A True Triaxial Creep Disturbance Loading Test System under Stress-Flow Coupling

Abstract

The application discloses a stress-seepage coupling true triaxial creep disturbance loading test system, which comprises a test main machine, a hydraulic station, a power distribution cabinet, a water supply device and an industrial computer. The test main machine comprises a workbench, a confining pressure chamber, a vertical loading unit, a transverse loading unit, a longitudinal loading unit, a lifting device and an in-out material platform. A main frame is arranged on the top of the workbench, and the confining pressure chamber is arranged on the inner side of the main frame. The vertical loading unit comprises an impact load oil cylinder, a top loading oil cylinder, a top loading head and an impact load transmission rod. The transverse loading unit comprises a left side loading oil cylinder, a right side loading oil cylinder, a left loading head and a right loading head. The longitudinal loading unit comprises a front side loading oil cylinder, a rear side loading oil cylinder, a front loading head and a rear loading head. The application can be used for long time loading under a multi-dimensional stress environment, and can introduce seepage effect and dynamic disturbance, so that the real stress and seepage state of a waste mine roadway under the condition of water pumping and storage can be simulated, and theoretical and experimental basis can be provided for the water pumping and storage application of the waste mine.

Description

Technical Field

[0001] This invention relates to the field of rock mechanics engineering technology, specifically to a true triaxial creep disturbance loading test system under stress-seepage coupling. Background Technology

[0002] With the development of the mining industry, a large number of mines have been abandoned after resources have been depleted. How to rationally develop and utilize these abandoned mines has become a crucial issue in resource recycling and environmental protection. In recent years, pumped storage in abandoned mines has emerged as a new green energy storage method. By transforming mine spaces into energy storage facilities, not only can abandoned resources be fully utilized, but the peak-valley load differences in the power system can also be effectively alleviated, providing a new solution for the storage and peak-shaving of new energy sources. However, the application of pumped storage in abandoned mine tunnels involves complex geological conditions and engineering challenges, particularly the long-term stability of rock masses under high water pressure and complex stress environments.

[0003] Traditional testing equipment struggles to simultaneously simulate multidimensional stresses, seepage conditions, and long-term creep effects within mine tunnels, thus failing to accurately reproduce the actual stress state of mine tunnels during pumped-storage processes. Existing triaxial testing equipment is primarily suitable for loading under single stress or single seepage environments, lacking methods for studying the long-term mechanical behavior of rocks under the coupled effects of multiple factors. Therefore, existing technologies urgently require further improvement and refinement. Summary of the Invention

[0004] To address the shortcomings of the existing technology, one objective of this invention is to propose a true triaxial creep disturbance loading test system under stress-seepage coupling, which solves the problem that existing test devices are unable to simultaneously simulate multidimensional stress, seepage conditions and long-term creep effects in roadways, and are unable to realistically reproduce the actual stress state of mine roadway rock mass during pumping and energy storage.

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

[0006] A true triaxial creep disturbance loading test system under stress-seepage coupling includes a test host, a hydraulic station, a power distribution cabinet, a water supply device, a gantry crane, and an industrial control computer. The test host includes a workbench, a host frame, a confining pressure chamber, a vertical loading unit, a horizontal loading unit, a longitudinal loading unit, a lifting device, and a feeding and discharging platform. The host frame is an N-shaped steel frame structure that runs through the front and back and is fixed above the workbench.

[0007] The feeding and discharging platform is fixedly installed on the front side of the workbench, the lifting device is installed on the upper front side of the main frame, and the confining pressure chamber is set on the workbench through a liftable linear transfer mechanism.

[0008] The vertical loading unit includes an impact load cylinder, a top loading cylinder, a top loading head, and an impact transmission rod. The impact load cylinder is vertically positioned at the top center of the main frame. There are multiple top loading cylinders, all of which are regularly arranged around the impact load cylinder. The actuators of each top loading cylinder are fixedly connected by force-collecting blocks.

[0009] The top loading head is set on the upper side of the confining chamber via a vertical loading rod. Inside the vertical loading rod is an impact transmission rod arranged coaxially with it. The force-gathering block applies a static load to the top loading head via the vertical loading rod, and the impact load cylinder applies an impact load to the top loading head via the impact transmission rod.

[0010] The lateral loading unit includes a left loading cylinder, a right loading cylinder, a left loading head, and a right loading head. The left and right loading heads are both positioned opposite each other inside the confining chamber via a lateral loading rod. The left and right loading cylinders are symmetrically installed on the left and right sides of the main frame, applying static loads to the left and right loading heads synchronously, respectively.

