Combined rock sample shearing-seepage test device and working method

Abstract

This invention discloses a combined rock sample shear-permeability test apparatus and its working method, relating to the field of rock shear-permeability testing technology. It includes a first support body, a second support body, a third support body, and a fourth support body, which are combined to form a cubic shear box. The lower grooves of the first and second support bodies, together with the upper grooves of the third and fourth support bodies, form a closed cavity capable of accommodating the rock sample. The inner walls of both the upper and lower grooves are coated with a thin-walled rubber layer, and an annular sealing ring is provided on the outer edge of each groove. Two sets of permeability holes are respectively provided on the inner walls of the lower and upper grooves. Two water pipe joints on the front side of each support body are connected to the two sets of permeability holes on that support body via water channels. This invention meets the requirements for axial and radial shear testing of rock samples, providing theoretical support for studying the coupling effect when the shear direction and permeability direction of rock samples are inconsistent.

Description

Technical Field

[0001] This invention relates to the field of rock shear permeability testing technology, specifically to a combined rock sample shear-permeability testing device and its working method. Background Technology

[0002] Rock mechanical properties and permeability failure testing can provide a scientific basis for the design, construction, and safety assessment of rock engineering. Through indoor uniaxial / triaxial compression tests, Brazilian splitting tests, and shear tests, key indicators such as deformation, strength, failure, and permeability of rocks under different stress states can be obtained. Rock shear failure is one of the common failure modes in deep coal mines and dam / tunnel engineering. To study the shear failure mechanism, it is usually necessary to process cylindrical, cubic, or prismatic rock specimens of specified dimensions and conduct direct shear or permeable shear tests on the rock specimens using RMT301, RockTop multi-field multiphase coupling testing equipment, rock stress-seepage coupled true triaxial testing systems, or other improved equipment.

[0003] However, existing testing equipment is typically only suitable for rock samples of fixed dimensions, making it difficult to conduct shear tests on rock samples of different shapes. The mold shear and seepage modes are limited and cannot meet the testing requirements for different shear directions of rock samples with layered structures (such as shale and slate). Furthermore, in practical engineering projects such as coal mines, tunnels, and underground chambers (e.g., isolating coal-rock pillars in water-filled inclined roadways), the stress direction of the rock mass and the seepage direction of water often do not align. Therefore, existing testing equipment cannot meet practical needs. Based on this, it is necessary to design a rock sample shear-seepage coupling device and propose a corresponding testing method. Summary of the Invention

[0004] To address the shortcomings of the existing technologies, one objective of this invention is to propose a combined rock sample shear-seepage test device. This device solves the problems of existing shear-seepage test equipment having a single mode, being unable to meet the requirements of radial and axial shear on the same device, having poor versatility, and being unable to simulate the coupling effect when the shear direction and seepage direction are relatively inclined.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0006] A combined rock sample shear-seepage test device includes a first support body, a second support body, a third support body, and a fourth support body. All four support bodies are rectangular structures of the same specifications and can be combined to form a cubic shear box.

[0007] The first and second load cells are arranged adjacent to each other on the left and right. The third and fourth load cells are respectively located directly above the first and second load cells. The third and fourth load cells are arranged adjacent to each other. The front and rear sides of each load cell can be bolted to the corresponding sides of the adjacent load cells.

[0008] The third carrier is laterally slidably engaged with the first carrier through a linear guide component one; the fourth carrier is laterally slidably engaged with the second carrier through the same linear guide component one; the fourth carrier is vertically slidably engaged with the third carrier through a linear guide component two; and the second carrier is vertically slidably engaged with the first carrier through the same linear guide component two.

[0009] The right side walls of the first and third bearings and the left side walls of the second and fourth bearings adhere to each other to form an axial shear surface for the rock sample. In addition, the upper surfaces of the first and second bearings and the lower surfaces of the third and fourth bearings adhere to each other to form a radial shear surface for the rock sample.

[0010] The first and second carriers each have a lower groove on one adjacent side, and the third and fourth carriers each have an upper groove on one adjacent side. The two upper grooves and the two lower grooves form a closed cavity that can accommodate the rock sample. The inner walls of the upper and lower grooves are coated with a thin rubber coating.

[0011] An annular sealing ring is provided on the outer edge of both the upper and lower grooves. Each annular sealing ring is fixed in an embedded manner to the two adjacent side walls of the carrier in which the inner groove is located. The corresponding parts of the annular sealing rings on the adjacent side walls of any two adjacent carriers are staggered.

[0012] The lower groove has a set of seepage holes on its side wall and bottom wall, and the upper groove has a set of seepage holes on its side wall and top wall. Each set of seepage holes includes multiple seepage holes, and each seepage hole is equipped with a sealing plug.

[0013] Each carrier is equipped with a water pipe joint 1 and a water pipe joint 2 on its front side wall. The two water pipe joints on the same carrier are connected to two sets of seepage holes on the carrier through independent water channels.

[0014] Furthermore, all four carriers are arranged horizontally along their length, and the front and rear sidewalls of the shear box each have four sets of square grooves, each set of square grooves including two square grooves arranged at intervals.

[0015] Two of the four sets of square grooves located on the same sidewall are arranged at intervals along the extension direction of the radial shear plane and are located on both sides of the axial shear plane, respectively. The other two sets of square grooves are arranged at intervals along the extension direction of the axial shear plane and are located on both sides of the radial shear plane, respectively.

[0016] The two square grooves in the same group are located on two adjacent bearings, and each adjacent side is close to the radial shear surface or the axial shear surface.

[0017] Furthermore, bolt holes are provided on the adjacent sides of the two square grooves in the same group, and the two bolt holes are coaxial and face each other.

[0018] Each set of square grooves is equipped with a bolt assembly, which includes a hexagonal bolt and a nut. The hexagonal bolt is inserted into the corresponding bolt hole through one of the square grooves in the same set, and the nut is tightened at the end of the hexagonal bolt through another square groove, so that the two adjacent load-bearing bodies are connected into one.

[0019] When the rock sample is subjected to axial shearing, the first and third bearing bodies are fixedly connected to form the left box, and the second and fourth bearing bodies are fixedly connected to form the right box.

[0020] When the rock sample is subjected to radial shearing, the first and second support bodies are fixedly connected to form the lower box, and the third and fourth support bodies are fixedly connected to form the upper box.

[0021] Furthermore, both the upper and lower grooves are semi-cylindrical structures, with the upper end of the lower groove extending to the upper surface of the first or second support body, and the lower end of the upper groove extending to the bottom surface of the third or fourth support body.

[0022] The two upper grooves combine to form a cylindrical cavity with its opening facing downwards, and the two lower grooves combine to form a cylindrical cavity with its opening facing upwards. The two cylindrical cavities combine to form the closed cavity.

[0023] The annular sealing ring includes a semi-circular arc section and a U-shaped section. The semi-circular arc section and the U-shaped section are located on two mutually perpendicular planes. The two ends of the U-shaped section are fixedly connected to the two ends of the semi-circular arc section to form a whole.

[0024] Furthermore, both the upper and lower grooves are square structures, with the lower end of the upper groove extending to the bottom surface of the third or fourth support body, and the upper end of the lower groove extending to the upper surface of the first or second support body.

[0025] The two upper grooves combine to form a square cavity with its opening facing downwards, the two lower grooves combine to form a square cavity with its opening facing upwards, and the two square cavities combine to form the closed cavity.

[0026] The annular sealing ring includes two U-shaped sections of the same size, which are located on two mutually perpendicular planes. The two ends of one U-shaped section are fixedly connected to the two ends of the other U-shaped section to form a whole.

[0027] Furthermore, a set of limiting grooves is provided on the side of the upper surface of the first and second carriers that are far apart from each other, and each set of limiting grooves includes two limiting grooves distributed at intervals.

