and each lower limiting piece evenly divides the water-permeable disc.

[0014] Further, an upper joint is provided at the upper end of the upper shear cylinder.

[0015] Further, a plurality of upper limiting pieces extending downward are provided on the bottom surface of the upper shear cylinder.

[0016] Further, limiting teeth are provided on the bottom surface of the upper shear cylinder.

[0017] The beneficial effects brought by the technical solution provided by the embodiment of the present utility model are as follows: For an in-situ loading micro-ring shear assembly of the present utility model, the sample groove inside the pressure chamber is used to accommodate geotechnical samples, provide pore water pressure for the geotechnical samples, and can apply axial pressure to the geotechnical samples by pressing down the upper shear cylinder. Then, by rotating the pressure chamber and the lower shear disc, a circumferential shear force can be applied to the geotechnical sample, which can simulate the pore water pressure ring shear test, greatly reducing the volume of the ring shear apparatus, providing conditions for directly placing the ring shear apparatus into a CT scanner for CT scanning, so that X-ray CT scanning can be realized during the ring shear process, recording the ring shear test process at the micro scale, and obtaining spatial position information such as the movement and deformation of the geotechnical sample during the shear process, providing an important basis for studying the micro shear failure mechanism of geotechnical bodies and other materials. Description of the Drawings

[0018] Figure 1It is a schematic diagram of a in-situ loading micro-ring shear assembly of the present utility model;

[0019] Figure 2 It is an exploded view of a in-situ loading micro-ring shear assembly of the present utility model;

[0020] Figure 3 It is a schematic diagram of the upper shear cylinder in Embodiment 1;

[0021] Figure 4 It is a top view of the lower shear disc and the pressure chamber;

[0022] Figure 5 It is Figure 4 The schematic diagram of the A-A sectional view in

[0023] Figure 6 It is a schematic diagram of the pressure chamber;

[0024] Figure 7 It is a schematic diagram of the upper shear cylinder in Embodiment 2;

[0025] Figure 8 It is Figure 7 The sectional view of the upper shear cylinder in

[0026] In the figure: 1. Pressure chamber; 101. Specimen groove; 102. Water inlet hole; 103. Step joint; 104. Water inlet gap; 2. Lower shear disc; 201. Lower shear column; 202. Permeable disc; 203. Permeable hole; 204. Lower card slot; 205. Fixed column; 206. Guide hole; 3. Upper shear cylinder; 301. Mounting hole; 302. Upper joint; 303. Upper card slot; 304. Limit tooth; 4. Test bench; 401. Water injection hole; 402. Socket; 403. Sealing ring; 5. Bearing base. Detailed implementation mode

[0027] To make the purpose, technical solutions and advantages of the present utility model clearer, the following will further describe the implementation modes of the present utility model with reference to the drawings. The following introduces a relatively optimal one among multiple possible embodiments of the present utility model, aiming to provide a basic understanding of the present utility model, but not aiming to identify the key or decisive elements of the present utility model or limit the scope to be protected.

[0028] In all the examples shown and discussed here, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of the exemplary embodiments may have different values.

[0029] For technologies, methods and equipment known to those of ordinary skill in the relevant field, they may not be discussed in detail, but where appropriate, the said technologies, methods and equipment should be regarded as part of the specification.

[0030] It should be noted that like reference numerals and letters denote like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof in subsequent figures is not necessary. At the same time, it should be understood that, for the sake of convenience of description, the dimensions of the various parts shown in the figures are not drawn in actual proportional relationship.

[0031] In the description of the present utility model, it should be noted that the circuits, electronic components and modules involved in the present utility model are all prior arts, which can be fully implemented by those skilled in the art without further elaboration. The content protected by the present utility model does not involve improvements to the internal structures and methods of circuits and electronic components.

[0032] Furthermore, it should be noted that unless otherwise clearly defined and limited, the terms "installation" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0033] Embodiment 1

[0034] Please refer to Figure 1 and 2 , an in-situ loading micro-ring shear assembly provided by an embodiment of the present utility model is applied to a ring shear apparatus, enabling the ring shear apparatus to be placed inside a CT scanner for X-ray CT scanning. The in-situ loading micro-ring shear assembly mainly includes a pressure chamber 1, a lower shear disc 2, and an upper shear cylinder 3.