[0011] The longitudinal loading unit includes a front loading cylinder, a rear loading cylinder, a front loading head, and a rear loading head. The front loading head and the rear loading head are both set opposite each other inside the confining chamber via a longitudinal loading rod. The front loading cylinder and the rear loading cylinder are both symmetrically set on the front and rear sides of the main frame via a rotating arm, and apply static loads to the front loading head and the rear loading head synchronously, respectively.

[0012] A square groove is provided on the end face of the front loading head, and a water channel is provided inside the longitudinal loading rod connected to the front loading head. The water supply device supplies high-pressure water into the square groove through the water channel.

[0013] Furthermore, two robotic arms are symmetrically arranged on the lower part of the front and rear sides of the main frame, and two hinge supports are symmetrically arranged on the rear side wall of the main frame. The left and right ends of the rear robotic arms are detachably and fixedly connected to the two hinge supports respectively.

[0014] The front side wall of the main frame has two symmetrical hinge supports. The left end of the front robotic arm is hinged to the left hinge support. A pin cylinder is provided below the hinge support. The pin cylinder is fixedly connected to the right side of the main frame through a cylinder bracket. The pin cylinder locks and fixes the right end of the front robotic arm to the right hinge support.

[0015] Furthermore, the rear end of the feeding / discharging platform is fixedly connected to the workbench, and its upper surface is flush with the surface of the workbench. The upper surface of the workbench is provided with two straight grooves symmetrically arranged on the left and right sides, and the two straight grooves extend to the front end of the feeding / discharging platform. A positioning hole is provided in the middle of the workbench.

[0016] The linear transfer mechanism includes a square base plate, positioning columns, and four stroke cylinders. The four stroke cylinders are respectively installed on the upper surface of the four corners of the square base plate. The bottom of the square base plate has a storage groove that is equal in number and corresponds to the position of the stroke cylinders. Each storage groove has a roller embedded in it. Each roller is fixedly installed on the piston rod end of the corresponding stroke cylinder above it. The two rollers on the same side are matched with the linear groove on the corresponding side.

[0017] The positioning post is vertically fixed to the center of the bottom of the square base plate, and its lower end can be inserted into the positioning hole to fix the square base plate to the workbench.

[0018] Furthermore, the confining chamber includes a base, a cylindrical body, and a top cover. The base is fixed to the upper surface of the linear transfer mechanism and has a frustum-shaped structure. The cylindrical body is a cylindrical structure with openings at both ends and is vertically positioned above the base. The upper end of the cylindrical body is fixedly and sealed to the top cover, and the lower end of the cylindrical body is sealed to the base and fixedly connected to the base through a clamping assembly.

[0019] The lifting device includes a lifting cylinder and a lifting rod. The cylinder body of the lifting cylinder is fixedly connected to the front side of the crossbeam of the main frame through a cylinder bracket. The lifting rod is arranged vertically, with its upper end fixedly connected to the piston rod end of the lifting cylinder and its lower end fixed with a connecting plate. The connecting plate is equipped with connecting bolts that can be fixedly connected to the top cover bolts.

[0020] Furthermore, the upper surface of the base has a circular boss, and at least two sealing rings are embedded on the side wall of the circular boss. All the sealing rings are arranged at intervals along the axial direction of the base. The lower end of the cylinder is sleeved on the outside of the circular boss and is sealed with the circumferential side wall of the circular boss.

[0021] The lower end of the cylinder has an annular protrusion 1 on the outer side wall, and the upper part of the outer side wall of the base has an annular protrusion 2. The outer diameter of the annular protrusion 1 and the outer diameter of the annular protrusion 2 are equal.

[0022] The clamping assembly includes four clips and a clamp. Each clip is a quarter-circular arc with a groove on the inner side. The four clips are joined together to form a ring, which is clamped at the connection between the base and the lower end of the cylinder. The clamp is fitted over the four clips to fix the lower end of the cylinder to the base.

[0023] Furthermore, each of the top loading cylinder, left loading cylinder, right loading cylinder, front loading cylinder, and rear loading cylinder is equipped with an axial displacement sensor, and the impact load cylinder is equipped with an impact displacement sensor. Each displacement sensor is connected to the industrial control computer for communication. The impact load cylinder and each loading cylinder are supplied with and returned oil by a hydraulic station.

[0024] Furthermore, a vertical external loading head is provided at the bottom center of the force-gathering block, and an impact loading rod is provided at the end of the piston rod of the impact load cylinder. The lower end of the impact loading rod passes through the vertical external loading head and is inserted into the upper end of the impact force transmission rod. The upper end of the vertical loading rod is inserted into the bottom of the vertical external loading head.