[0028] The first and second carriers each have a tunnel cavity I with the same number and position as the limiting groove I. Each tunnel cavity I extends laterally and is located on the side of its corresponding limiting groove I near the axial shear surface. The tunnel cavity I communicates with the corresponding limiting groove I.

[0029] Furthermore, the bottom of the third and fourth carriers are each provided with two linear guide components. The linear guide component includes a positioning slide and a dovetail guide rail. The positioning slide is fixed to the bottom surface of the third or fourth carrier, and the dovetail guide rail is located inside the positioning slide and slides laterally with it.

[0030] The two positioning slides at the bottom of the third carrier are respectively embedded in the two limiting grooves of the first carrier, and the two positioning slides at the bottom of the fourth carrier are respectively embedded in the two limiting grooves of the second carrier.

[0031] When the positioning slide is embedded in the inner side of the corresponding limiting groove, one end of the dovetail guide rail on its inner side passes into the tunnel cavity communicating with the limiting groove, and the other end of the dovetail guide rail is detachably and fixedly connected to the positioning slide by a locking screw.

[0032] Furthermore, a set of limiting grooves II is provided on the side of the right side wall of the first and third bearings that are far apart from each other, and each set of limiting grooves II includes two limiting grooves II arranged one in front of the other.

[0033] The first and third carriers each have a tunnel cavity two that is equal in number and corresponding in position to the limiting groove two. Each tunnel cavity two extends vertically and is located on the side of its corresponding limiting groove two near the radial shear surface. The tunnel cavity two communicates with the corresponding limiting groove two.

[0034] Furthermore, two linear guide components are provided on the left side of both the second and fourth carriers. The linear guide components include a positioning slide and a dovetail guide. The positioning slide is fixed to the left side wall of the second or fourth carrier, and the dovetail guide is located inside the positioning slide and slides vertically with it.

[0035] The two positioning slides on the left side of the second carrier are respectively embedded in the two limiting grooves of the first carrier, and the two positioning slides on the left side of the fourth carrier are respectively embedded in the two limiting grooves of the third carrier.

[0036] When the positioning slide 2 is embedded inside the corresponding limiting groove 2, one end of the dovetail guide rail 2 inside it passes into the tunnel cavity 2 that communicates with the limiting groove 2, and the other end of the dovetail guide rail 2 is detachably and fixedly connected to the positioning slide 2 by the same locking screw.

[0037] Another objective of this invention is to provide a method for operating a combined rock sample shear-seepage test apparatus.

[0038] A method for operating a combined rock specimen shear-seepage testing device, based on the aforementioned combined rock specimen shear-seepage testing device, includes the following steps:

[0039] S1. According to the requirements of the experimental design, determine the shear mode and seepage mode for the rock sample. There are two shear modes: radial shear mode and axial shear mode.

[0040] There are three types of seepage: the seepage direction is parallel to the shear direction, the seepage direction is perpendicular to the shear direction, and the seepage direction is relatively inclined to the shear direction.

[0041] According to the requirements of the experimental design, the corresponding rock samples were processed and prepared.

[0042] S2. Based on the seepage method determined in S1, select the seepage holes as inlet and outlet, and seal all the remaining seepage holes with sealing plugs.

[0043] If the radial shear mode is adopted, the first and second carriers are placed side by side, the rock sample is placed in the lower groove of the first and second carriers, and the first and second carriers are fixedly connected to form the lower box.

[0044] Next, the third and fourth carriers are placed on the left and right sides of the top of the lower box, respectively, and the third and fourth carriers are pushed to move horizontally relative to each other to achieve closure. Then, the front and rear ends of the third and fourth carriers are fixedly connected to form the upper box.

[0045] At this point, the rock sample is encapsulated in the closed cavity of the shear box, and the upper box can slide and seal with the lower box laterally.

[0046] If the axial shear mode is adopted, the third support body and the first support body are placed adjacent to each other, the rock sample is placed in the lower groove of the first support body and the upper groove of the third support body, and the first and third support bodies are fixedly connected to form the left box body.

[0047] Then, the second and fourth carriers are placed to the right of the first and third carriers respectively, and the second and fourth carriers are pushed to move vertically relative to each other to achieve closure. After that, the second and fourth carriers are fixedly connected to form the right side box.

[0048] At this point, the rock sample is encapsulated in the closed cavity of the shear box, and the right side of the box can slide and seal vertically with the left side of the box.

[0049] S3. Initialize and adjust the shear loading device. The horizontal loading cylinder of the shear loading device is in the retracted state.

[0050] The shear box assembled in radial shear mode is moved to the worktable of the shear loading device, or the shear box assembled in axial shear mode is rotated 90° around the intersection line of the axial shear plane and the radial shear plane and then moved to the worktable of the shear loading device, so that the carrier where the water inlet seepage hole is located is below the carrier where the drainage seepage hole is located.

[0051] S4. Connect the inlet pipe of the water supply device used for the rock seepage experiment to the water pipe joint corresponding to the seepage hole of the inlet water, and connect the return pipe of the water supply device to the water pipe joint corresponding to the seepage hole of the outlet water.

[0052] According to the experimental design requirements, firstly, the vertical loading cylinder is activated, and the telescopic end of the vertical loading cylinder applies a vertical force to the top of the shear box through the ball bearing plate.

[0053] Then, the horizontal loading cylinder is activated, and the telescopic end of the horizontal loading cylinder applies a horizontal force to the outer wall of the shear box through the loading plate. At the same time, the water supply device starts working, supplying water to the closed cavity of the shear box to obtain relevant experimental data.

[0054] After the test, the horizontal loading cylinder was returned to its initial state, and the connection between the shear box and the water supply device was disconnected.

[0055] After the rock sample is removed, each support structure is disassembled, and the support structures and the worktable of the shear loading equipment are cleaned.

[0056] By adopting the above technical solution, the beneficial technical effects of the present invention are as follows:

[0057] 1. The present invention offers diverse shear directions. It is applicable to shear tests on various types of rock samples, especially for layered rock samples, allowing for axial or radial shearing, and is used to simulate rock samples under the coupled effects of shear and seepage.

[0058] 2. The present invention adopts a modular splicing structure, which can meet the requirements of radial shearing mode or axial shearing mode on a single device, and realize the application of shearing force to cylindrical (or cuboid) rock samples along the axial or radial section. The structure is flexible to assemble and easy to operate. The present invention has good sealing performance and reliability by adopting a double-layer sealing structure at the interface.

[0059] 3. The diversity of shear mode and seepage method coupling in this invention. This invention combines both pure shear and shear-seepage measurement modes, meeting the testing requirements for rock sample shearing processes where the seepage direction is parallel to the shear direction, perpendicular to the shear direction, and at an inclined angle to the shear direction. Attached Figure Description

[0060] Figure 1 This is a schematic diagram of the structure of a combined rock sample shear-seepage test device according to the present invention.

[0061] Figure 2 This is a schematic diagram of the first embodiment of a combined rock sample shear-seepage test device of the present invention.

[0062] Figure 3 This is an exploded view of the first embodiment of a combined rock sample shear-seepage test device of the present invention.

[0063] Figure 4 This is a schematic diagram of the structure of the annular sealing ring according to the first embodiment of the present invention.

[0064] Figure 5 This is an exploded structural diagram of the linear guide component of the present invention.

[0065] Figure 6 This is an exploded structural diagram of the linear guide component II of the present invention.

[0066] Figure 7 This is a schematic diagram of a second embodiment of a combined rock sample shear-seepage test device of the present invention.

[0067] Figure 8 This is an exploded view of a second embodiment of a combined rock sample shear-seepage test device of the present invention.

[0068] Figure 9 This is a schematic diagram of the structure of the annular sealing ring according to the second embodiment of the present invention.

[0069] Figure 10 This is a diagram showing the usage of the present invention in radial shear mode.