[0035] Considering that the in-situ loading micro-ring shear assembly is placed inside a CT scanner for scanning when applied to a ring shear apparatus, in order to improve the imaging accuracy, the in-situ loading micro-ring shear assembly is made of a non-metallic material. For example, in this embodiment, the in-situ loading micro-ring shear assembly is made of PEEK material. Although the in-situ loading micro-ring shear assembly in this embodiment selects PEEK material, in other embodiments, the in-situ loading micro-ring shear assembly can select different non-metallic materials such as acrylic and ceramics.

[0036] Please refer to Figure 4 , 5 and 6, the pressure chamber 1 is provided with a cylindrical specimen groove 101. The pressure chamber 1 is cylindrical, the test groove is coaxially arranged with the pressure chamber 1, and the bottom surface of the specimen groove 101 is provided with a plurality of water inlet holes 102.

[0037] The lower shear disc 2 is arranged in the specimen groove 101. The lower shear disc 2 includes a permeable disc 202 and a lower shear post 201. The permeable disc 202 is installed at the lower end of the lower shear post 201. The lower end of the lower shear post 201 is installed at the bottom of the specimen groove 101. The permeable disc 202 is in contact with the bottom surface of the specimen groove 101. An annular space is formed between the specimen groove 101 and the lower shear post 201.

[0038] Specifically, the permeable disc 202 is arranged around the lower end of the lower shear post 201, and the outer diameter of the permeable disc 202 is approximately the same as the diameter of the specimen groove 101. A fixing post 205 with a reduced diameter is provided below the lower end of the lower shear post 201. A fixing groove is provided in a downward concave shape at the bottom of the specimen groove 101. The fixing post 205 is inserted into the fixing groove and is fixedly connected to the fixing groove by bolts, so that the permeable disc 202 is in contact with the bottom surface of the specimen groove 101.

[0039] Please refer to Figure 3 , the upper end of the upper shear cylinder 3 is closed, and the upper shear cylinder 3 is generally arranged above the pressure chamber 1. When the upper shear cylinder 3 moves downward, it can be inserted into the annular space, so that the outer wall of the upper shear cylinder 3 is in contact with the inner wall of the specimen groove 101, and the inner wall of the upper shear cylinder 3 is in contact with the outer wall of the lower shear post 201. When the lower end of the upper shear cylinder 3 is inserted into the specimen groove 101, the geotechnical specimen in the specimen groove 101 can be axially extruded.

[0040] In some embodiments, in order to ensure the stable vertical downward movement of the upper shear cylinder 3 and accurately insert it into the specimen groove 101, an installation hole 301 is provided at the upper end of the upper shear cylinder 3. A guide post (not shown in the figure) extending vertically downward is installed in the installation hole 301. A vertically arranged guide hole 206 is provided on the lower shear post 201. The guide hole 206 is adapted to the guide post. The lower end of the guide post is inserted into the guide hole 206 and can slide vertically along the guide hole 206. In this way, when the upper shear cylinder 3 moves vertically downward and is inserted into the specimen groove 101, the guide post moves vertically relative to the guide hole 206, preventing the upper shear cylinder 3 from deviating when moving downward.

[0041] In some embodiments, in order to prevent the geotechnical specimen in the specimen groove 101 from sliding, a plurality of downward-extending upper limiting pieces (not shown in the figure) are provided on the bottom surface of the upper shear cylinder 3. The upper limiting pieces are arranged along the diameter direction of the upper shear cylinder 3. The upper limiting pieces can be selected as copper sheets and are embedded in the upper clamping groove 303 on the lower end surface of the upper shear cylinder 3. When the lower end of the upper shear cylinder 3 is inserted into the specimen groove 101, the upper limiting pieces are directly inserted into the geotechnical specimen to limit the sliding of the geotechnical specimen.

[0042] To achieve the installation and fixation of the pressure chamber 1, the in-situ loading micro-ring shear assembly further includes a bearing base 5 and a test bench 4. The test bench 4 is rotatably arranged on the bearing base 5, and the pressure chamber 1 is installed on the test bench 4. Specifically, the lower edge of the pressure chamber 1 is fixedly connected to the test bench 4, and a water inlet gap 104 is formed between the lower end of the pressure chamber 1 and the test bench 4. A plurality of water inlet holes 102 are provided at the bottom of the sample tank 101, and the permeable disk 202 is attached to the bottom surface of the sample tank 101.