[0025] Furthermore, both the left and right loading cylinders have a transverse force transmission rod at the piston rod end. The two transverse force transmission rods are arranged coaxially opposite each other and slide in cooperation with the main frame along its axial direction. Each of the corresponding ends of the two transverse force transmission rods has a transverse external loading head.

[0026] Both the front and rear loading cylinders have a longitudinal force transmission rod at the piston rod end. The two longitudinal force transmission rods are arranged coaxially opposite each other and are slidably engaged with the corresponding robotic arms along their axial direction. The corresponding ends of the two longitudinal force transmission rods are also provided with a longitudinal external loading head.

[0027] Each external loading head is equipped with a force sensor, and each force sensor is connected to the industrial control computer.

[0028] Furthermore, the two transverse loading rods are coaxially opposite to each other on the side wall of the confining pressure chamber, and the two longitudinal loading rods are coaxially opposite to each other on the side wall of the confining pressure chamber. Both the transverse and longitudinal loading rods slide and seal against the side wall of the confining pressure chamber along their axial direction, and the axes of the transverse and longitudinal loading rods are at the same height.

[0029] The left and right loading heads are fixedly connected to the opposite ends of two transverse loading rods on opposite sides, and the front and rear loading heads are fixedly connected to the opposite ends of two longitudinal loading rods on opposite sides. Each transverse and longitudinal loading rod is located at one end outside the confining pressure chamber and is inserted into the corresponding external loading head.

[0030] Each transverse loading rod and each longitudinal loading rod is fitted with a return spring. All return springs are located on the outside of the confining chamber. Both the transverse and longitudinal loading rods are provided with annular limiting parts to limit the return springs.

[0031] Furthermore, the square groove is located on the rear end face of the front loading head, the outlet end of the water channel is located at the bottom of the square groove, and the inlet end of the water channel is located on the circumferential surface of the longitudinal loading rod in which it is located, and is connected to the water supply device through a high-pressure pipeline.

[0032] A water pressure sensor, a temperature sensor, and an acoustic emission sensor are embedded in the square groove on the rear end face of the front loading head. In addition, the same acoustic emission sensor is provided on the front end face of the rear loading head, the adjacent end faces of the left loading head, and the right loading head.

[0033] Each of the four outer walls of the confining pressure chamber has a set of signal interfaces on its front, rear, left, and right sides. Each set of signal interfaces is electrically connected to a sensor in the loading head at the corresponding position inside the confining pressure chamber.

[0034] By adopting the above technical solution, the beneficial technical effects of this invention are as follows: This invention controls the water pressure in the square groove of the front loading head to perform seepage operation on one side of the sample, controls the output pressure of the combined loading head on the sample, and simultaneously controls the top loading head to apply impact load to the sample, enabling true triaxial loading tests of rock samples under dynamic-static load-seepage coupling conditions. Real-time monitoring of rock fracture damage data of the loaded sample is achieved using acoustic emission monitoring, real-time monitoring of water pressure data in the confining pressure chamber, real-time monitoring of rock temperature data of the sample using a temperature monitoring sensor, and real-time monitoring of deformation data of the sample using a displacement sensor. This allows for damage evolution analysis during rock fracture, providing important parameters for breakthroughs in rock mechanics theory under dynamic-static-seepage coupling and for guiding on-site tunnel construction. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the structure of the true triaxial creep disturbance loading test system under stress-flow coupling of the present invention.

[0036] Figure 2 This is a three-dimensional structural diagram of the experimental host of the present invention.

[0037] Figure 3 This is the front view of the test host of the present invention.

[0038] Figure 4 This is a top view of the test host of the present invention.

[0039] Figure 5 This is a vertical cross-sectional view of the test host of the present invention.

[0040] Figure 6 This is a perspective view of the combined structure of the confining pressure chamber and related parts of the present invention.

[0041] Figure 7 yes Figure 6 The front view of the composite structure is shown in the figure.

[0042] Figure 8 yes Figure 6 The image shows a top view of the combined structure.

[0043] Figure 9 yes Figure 6 The image shows a vertical cross-sectional view of the composite structure. Detailed Implementation

[0044] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0045] Combination Figures 1 to 9 A true triaxial creep disturbance loading test system under stress-seepage coupling includes a test host, a hydraulic station 101, a power distribution cabinet 102, a water supply device 103, a gantry crane 105, and an industrial control computer 104. The test host includes a workbench 1, a host frame 2, a confining pressure chamber 3, a vertical loading unit, a horizontal loading unit, a longitudinal loading unit, a lifting device, and a feeding and discharging platform 11. The host frame 2 is an N-shaped steel frame structure that runs through the front and back and is fixed above the workbench 1.