[0070] Figure 11 This is a diagram showing the usage of the present invention in axial shear mode.

[0071] The figure shows: 1. First bearing body; 101. Axial shear surface; 102. Radial shear surface; 11. Square groove; 12. Bolt hole; 13. Bolt assembly; 14. Closed cavity; 2. Second bearing body; 3. Third bearing body; 4. Fourth bearing body; 51. Upper groove; 52. Lower groove; 53. Annular sealing ring; 531. Semi-circular arc section; 532. U-shaped section; 54. Seepage hole; 55. Water pipe joint one; 56. Water pipe joint two; 61. Limiting groove one; 6 2. Tunnel Cavity 1; 63. Positioning Slide 1; 64. Dovetail Guide Rail 1; 65. Square Connecting Block 1; 66. Settling Tank 1; 71. Limiting Slot 2; 72. Tunnel Cavity 2; 73. Positioning Slide 2; 74. Dovetail Guide Rail 2; 75. Square Connecting Block 2; 76. Settling Tank 2; 81. Workbench; 82. Limiting Seat; 83. Hydraulic Cylinder Support; 84. Horizontal Loading Hydraulic Cylinder; 85. Loading Plate; 86. Force Sensor; 87. Vertical Loading Hydraulic Cylinder; 88. Reaction Frame; 89. Ball Plate. Detailed Implementation

[0072] To make the advantages and technical solutions of the present invention clearer and more explicit, the present invention will be described in detail below with reference to specific embodiments.

[0073] Example 1, combined with Figures 1 to 6 A combined rock sample shear-seepage test device includes four carriers, namely a first carrier 1, a second carrier 2, a third carrier 3 and a fourth carrier 4. All four carriers are rectangular structures of the same specifications and are arranged horizontally along their length direction, which can be combined to form a cubic shear box.

[0074] The first support body 1 and the second support body 2 are arranged adjacent to each other on the left and right. The third support body 3 and the fourth support body 4 are respectively located directly above the first support body 1 and the second support body 2. The third support body 3 and the fourth support body 4 are arranged adjacent to each other. The front and rear sides of each support body can be bolted to the corresponding side of the adjacent support body. The adjacent side walls of the two support bodies that are bolted together are tightly fitted together.

[0075] Specifically, the front and rear sidewalls of the shear box each have four sets of square grooves 11, each set including two square grooves 11 arranged at intervals. Each set of square grooves 11 is equipped with a bolt assembly 13, which includes a hexagonal bolt and a nut. The hexagonal bolt passes through one of the square grooves 11 in the same set into its corresponding bolt hole 12, and the nut is tightened onto the end of the hexagonal bolt through the other square groove 11, thus connecting two adjacent load-bearing bodies into one unit. All bolt assemblies 13 of this invention are embedded in the sidewalls of the shear box, minimizing the requirements on the shearing loading equipment during use and improving versatility.

[0076] Two of the four sets of square grooves 11 located on the same sidewall are arranged at intervals along the extension direction of the radial shear surface 102 and are located on both sides of the axial shear surface 101, respectively. The other two sets of square grooves 11 are arranged at intervals along the extension direction of the axial shear surface 101 and are located on both sides of the radial shear surface 102, respectively.

[0077] The two square grooves 11 in the same group are located on two adjacent bearings, and each adjacent side is close to the radial shear surface 102 or the axial shear surface 101. Bolt holes 12 are respectively opened on the adjacent side of the two square grooves 11 in the same group, and the two bolt holes 12 are coaxial and positively aligned.

[0078] The right side walls of the first support body 1 and the third support body 3 are bonded to the left side walls of the second support body 2 and the fourth support body 4 to form an axial shear surface 101 for the rock sample. In addition, the upper surfaces of the first support body 1 and the second support body 2 are bonded to the lower surfaces of the third support body 3 and the fourth support body 4 to form a radial shear surface 102 for the rock sample.

[0079] When the rock sample is subjected to axial shearing, the front and rear ends of the first support body 1 and the third support body 3 are fixedly connected by bolt assemblies 13 to form the left box body. The right side wall of the first support body 1 is flush with the right side wall of the third support body 3. The front and rear ends of the second support body 2 and the fourth support body 4 are also fixedly connected by bolt assemblies 13 to form the right box body. The left side wall of the second support body 2 is flush with the left side wall of the fourth support body 4. In use, the right side wall of the left box body and the left side wall of the right box body are kept in close contact and can slide relative to each other.

[0080] When the rock sample is radially sheared, the front and rear ends of the first support body 1 and the second support body 2 are fixedly connected by bolt assemblies 13 to form a lower box body. The upper surface of the first support body 1 is flush with the upper surface of the second support body 2. The front and rear ends of the third support body 3 and the fourth support body 4 are also fixedly connected by bolt assemblies 13 to form an upper box body. The bottom surface of the third support body 3 is flush with the bottom surface of the fourth support body 4. In use, the bottom surface of the upper box body and the upper surface of the lower box body are in close contact and can slide relative to each other.

[0081] The first support body 1 and the second support body 2 each have a lower groove 52 with the same structure on their adjacent sides, and the third support body 3 and the fourth support body 4 each have an upper groove 51 with the same structure on their adjacent sides. The two upper grooves 51 and the two lower grooves 52 form a closed cavity 14 that can accommodate the rock sample.

[0082] Specifically, both the upper groove 51 and the lower groove 52 are semi-cylindrical cavities. The upper end of the lower groove 52 extends to the upper surface of the first support 1 or the second support 2, and the lower end of the upper groove 51 extends to the bottom surface of the third support 3 or the fourth support 4. The two upper grooves 51 combine to form a downward-opening cylindrical cavity, and the two lower grooves 52 combine to form an upward-opening cylindrical cavity. The two cylindrical cavities combine to form the closed cavity 14.

[0083] It is particularly important to note that the inner walls of each of the upper grooves 51 and the lower grooves 52 are coated with a thin-walled rubber coating. The thin-walled rubber coating preferably uses silicone rubber with excellent elasticity. After the four carriers are assembled, the thin-walled rubber coatings located inside the carriers form an encapsulation structure that wraps around the outside of the rock sample. The size of the rock sample is slightly larger than the cavity size of the encapsulation structure. By utilizing the elastic micro-deformation of the thin-walled rubber coating, its surface is tightly attached to the outer surface of the rock sample. Water will only seep through the interior of the rock sample and will not seep along its surface, thus ensuring the accuracy and reliability of the test.

[0084] Furthermore, an annular sealing ring 53 is provided on the outer edge of both the upper groove 51 and the lower groove 52. The annular sealing ring 53 includes a semi-circular arc section 531 and a U-shaped section 532. The semi-circular arc section 531 and the U-shaped section 532 are located on two mutually perpendicular planes. The two ends of the U-shaped section 532 are fixedly connected to the two ends of the semi-circular arc section 531 to form a single unit. Each annular sealing ring 53 is fixedly embedded in the two adjacent side walls of the carrier body where its inner groove is located. The corresponding portions of the annular sealing rings 53 located on the adjacent side walls of any two adjacent carrier bodies are staggered.

[0085] For the annular sealing ring 53 on the first carrier 1, the semi-circular arc section 531 of the annular sealing ring 53 is located on the upper surface of the first carrier 1, and its U-shaped section 532 is located on the right side wall of the first carrier 1. The annular sealing rings 53 on the other carriers are arranged in the same manner. The outer surface of the annular sealing ring 53 is an arc-shaped curved surface, with both sides along its length flush with the outer wall of the carrier on which it is located, and the middle part slightly higher than the outer wall of the carrier. In addition, the annular sealing ring 53 on the first carrier 1 is the same size as the annular sealing ring 53 on the fourth carrier 4, and the annular sealing ring 53 on the second carrier 1 is the same size as the annular sealing ring 53 on the third carrier 2. The size of the annular sealing ring 53 on the first carrier 1 is larger than the size of the annular sealing ring 53 on the fourth carrier 4. After the four carriers are assembled, the annular sealing rings 53 on any two adjacent carriers are pressed together to form a double-layer sealing structure at the interface, which can effectively prevent leakage.