[0043] The permeable disk 202 is provided with a plurality of permeable holes 203, and the permeable holes 203 are uniformly distributed on the permeable disk 202. And in order to make the water flow evenly upward into the sample, a plurality of lower limit pieces (not shown in the figure) are provided on the permeable disk 202. Specifically, a plurality of lower clamping grooves 204 are provided on the permeable disk 202, and the lower end of each lower limit piece is clamped into the lower clamping groove 204 for fixation, so that each lower limit piece is arranged along the radial direction of the permeable disk 202, and the permeable disk 202 is evenly divided by the lower limit pieces. The lower limit piece can be clamped into the lower part of the geotechnical sample in the sample tank 101 to prevent the geotechnical sample from sliding.

[0044] In some embodiments, a stepped joint 103 is formed by relative depression on the bottom side of the pressure chamber 1. A receiving slot 402 is provided at the top of the test bench 4. The stepped joint 103 is inserted into the receiving slot 402. A plurality of bolt holes are provided on the side wall of the pressure chamber 1, and bolts are arranged in the bolt holes to be tightly connected to the upper port of the receiving slot 402. The water inlet hole 102 penetrates through the stepped joint 103, and the water inlet gap 104 is formed between the stepped joint 103 and the receiving slot 402. A water injection hole 401 is provided at the bottom of the receiving slot 402. The water injection hole 401 is generally connected to a water source through a rubber tube to inject water into the water injection hole 401. In order to ensure the sealed connection between the outer wall of the stepped joint 103 and the inner wall of the receiving slot 402 and ensure that all the water flow in the water inlet gap 104 flows upward through the water inlet hole 102, a sealing ring 403 is provided between the outer wall of the stepped joint 103 and the inner wall of the receiving slot 402.

[0045] When the in-situ loading micro-ring shear assembly is applied to a ring shear apparatus, it is generally connected to the dynamic loading system of the ring shear apparatus. That is, the upper end of the upper shear cylinder 3 is connected to an axial loading assembly. For example, in this embodiment, the upper end of the upper shear cylinder 3 is provided with an upper joint 302, and is connected to the axial loading assembly through the upper joint 302. The upper shear cylinder 3 can be driven to move up and down through the axial loading assembly. The pressure chamber 1 is connected to a ring shear loading assembly through the lower end of the test bench 4, and the pressure chamber 1 and the lower shear disc 2 are driven to rotate through the ring shear loading assembly. The axial loading assembly and the ring shear loading assembly are generally loading mechanisms driven by motors, which is prior art and will not be elaborated here again.

[0046] Please refer to Figure 1 , the process of applying the in-situ loading micro-ring shear assembly to a ring shear apparatus for a pore water pressure ring shear test is as follows:

[0047] Load a geotechnical sample into the sample slot 101 of the pressure chamber 1, and install the pressure chamber 1 on the test bench 4.

[0048] After installing the in-situ loading micro-ring shear assembly on the ring shear apparatus, place the entire ring shear apparatus on the turntable inside the CT scanner, so that the CT scanner scans the geotechnical sample in the sample slot 101.

[0049] Drive the upper shear cylinder 3 to move downward through the dynamic loading system, so that the lower end of the upper shear cylinder 3 presses the geotechnical sample to reach a predetermined axial pressure.

[0050] Inject water through the water injection hole 401 at the bottom of the pressure chamber 1. The water flows into the water inlet gap 104, then passes through the water inlet hole 102 and the lower limit piece on the permeable disc 202, and enters the geotechnical sample to provide pore water pressure for the geotechnical sample.

[0051] Drive the pressure chamber 1 and the lower shear disc 2 to rotate through the dynamic loading system to simulate a pore water pressure ring shear test.

[0052] The CT scanner scans and images the geotechnical sample to obtain the microscopic change process of the geotechnical sample under circumferential shear.