[0086] The lower groove 52 has a set of seepage holes 54 on its sidewall and bottom wall, and the upper groove 51 has a set of seepage holes 54 on its sidewall and top wall. Each set of seepage holes 54 includes three seepage holes 54 arranged linearly and at equal intervals. The three seepage holes 54 on the sidewall of the upper groove 51 or the sidewall of the lower groove 52 are distributed along the centerline of the semi-circular arc surface. That is, the three seepage holes 54 on the sidewall of the first support body 1 are arranged opposite to the three seepage holes 54 on the sidewall of the second support body 1, and the three seepage holes 54 on the sidewall of the third support body 1 are also arranged opposite to the three seepage holes 54 on the sidewall of the fourth support body 1. In addition, the three seepage holes 54 on the top wall of the upper groove 51 and the three seepage holes 54 on the bottom wall of the lower groove 52 are arranged longitudinally and opposite to each other vertically. As a preferred embodiment, the end of the seepage hole 54 adopts a conical structure, and each seepage hole 54 is equipped with a sealing plug. The sealing plug is a rubber plug with an internal rigid skeleton, and the shape of its outer wall is consistent with the shape of the inner wall of the corresponding groove, so as to ensure that the sealing plug will not leak water after sealing the corresponding seepage hole 54.

[0087] Each carrier has two water pipe joints on its front side wall. The two water pipe joints are water pipe joint 1 55 and water pipe joint 2 56. The two water pipe joints on the same carrier are connected to two sets of seepage holes 54 on the carrier through independent water channels 57. The three seepage holes 54 in the same set can be used as both water inlets and water outlets. The connection method between the two water pipe joints and the water supply device can be determined according to the actual use. The water supply device adopts existing technology.

[0088] The third carrier 3 is laterally slidably engaged with the first carrier 1 through a linear guide component 1, and the fourth carrier 4 is laterally slidably engaged with the second carrier 2 through the same linear guide component 1.

[0089] Specifically, a set of limiting grooves 61 is provided on the upper surfaces of the first support body 1 and the second support body 2 on opposite sides. Each set of limiting grooves 61 includes two limiting grooves 61 spaced apart. The limiting grooves 61 have a square cross-section and extend laterally. The first support body 1 and the second support body 2 each have a tunnel cavity 62 with the same number and position as the limiting grooves 61. The tunnel cavity 62 has a dovetail cross-section, extends laterally, and is located on the side of its corresponding limiting groove 61 near the axial shear surface 101. One end of the tunnel cavity 62 communicates with the corresponding limiting groove 61, and the other end extends to the side wall of the support body.

[0090] Both the third support body 3 and the fourth support body 4 are equipped with two linear guide components at their bottoms. Each linear guide component includes a positioning slide 63 and a dovetail guide rail 64. The positioning slide 63 is fixed to the bottom surface of the third support body 3 or the fourth support body 4, and the dovetail guide rail 64 is located inside the positioning slide 63 and slides laterally with it. The cross-section of the positioning slide 63 matches the cross-section of the limiting groove 61, and the cross-section of the dovetail guide rail 64 matches the cross-section of the tunnel cavity 62.

[0091] A square connecting block 65 is fixed to one side of the end of the dovetail guide rail 64. The end face of the positioning slide 63 has a groove 66 that matches the square connecting block 65. The through hole of the square connecting block 65 is equipped with a locking screw. The dovetail guide rail 64 slides relative to the positioning slide 63 until the square connecting block 65 enters the groove 66. The dovetail guide rail 64 and the positioning slide 63 are fixedly connected together by the locking screw.

[0092] During assembly, the fixed connection between the dovetail guide rail 64 and the positioning slide 63 can be released as needed, and the dovetail guide rail 64 can be pulled outward to ensure that the two positioning slides 63 at the bottom of the third carrier 3 are respectively embedded inside the two limiting grooves 61 of the first carrier 1, and the two positioning slides 63 at the bottom of the fourth carrier 4 are respectively embedded inside the two limiting grooves 61 of the second carrier 2. Then, the dovetail guide rail 64 is pushed inward, and one end of the dovetail guide rail 64 enters the corresponding tunnel cavity 62. After it is in place, the other end of the dovetail guide rail 64 is fixedly connected to the positioning slide 63 by locking screws, so that the bottom surfaces of the third carrier 3 and the fourth carrier 4 are respectively in close contact with the upper surfaces of the first carrier 1 and the second carrier 2, ensuring a sealed fit at the shearing surface during radial shearing.

[0093] The fourth carrier 4 is vertically slidably engaged with the third carrier 3 through the second linear guide component, and the second carrier 2 is vertically slidably engaged with the first carrier 1 through the same second linear guide component.

[0094] Specifically, a set of limiting grooves 71 is provided on the side of the right side wall of the first support body 1 and the third support body 3 that are far apart from each other. Each set of limiting grooves 71 includes two limiting grooves 71 arranged one in front of the other. The limiting grooves 71 have a square cross-section and extend vertically. The first support body 1 and the third support body 3 each have a tunnel cavity 72 that is equal in number and corresponds one-to-one with the limiting grooves 71. Each tunnel cavity 72 has a dovetail-shaped cross-section, extends vertically, and is located on the side of its corresponding limiting groove 71 near the radial shear surface 102. The tunnel cavity 72 communicates with the corresponding limiting groove 71.

[0095] Both the second support body 2 and the fourth support body 4 have two linear guide components on their left sides. Each linear guide component includes a positioning slide 73 and a dovetail guide rail 74. The positioning slide 73 is fixed to the left side wall of the second or fourth support body 4, and the dovetail guide rail 74 is located inside the positioning slide 73 and slides vertically with it. The cross-section of the positioning slide 73 matches the cross-section of the limiting groove 71, and the cross-section of the dovetail guide rail 74 matches the cross-section of the tunnel cavity 72.

[0096] A square connecting block 75 is fixed to one side of the end of the dovetail guide rail 2 74. The end face of the positioning slide 2 73 has a countersunk groove 2 76 that matches the square connecting block 2 75. The square connecting block 2 75 has a through hole with the same locking screw. The dovetail guide rail 2 74 can slide relative to the positioning slide 2 73 until the square connecting block 2 75 enters the inside of the countersunk groove 2 76. The dovetail guide rail 2 74 and the positioning slide 2 73 are fixedly connected together by the locking screw.

[0097] During assembly, the fixed connection between the dovetail guide rail 2 74 and the positioning slide 2 73 can be released as needed, and the relative positions of the dovetail guide rail 2 74 and the positioning slide 2 73 can be adjusted to ensure that the two positioning slides 2 73 on the left side of the second carrier 2 are respectively embedded in the two limiting grooves 2 71 of the first carrier 1, and the two positioning slides 2 73 on the left side of the fourth carrier 4 are respectively embedded in the two limiting grooves 2 71 of the third carrier 3. When the positioning slide 2 73 is embedded in the inner side of the corresponding limiting groove 2 71, the dovetail guide rail 2 74 is pushed inward so that one end of the dovetail guide rail 2 74 enters the tunnel cavity 2 72 that communicates with the limiting groove 2 71. Then, the other end of the dovetail guide rail 2 74 is fixedly connected to the positioning slide 2 73, so that the right side walls of the first carrier 1 and the third carrier 3 are respectively close to the right side walls of the second carrier 2 and the fourth carrier 4, ensuring a sealed fit at the shearing surface during axial shearing.

[0098] Example 2, combined with Figure 1 and Figures 5 to 9A combined rock sample shear-seepage test device includes four carriers, namely a first carrier 1, a second carrier 2, a third carrier 3 and a fourth carrier 4. All four carriers are rectangular structures of the same specifications and are arranged horizontally along their length direction, which can be combined to form a cubic shear box.

[0099] The first support body 1 and the second support body 2 are arranged adjacent to each other on the left and right. The third support body 3 and the fourth support body 4 are respectively located directly above the first support body 1 and the second support body 2. The third support body 3 and the fourth support body 4 are arranged adjacent to each other. The front and rear sides of each support body can be bolted to the corresponding side of the adjacent support body. The adjacent side walls of the two support bodies that are bolted together are tightly fitted together.

[0100] Specifically, the front and rear sidewalls of the shear box each have four sets of square grooves 11, each set including two square grooves 11 arranged at intervals. Each set of square grooves 11 is equipped with a bolt assembly 13, which includes a hexagonal bolt and a nut. The hexagonal bolt passes through one of the square grooves 11 in the same set into its corresponding bolt hole 12, and the nut is tightened onto the end of the hexagonal bolt through the other square groove 11, thus connecting two adjacent load-bearing bodies into one unit. All bolt assemblies 13 of this invention are embedded in the sidewalls of the shear box, minimizing the requirements on the shearing loading equipment during use and improving versatility.

[0101] Two of the four sets of square grooves 11 located on the same sidewall are arranged at intervals along the extension direction of the radial shear surface 102 and are located on both sides of the axial shear surface 101, respectively. The other two sets of square grooves 11 are arranged at intervals along the extension direction of the axial shear surface 101 and are located on both sides of the radial shear surface 102, respectively.

[0102] The two square grooves 11 in the same group are located on two adjacent bearings, and each adjacent side is close to the radial shear surface 102 or the axial shear surface 101. Bolt holes 12 are respectively opened on the adjacent side of the two square grooves 11 in the same group, and the two bolt holes 12 are coaxial and positively aligned.

[0103] The right side walls of the first support body 1 and the third support body 3 are bonded to the left side walls of the second support body 2 and the fourth support body 4 to form an axial shear surface 101 for the rock sample. In addition, the upper surfaces of the first support body 1 and the second support body 2 are bonded to the lower surfaces of the third support body 3 and the fourth support body 4 to form a radial shear surface 102 for the rock sample.

[0104] When the rock sample is subjected to axial shearing, the front and rear ends of the first support body 1 and the third support body 3 are fixedly connected by bolt assemblies 13 to form the left box body. The right side wall of the first support body 1 is flush with the right side wall of the third support body 3. The front and rear ends of the second support body 2 and the fourth support body 4 are also fixedly connected by bolt assemblies 13 to form the right box body. The left side wall of the second support body 2 is flush with the left side wall of the fourth support body 4. In use, the right side wall of the left box body and the left side wall of the right box body are kept in close contact and can slide relative to each other.

[0105] When the rock sample is radially sheared, the front and rear ends of the first support body 1 and the second support body 2 are fixedly connected by bolt assemblies 13 to form a lower box body. The upper surface of the first support body 1 is flush with the upper surface of the second support body 2. The front and rear ends of the third support body 3 and the fourth support body 4 are also fixedly connected by bolt assemblies 13 to form an upper box body. The bottom surface of the third support body 3 is flush with the bottom surface of the fourth support body 4. In use, the bottom surface of the upper box body and the upper surface of the lower box body are in close contact and can slide relative to each other.

[0106] The first support body 1 and the second support body 2 each have a lower groove 52 with the same structure on their adjacent sides, and the third support body 3 and the fourth support body 4 each have an upper groove 51 with the same structure on their adjacent sides. The two upper grooves 51 and the two lower grooves 52 form a closed cavity 14 that can accommodate the rock sample.

[0107] Specifically, both the upper groove 51 and the lower groove 52 are square or rectangular cavities. The lower end of the upper groove 51 extends to the bottom surface of the third support 3 or the fourth support 4, and the upper end of the lower groove 52 extends to the upper surface of the first support 1 or the second support 2. The two upper grooves 51 combine to form a square cavity with its opening facing downwards, and the two lower grooves 52 combine to form a square cavity with its opening facing upwards. The two square cavities combine to form the closed cavity 14.

[0108] It is particularly important to note that the inner walls of each of the upper grooves 51 and the lower grooves 52 are coated with a thin-walled rubber coating. The thin-walled rubber coating preferably uses silicone rubber with excellent elasticity. After the four carriers are assembled, the thin-walled rubber coatings located inside the carriers form an encapsulation structure that wraps around the outside of the rock sample. The size of the rock sample is slightly larger than the cavity size of the encapsulation structure. By utilizing the elastic micro-deformation of the thin-walled rubber coating, its surface is tightly attached to the outer surface of the rock sample. Water will only seep through the interior of the rock sample and will not seep along its surface, thus ensuring the accuracy and reliability of the test.

[0109] Furthermore, an annular sealing ring 53 is provided on the outer edge of both the upper groove 51 and the lower groove 52. The annular sealing ring 53 includes two U-shaped segments 532 of the same size, which are located on two mutually perpendicular planes. The two ends of one U-shaped segment 532 are fixedly connected to the two ends of the other U-shaped segment 532 to form a single unit. Each annular sealing ring 53 is fixedly embedded in the two adjacent side walls of the carrier in which its inner groove is located. The corresponding portions of the annular sealing rings 53 located on the adjacent side walls of any two adjacent carriers are staggered.

[0110] For the annular sealing ring 53 on the first carrier 1, one U-shaped segment 532 of the annular sealing ring 53 is located on the upper surface of the first carrier 1, and the other U-shaped segment 532 is located on the right side wall of the first carrier 1. The annular sealing rings 53 on the other carriers are arranged in the same manner. The outer surface of the annular sealing ring 53 is an arc-shaped curved surface, with both sides along its length flush with the outer wall of the carrier on which it is located, and the middle part slightly higher than the outer wall of the carrier. In addition, the annular sealing ring 53 on the first carrier 1 is the same size as the annular sealing ring 53 on the fourth carrier 4, and the annular sealing ring 53 on the second carrier 1 is the same size as the annular sealing ring 53 on the third carrier 2. The size of the annular sealing ring 53 on the first carrier 1 is larger than the size of the annular sealing ring 53 on the fourth carrier 4. After the four carriers are assembled, the annular sealing rings 53 on any two adjacent carriers are pressed together to form a double-layer sealing structure at the interface, which can effectively prevent leakage.

[0111] The lower groove 52 has a set of seepage holes 54 on its sidewall and bottom wall, and the upper groove 51 has a set of seepage holes 54 on its sidewall and top wall. Each set of seepage holes 54 includes three seepage holes 54 arranged linearly and at equal intervals. The three seepage holes 54 on the sidewall of the upper groove 51 or the lower groove 52 are distributed along the centerline of the square plane. That is, the three seepage holes 54 on the sidewall of the first support body 1 are arranged opposite to the three seepage holes 54 on the sidewall of the second support body 1, and the three seepage holes 54 on the sidewall of the third support body 1 are also arranged opposite to the three seepage holes 54 on the sidewall of the fourth support body 1. In addition, the three seepage holes 54 on the top wall of the upper groove 51 and the three seepage holes 54 on the bottom wall of the lower groove 52 are arranged longitudinally and opposite to each other vertically. As a preferred embodiment, the end of the seepage hole 54 adopts a conical structure, and each seepage hole 54 is equipped with a sealing plug. The sealing plug is a rubber plug with an internal rigid skeleton, and the shape of its outer wall is consistent with the shape of the inner wall of the corresponding groove, so as to ensure that the sealing plug will not leak water after sealing the corresponding seepage hole 54.