[0053] Embodiment 2

[0054] As Figure 7 and 8As shown, in Embodiment 2 of the present application, in order to better prevent the geotechnical sample in the sample tank 101 from sliding during the test, the bottom surface of the upper shear cylinder 3 is provided with limiting teeth 304, and the limiting teeth 304 are arranged in a circle along the bottom surface of the upper shear cylinder 3. When the upper shear cylinder 3 is inserted into the sample tank 101 filled with the geotechnical sample, the limiting teeth 304 are inserted into the upper part of the geotechnical sample. In this way, the sliding of the geotechnical sample is effectively restricted by the limiting teeth 304, so that the pressure chamber 1 and the lower shear disc 2 can rotate to stably perform circular shear on the geotechnical sample, ensuring the smooth progress of the pore water pressure circular shear test.

[0055] In this article, the front, back, upper, lower and other orientation words are defined based on the positions of the components in the drawings and the positions of the components relative to each other, only for the sake of clarity and convenience in expressing the technical solution. It should be understood that they are relative concepts and can change accordingly according to different usage and placement methods. The use of the orientation words should not limit the scope of protection claimed in the present application.

[0056] Without conflict, the above-mentioned embodiments and the features in the embodiments in this article can be combined with each other. The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An in-situ loading micro-ring shear assembly, characterized in that, Comprising: A pressure chamber provided with a cylindrical specimen groove, and a plurality of water inlet holes are provided on the bottom surface of the specimen groove; A lower shear disc, which includes a permeable disc and a lower shear column. The permeable disc is installed at the lower end of the lower shear column, the lower end of the lower shear column is installed at the bottom of the specimen groove, and the permeable disc is attached to the bottom surface of the specimen groove, so that an annular space is formed between the specimen groove and the lower shear column; An upper shear cylinder, the upper end of which is closed. The upper shear cylinder can be inserted into the annular space, so that the outer wall of the upper shear cylinder is attached to the inner wall of the specimen groove, and the inner wall of the upper shear cylinder is attached to the outer wall of the lower shear column.

2. The in-situ loading micro-ring shear assembly according to claim 1, wherein: It further includes a bearing base and a test bench. The test bench is rotatably arranged on the bearing base. The lower end edge of the pressure chamber is fixedly connected to the test bench, and a water inlet gap is formed between the lower end of the pressure chamber and the test bench. The test bench is provided with a water injection hole, and the upper end of the water injection hole is communicated with the water inlet gap.

3. The in-situ loading micro-ring shear assembly according to claim 2, characterized in that: The permeable disc is arranged around the lower end of the lower shear column. The lower end of the lower shear column is provided with a fixed column with a reduced diameter below the permeable disc. The bottom of the specimen groove is provided with a downwardly concave fixed groove. The fixed column is inserted into the fixed groove and tightly connected with the fixed groove, so that the permeable disc is attached to the bottom surface of the specimen groove.

4. The in-situ loading micro-ring shear assembly according to claim 2 or 3, characterized in that: The bottom side of the pressure chamber is relatively recessed to form a stepped joint. The top of the test bench is provided with a receiving slot. The stepped joint is inserted into the receiving slot. The bottom of the side wall of the pressure chamber is tightly connected to the upper port of the receiving slot. The water inlet hole penetrates through the stepped joint. The water inlet gap is formed between the stepped joint and the receiving slot. The water injection hole is arranged at the bottom of the receiving slot.

5. The in-situ loading micro-ring shear assembly according to claim 4, characterized in that: A sealing ring is arranged between the outer wall of the stepped joint and the inner wall of the receiving slot.

6. The in-situ loading micro-ring shear assembly according to claim 1, wherein: The top of the upper shear cylinder is provided with a guide post extending vertically downward. The lower shear column is provided with a vertically arranged guide hole. The lower end of the guide post is inserted into the guide hole.

7. The in-situ loading micro-ring shear assembly according to claim 1, wherein: The permeable disc is provided with a plurality of permeable holes, and the permeable disc is further provided with a plurality of lower limit pieces. The lower limit pieces are arranged along the radial direction of the permeable disc, and each lower limit piece evenly divides the permeable disc.

8. The in-situ loading micro-ring shear assembly according to claim 1, wherein: The upper end of the upper shear cylinder is provided with an upper joint.

9. The in-situ loading micro-ring shear assembly according to claim 1, characterized in that: The bottom surface of the upper shear cylinder is provided with a plurality of upper limit pieces extending downward.

10. The in-situ loading micro-ring shear assembly according to claim 1, wherein: The bottom surface of the upper shear cylinder is provided with limit teeth.

Images