[0112] Each carrier has two water pipe joints on its front side wall. The two water pipe joints are water pipe joint 1 55 and water pipe joint 2 56. The two water pipe joints on the same carrier are connected to two sets of seepage holes 54 on the carrier through independent water channels 57. The three seepage holes 54 in the same set can be used as both water inlets and water outlets. The connection method between the two water pipe joints and the water supply device can be determined according to the actual use. The water supply device adopts existing technology.

[0113] The third carrier 3 is laterally slidably engaged with the first carrier 1 through a linear guide component 1, and the fourth carrier 4 is laterally slidably engaged with the second carrier 2 through the same linear guide component 1.

[0114] Specifically, a set of limiting grooves 61 is provided on the upper surfaces of the first support body 1 and the second support body 2 on opposite sides. Each set of limiting grooves 61 includes two limiting grooves 61 spaced apart. The limiting grooves 61 have a square cross-section and extend laterally. The first support body 1 and the second support body 2 each have a tunnel cavity 62 with the same number and position as the limiting grooves 61. The tunnel cavity 62 has a dovetail cross-section, extends laterally, and is located on the side of its corresponding limiting groove 61 near the axial shear surface 101. One end of the tunnel cavity 62 communicates with the corresponding limiting groove 61, and the other end extends to the side wall of the support body.

[0115] Both the third support body 3 and the fourth support body 4 are equipped with two linear guide components at their bottoms. Each linear guide component includes a positioning slide 63 and a dovetail guide rail 64. The positioning slide 63 is fixed to the bottom surface of the third support body 3 or the fourth support body 4, and the dovetail guide rail 64 is located inside the positioning slide 63 and slides laterally with it. The cross-section of the positioning slide 63 matches the cross-section of the limiting groove 61, and the cross-section of the dovetail guide rail 64 matches the cross-section of the tunnel cavity 62.

[0116] A square connecting block 65 is fixed to one side of the end of the dovetail guide rail 64. The end face of the positioning slide 63 has a groove 66 that matches the square connecting block 65. The through hole of the square connecting block 65 is equipped with a locking screw. The dovetail guide rail 64 slides relative to the positioning slide 63 until the square connecting block 65 enters the groove 66. The dovetail guide rail 64 and the positioning slide 63 are fixedly connected together by the locking screw.

[0117] During assembly, the fixed connection between the dovetail guide rail 64 and the positioning slide 63 can be released as needed, and the dovetail guide rail 64 can be pulled outward to ensure that the two positioning slides 63 at the bottom of the third carrier 3 are respectively embedded inside the two limiting grooves 61 of the first carrier 1, and the two positioning slides 63 at the bottom of the fourth carrier 4 are respectively embedded inside the two limiting grooves 61 of the second carrier 2. Then, the dovetail guide rail 64 is pushed inward, and one end of the dovetail guide rail 64 enters the corresponding tunnel cavity 62. After it is in place, the other end of the dovetail guide rail 64 is fixedly connected to the positioning slide 63 by locking screws, so that the bottom surfaces of the third carrier 3 and the fourth carrier 4 are respectively in close contact with the upper surfaces of the first carrier 1 and the second carrier 2, ensuring a sealed fit at the shearing surface during radial shearing.

[0118] The fourth carrier 4 is vertically slidably engaged with the third carrier 3 through the second linear guide component, and the second carrier 2 is vertically slidably engaged with the first carrier 1 through the same second linear guide component.

[0119] Specifically, a set of limiting grooves 71 is provided on the side of the right side wall of the first support body 1 and the third support body 3 that are far apart from each other. Each set of limiting grooves 71 includes two limiting grooves 71 arranged one in front of the other. The limiting grooves 71 have a square cross-section and extend vertically. The first support body 1 and the third support body 3 each have a tunnel cavity 72 that is equal in number and corresponds one-to-one with the limiting grooves 71. Each tunnel cavity 72 has a dovetail-shaped cross-section, extends vertically, and is located on the side of its corresponding limiting groove 71 near the radial shear surface 102. The tunnel cavity 72 communicates with the corresponding limiting groove 71.

[0120] Both the second support body 2 and the fourth support body 4 have two linear guide components on their left sides. Each linear guide component includes a positioning slide 73 and a dovetail guide rail 74. The positioning slide 73 is fixed to the left side wall of the second or fourth support body 4, and the dovetail guide rail 74 is located inside the positioning slide 73 and slides vertically with it. The cross-section of the positioning slide 73 matches the cross-section of the limiting groove 71, and the cross-section of the dovetail guide rail 74 matches the cross-section of the tunnel cavity 72.

[0121] A square connecting block 75 is fixed to one side of the end of the dovetail guide rail 2 74. The end face of the positioning slide 2 73 has a countersunk groove 2 76 that matches the square connecting block 2 75. The square connecting block 2 75 has a through hole with the same locking screw. The dovetail guide rail 2 74 can slide relative to the positioning slide 2 73 until the square connecting block 2 75 enters the inside of the countersunk groove 2 76. The dovetail guide rail 2 74 and the positioning slide 2 73 are fixedly connected together by the locking screw.

[0122] During assembly, the fixed connection between the dovetail guide rail 2 74 and the positioning slide 2 73 can be released as needed, and the relative positions of the dovetail guide rail 2 74 and the positioning slide 2 73 can be adjusted to ensure that the two positioning slides 2 73 on the left side of the second carrier 2 are respectively embedded in the two limiting grooves 2 71 of the first carrier 1, and the two positioning slides 2 73 on the left side of the fourth carrier 4 are respectively embedded in the two limiting grooves 2 71 of the third carrier 3. When the positioning slide 2 73 is embedded in the inner side of the corresponding limiting groove 2 71, the dovetail guide rail 2 74 is pushed inward so that one end of the dovetail guide rail 2 74 enters the tunnel cavity 2 72 that communicates with the limiting groove 2 71. Then, the other end of the dovetail guide rail 2 74 is fixedly connected to the positioning slide 2 73, so that the right side walls of the first carrier 1 and the third carrier 3 are respectively close to the right side walls of the second carrier 2 and the fourth carrier 4, ensuring a sealed fit at the shearing surface during axial shearing.

[0123] Example 3, combined with Figures 1 to 11 A method for operating a combined rock sample shear-seepage testing device, based on the combined rock sample shear-seepage testing device described in Example 1 or Example 2, includes the following steps:

[0124] S1. According to the requirements of the experimental design, determine the shear mode and seepage mode for the rock sample. There are two shear modes: radial shear mode and axial shear mode.

[0125] There are three types of seepage: the seepage direction is parallel to the shear direction, the seepage direction is perpendicular to the shear direction, and the seepage direction is relatively inclined to the shear direction.

[0126] According to the requirements of the experimental design, the corresponding rock samples were processed and prepared.

[0127] S2. Based on the seepage method determined in S1, select the seepage hole 54 as the water inlet and the seepage hole 54 as the water outlet, and use a sealing plug to seal all the remaining seepage holes 54.

[0128] If radial shear mode is used (see...) Figure 10 The first support body 1 and the second support body 2 are placed side by side. The rock sample is placed inside the lower groove 52 of the first support body 1 and the second support body 2. Then, the front and rear ends of the first support body 1 and the second support body 2 are fixedly connected to form the lower box body. The lower part of the rock sample is located inside the lower box body.

[0129] Then, the third carrier 3 and the fourth carrier 4 are placed on the left and right sides of the top of the lower box, respectively. The two dovetail guide rails 64 are fixedly connected to the corresponding positioning slides 63. The third carrier 3 and the fourth carrier 4 move horizontally relative to each other to achieve closure. The two dovetail guide rails 64 are located in the tunnel cavity 62 of the first carrier 1 and the second carrier 2, respectively.

[0130] The two dovetail guide rails 74 are pushed vertically into the tunnel cavity 72 of the third carrier 3 and the first carrier 1 respectively, and the two dovetail guide rails 74 are fixedly connected to the corresponding positioning slides 73 respectively. Then, the front and rear ends of the third carrier 3 and the fourth carrier 4 are fixedly connected to form the upper box.

[0131] At this time, the rock sample is encapsulated in the closed cavity 14 of the shear box, and the upper box can slide and seal with the lower box laterally.

[0132] If the axial shear mode is used (see...) Figure 11 The third support 3 and the first support 1 are placed adjacent to each other. The rock sample is placed in the lower groove 52 of the first support 1 and the upper groove 51 of the third support 3. The front and rear ends of the first support 1 and the third support 3 are fixedly connected to form the left box. The left side of the rock sample is located inside the left box.

[0133] Then, the second carrier 2 and the fourth carrier 4 are placed on the right side of the first carrier 1 and the third carrier 3 respectively. The two dovetail guide rails 74 are fixedly connected to the corresponding positioning slides 73 respectively, pushing the second carrier 2 and the fourth carrier 4 to move vertically relative to each other to achieve closing. The two dovetail guide rails 74 are located in the tunnel cavity 72 of the first carrier 1 and the third carrier 3 respectively.

[0134] The two dovetail guide rails 64 are pushed laterally into the tunnel cavity 62 of the first carrier 1 and the second carrier 2 respectively, and the two dovetail guide rails 64 are fixedly connected to the corresponding positioning slides 63 respectively. Then, the second carrier 2 and the fourth carrier 4 are fixedly connected to form the right side box.

[0135] At this time, the rock sample is encapsulated in the closed cavity 14 of the shear box, and the right box can slide and seal vertically with the left box.

[0136] S3. Initialize and adjust the shear loading device; the horizontal loading cylinder 84 of the shear loading device is in the retracted state. Specifically, the shear loading device adopts a loading device already available in the prior art.

[0137] Specifically, the shearing loading device includes a worktable 81, a limiting seat 82, a cylinder support 83, a horizontal loading cylinder 84, and a loading plate 85. The limiting seat 82 is fixedly installed on the left side of the upper surface of the worktable 81, and the horizontal loading cylinder 84 is located to the right of the limiting seat 82. Its cylinder body is fixedly connected to the worktable 81 through the cylinder support 83. In addition, the loading plate 85 is vertically arranged between the horizontal loading cylinder 84 and the limiting seat 82, and the loading plate 85 and the limiting seat 82 are vertically offset. The piston rod end of the horizontal loading cylinder 84 is fixedly connected to the right side wall of the loading plate 85 through a force sensor 86.

[0138] The shearing loading device also includes a vertical loading cylinder 87 and a ball bearing plate 89. The cylinder body of the vertical loading cylinder 87 is fixedly installed above the shear box via a reaction frame 88. The ball bearing plate 89 is horizontally arranged between the shear box and the vertical loading cylinder 87. The piston rod end of the vertical loading cylinder 87 is fixedly connected to the top center of the ball bearing plate 89 via a force sensor 86. The vertical loading cylinder 87 drives the ball bearing plate 89 to rise or fall. According to the experimental design requirements, the vertical loading cylinder can apply a set value of vertical force to the top of the shear box.

[0139] The shear box assembled in radial shear mode is moved to the worktable 81 of the shear loading device, or the shear box assembled in axial shear mode is rotated 90° around the intersection line of the axial shear surface 101 and the radial shear surface 102 and then moved to the worktable 81 of the shear loading device, so that the carrier where the water inlet seepage hole 54 is located is below the carrier where the drainage seepage hole 54 is located.

[0140] S4. Connect the inlet pipe of the water supply device used for the rock seepage experiment to the water pipe joint corresponding to the seepage hole 54 of the inlet, and connect the return pipe of the water supply device to the water pipe joint corresponding to the seepage hole 54 of the outlet. The water supply device adopts the prior art.

[0141] According to the experimental design requirements, firstly, the vertical loading cylinder 86 is started, and the telescopic end of the vertical loading cylinder 86 applies a vertical force to the top of the shear box through the ball plate 55.

[0142] Then, the horizontal loading cylinder 84 is activated. The telescopic end of the horizontal loading cylinder 84 applies a horizontal force to the upper right side of the shear box through the loading plate 85. The limiting seat 82 limits the lower left side of the shear box. At the same time, the water supply device starts to work, supplying water to the closed cavity 14 of the shear box to obtain relevant experimental data.

[0143] Subsequently, according to the experimental design requirements, the horizontal loading cylinder 84 was activated and began to load the outer wall of the shear box. At the same time, the water supply device started working, supplying water to the closed cavity 14 of the shear box to obtain relevant experimental data.

[0144] After the test, the horizontal loading cylinder 84 was restored to its initial state, and the connection between the shear box and the water supply device was disconnected.

[0145] After the rock sample is removed, each support structure is disassembled, and the support structures and the worktable of the shear loading equipment are cleaned.

[0146] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0147] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0148] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A combined rock sample shear-seepage test apparatus, characterized in that, It includes a first carrier, a second carrier, a third carrier, and a fourth carrier. All four carriers are rectangular structures of the same specifications and can be combined to form a cubic shear box. The first and second carriers are arranged adjacent to each other on the left and right. The third and fourth carriers are respectively located directly above the first and second carriers. The third and fourth carriers are arranged adjacent to each other. The front and rear sides of each carrier can be bolted to the corresponding sides of the adjacent carriers. The third carrier is laterally slidably engaged with the first carrier through a linear guide component one; the fourth carrier is laterally slidably engaged with the second carrier through the same linear guide component one; the fourth carrier is vertically slidably engaged with the third carrier through a linear guide component two; and the second carrier is vertically slidably engaged with the first carrier through the same linear guide component two. The right side walls of the first and third bearings and the left side walls of the second and fourth bearings adhere to each other to form an axial shear surface for the rock sample. In addition, the upper surfaces of the first and second bearings and the lower surfaces of the third and fourth bearings adhere to each other to form a radial shear surface for the rock sample. The first and second carriers each have a lower groove on one side of their adjacent sides, and the third and fourth carriers each have an upper groove on one side of their adjacent sides. The two upper grooves and the two lower grooves form a closed cavity that can accommodate the rock sample. The inner walls of the upper and lower grooves are coated with a thin rubber coating. An annular sealing ring is provided on the outer edge of both the upper and lower grooves. Each annular sealing ring is fixed in an embedded manner on two adjacent side walls of the carrier in which the inner groove is located. The corresponding parts of the annular sealing rings on the adjacent side walls of any two adjacent carriers are staggered. The lower groove has a set of seepage holes on its side wall and bottom wall, and the upper groove has a set of seepage holes on its side wall and top wall. Each set of seepage holes includes multiple seepage holes, and each seepage hole is equipped with a sealing plug. Each carrier has two water pipe joints on its front side wall. The two water pipe joints on the same carrier are connected to two sets of seepage holes on the carrier through independent water channels.

2. The combined rock sample shear-seepage test apparatus according to claim 1, characterized in that, The four carriers are arranged horizontally along their length. The front and rear sidewalls of the shear box each have four sets of square grooves, and each set of square grooves includes two square grooves arranged at intervals and opposite to each other. Two of the four sets of square grooves located on the same sidewall are arranged at intervals along the extension direction of the radial shear plane and are located on both sides of the axial shear plane, respectively. The other two sets of square grooves are arranged at intervals along the extension direction of the axial shear plane and are located on both sides of the radial shear plane. The two square grooves in the same group are located on two adjacent bearings, and each adjacent side is close to the radial shear surface or the axial shear surface.

3. The combined rock sample shear-seepage test device according to claim 2, characterized in that, Bolt holes are provided on the adjacent sides of the two square grooves in the same group, and the two bolt holes are coaxial and face each other. Each set of square grooves is equipped with a bolt assembly, which includes a hexagonal bolt and a nut. The hexagonal bolt is inserted into the corresponding bolt hole through one of the square grooves in the same set, and the nut is tightened at the end of the hexagonal bolt through another square groove, so that two adjacent load-bearing bodies are connected into one unit. When the rock sample is subjected to axial shearing, the first and third bearing bodies are fixedly connected to form the left box, and the second and fourth bearing bodies are fixedly connected to form the right box. When the rock sample is subjected to radial shearing, the first and second support bodies are fixedly connected to form the lower box, and the third and fourth support bodies are fixedly connected to form the upper box.

4. The combined rock sample shear-seepage test apparatus according to claim 1, characterized in that, Both the upper and lower grooves are semi-cylindrical structures. The upper end of the lower groove extends to the upper surface of the first or second support body, and the lower end of the upper groove extends to the bottom surface of the third or fourth support body. The two upper grooves combine to form a cylindrical cavity with its opening facing downwards, the two lower grooves combine to form a cylindrical cavity with its opening facing upwards, and the two cylindrical cavities combine to form the closed cavity. The annular sealing ring includes a semi-circular arc section and a U-shaped section. The semi-circular arc section and the U-shaped section are located on two mutually perpendicular planes. The two ends of the U-shaped section are fixedly connected to the two ends of the semi-circular arc section to form a whole.

5. The combined rock sample shear-seepage test apparatus according to claim 1, characterized in that, Both the upper and lower grooves are square structures. The lower end of the upper groove extends to the bottom surface of the third or fourth support body, and the upper end of the lower groove extends to the upper surface of the first or second support body. The two upper grooves combine to form a square cavity with its opening facing downwards, the two lower grooves combine to form a square cavity with its opening facing upwards, and the two square cavities combine to form the closed cavity. The annular sealing ring includes two U-shaped sections of the same size, which are located on two mutually perpendicular planes. The two ends of one U-shaped section are fixedly connected to the two ends of the other U-shaped section to form a whole.

6. The combined rock sample shear-seepage test apparatus according to claim 1, characterized in that, The upper surfaces of the first and second carriers are provided with a set of limiting grooves on the side that is far apart from each other. Each set of limiting grooves includes two limiting grooves distributed at intervals. The first and second carriers each have a tunnel cavity I with the same number and position as the limiting groove I. Each tunnel cavity I extends laterally and is located on the side of its corresponding limiting groove I near the axial shear surface. The tunnel cavity I communicates with the corresponding limiting groove I.

7. A combined rock sample shear-seepage test apparatus according to claim 6, characterized in that, The bottom of the third and fourth carriers is provided with two linear guide components. The linear guide component includes a positioning slide and a dovetail guide rail. The positioning slide is fixed to the bottom surface of the third or fourth carrier, and the dovetail guide rail is located inside the positioning slide and slides laterally with it. The two positioning slides at the bottom of the third carrier are respectively embedded in the two limiting grooves of the first carrier, and the two positioning slides at the bottom of the fourth carrier are respectively embedded in the two limiting grooves of the second carrier. When the positioning slide is embedded in the inner side of the corresponding limiting groove, one end of the dovetail guide rail on its inner side passes into the tunnel cavity communicating with the limiting groove, and the other end of the dovetail guide rail is detachably and fixedly connected to the positioning slide.

8. The combined rock sample shear-seepage test apparatus according to claim 1, characterized in that, On the side of the right side wall of the first and third bearings that are far apart from each other, there is a set of limiting grooves II. Each set of limiting grooves II includes two limiting grooves II arranged one in front of the other. The first and third carriers each have a tunnel cavity two that is equal in number and corresponding in position to the limiting groove two. Each tunnel cavity two extends vertically and is located on the side of its corresponding limiting groove two near the radial shear surface. The tunnel cavity two communicates with the corresponding limiting groove two.

9. A combined rock sample shear-seepage test apparatus according to claim 8, characterized in that, The second and fourth carriers are each provided with two linear guide components 2 on their left sides. The linear guide components 2 include a positioning slide 2 and a dovetail guide rail 2. The positioning slide 2 is fixed on the left side wall of the second or fourth carrier, and the dovetail guide rail 2 is located inside the positioning slide 2 and slides vertically with it. The two positioning slides on the left side of the second carrier are respectively embedded in the two limiting grooves of the first carrier, and the two positioning slides on the left side of the fourth carrier are respectively embedded in the two limiting grooves of the third carrier. When the positioning slide 2 is embedded inside the corresponding limiting groove 2, one end of the dovetail guide rail 2 inside it passes into the tunnel cavity 2 that communicates with the limiting groove 2, and the other end of the dovetail guide rail 2 is detachably and fixedly connected to the positioning slide 2.

10. A method for operating a combined rock sample shear-seepage testing device as described in any one of claims 1-9, comprising the following steps: S1. According to the requirements of the experimental design, determine the shear mode and seepage mode for the rock sample. There are two shear modes: radial shear mode and axial shear mode. There are three types of seepage: the seepage direction is parallel to the shear direction, the seepage direction is perpendicular to the shear direction, and the seepage direction is relatively inclined to the shear direction. According to the requirements of the experimental design, prepare the corresponding rock samples; S2. Based on the seepage method determined in S1, select the seepage holes as the inlet and the seepage holes as the outlet, and seal all the remaining seepage holes with sealing plugs. If the radial shear mode is adopted, the first and second carriers are placed side by side, the rock sample is placed in the lower groove of the first and second carriers, and the first and second carriers are fixedly connected to form the lower box. Next, place the third and fourth carriers on the left and right sides of the top of the lower box, respectively, and push the third and fourth carriers to move horizontally relative to each other to achieve closure. Then, fix the front and rear ends of the third and fourth carriers together to form the upper box. At this time, the rock sample is encapsulated in the closed cavity of the shear box, and the upper box can slide and seal with the lower box laterally. If the axial shear mode is adopted, the third support body and the first support body are placed adjacent to each other, the rock sample is placed in the lower groove of the first support body and the upper groove of the third support body, and the first and third support bodies are fixedly connected to form the left box body; Then, the second and fourth carriers are placed to the right of the first and third carriers respectively, and the second and fourth carriers are pushed to move vertically relative to each other to achieve closure. Then, the second and fourth carriers are fixedly connected to form the right side box. At this time, the rock sample is encapsulated in the closed cavity of the shear box, and the right box can slide and seal vertically with the left box. S3. Initialize the shear loading device. Both the vertical loading cylinder and the horizontal loading cylinder of the shear loading device are in the retracted state. The shear box assembled in radial shear mode is moved to the worktable of the shear loading device, or the shear box assembled in axial shear mode is rotated 90° around the intersection line of the axial shear plane and the radial shear plane and then moved to the worktable of the shear loading device, so that the carrier where the water inlet seepage hole is located is below the carrier where the drainage seepage hole is located. S4. Connect the inlet pipe of the water supply device used for the rock seepage experiment to the water pipe joint corresponding to the seepage hole of the inlet water, and connect the return pipe of the water supply device to the water pipe joint corresponding to the seepage hole of the outlet water. According to the experimental design requirements, firstly, the vertical loading cylinder is started, and the telescopic end of the vertical loading cylinder applies a vertical force to the top of the shear box through the ball plate; Afterwards, the horizontal loading cylinder is activated. The telescopic end of the horizontal loading cylinder applies a horizontal force to the outer wall of the shear box through the loading plate. At the same time, the water supply device starts working, supplying water to the closed cavity of the shear box to obtain relevant experimental data. After the test, both the vertical loading cylinder and the horizontal loading cylinder were returned to their initial state, and the connection between the shear box and the water supply device was disconnected. Afterwards, the rock samples were removed, the various support structures were disassembled, and the worktable of each support structure and the shear loading equipment was cleaned.

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