[0046] Two robotic arms 23 are symmetrically arranged on the lower part of the front and rear sides of the main frame 2. Two symmetrical hinge supports 21 are located on the rear side wall of the main frame 2. The left and right ends of the rear robotic arms 23 are detachably and fixedly connected to the two hinge supports 21 respectively. Two symmetrical hinge supports 22 are located on the front side wall of the main frame 2. The left end of the front robotic arm 23 is hinged to the left hinge support 22. A pin cylinder 24 is located below the hinge support 22. The pin cylinder 24 is fixedly connected to the right side of the main frame 2 via a cylinder bracket 25, locking the right end of the front robotic arm 23 to the right hinge support 22.

[0047] The feeding / discharging platform 11 is fixedly installed on the front side of the workbench 1. Specifically, the rear end of the feeding / discharging platform 11 is fixedly connected to the workbench 1, and two support legs 13 are installed on the bottom front side of the feeding / discharging platform 11. The upper surface of the feeding / discharging platform 11 is flush with the surface of the workbench 1. Two straight grooves 111 are symmetrically arranged on the upper surface of the workbench 1, and the two straight grooves 111 extend to the front end of the feeding / discharging platform 11. A positioning hole 12 is opened in the middle of the workbench 1.

[0048] The confining chamber 3 is mounted on the workbench 1 via a liftable linear transfer mechanism. Specifically, the confining chamber 3 includes a base 31, a cylindrical body 32, and a top cover 33. The base 31 is fixed to the upper surface of the linear transfer mechanism and has a frustum-shaped structure. The cylindrical body 32 is a cylindrical structure with openings at both ends and is vertically mounted above the base 31. The upper end of the cylindrical body 32 is fixedly and sealed to the top cover 33, and the lower end of the cylindrical body 32 is sealed to the base 31 and fixedly connected to the base 31 via a clamping assembly.

[0049] The upper surface of the base 31 has a circular boss 311. Two sealing rings 312 are fixedly embedded in the side wall of the circular boss 311. The two sealing rings 312 are arranged at intervals along the axial direction of the base 31. The lower end of the cylinder 32 is sleeved on the outside of the circular boss 311 and is sealed with the circumferential side wall of the circular boss 311. The confining pressure chamber 3 is connected to the water supply device 103 through a pipeline. After the confining pressure chamber 3 is filled with high-pressure water, the sample 9 can simulate a uniaxial loading test under dynamic and static confining pressure.

[0050] The lower end of the cylinder 32 has an annular protrusion 321 on its outer side wall, and the upper part of the outer side wall of the base 31 has an annular protrusion 313. The outer diameter of the annular protrusion 321 and the outer diameter of the annular protrusion 313 are equal. The clamping assembly includes four locking flaps 34 and four locking flaps 35. Each locking flap 34 is a quarter-circular arc with a groove on its inner side. The four locking flaps 34 are spliced ​​together to form a ring, which is clamped at the connection between the base 31 and the lower end of the cylinder 32. The clamp 35 is fitted over the four locking flaps 34. The clamping force of the clamp 35 tightens the four locking flaps 34, fixing the lower end of the cylinder 32 to the base 31.

[0051] The linear transfer mechanism includes a square base plate 41, a positioning column 42, and four stroke cylinders 43. The four stroke cylinders 43 are respectively installed on the upper surface of the four corners of the square base plate 41. The bottom of the square base plate 41 has a storage groove with the same number and position as the stroke cylinders 43. Each storage groove is embedded with a roller. Each roller is fixedly installed on the piston rod end of the corresponding stroke cylinder 43 above it. The two rollers on the same side are matched with the linear groove 111 on the corresponding side.

[0052] The positioning post 42 is vertically fixed to the center of the bottom of the square base plate 41, and its lower end can be inserted into the positioning hole 12, so that the square base plate 41 is fixedly connected to the worktable 1. After the sample 9 is placed inside the confining pressure chamber 3, the square base plate 41 is pushed to move backward along the straight groove 111 to the inside of the main frame 2. After reaching the position, the positioning post 42 is aligned with the positioning hole 12 of the worktable 1. The four stroke cylinders 43 drive the four rollers to be stored inside the square base plate 41. The square base plate 41 descends until its bottom is in contact with the surface of the worktable 1. The positioning post 42 is located in the positioning hole 12 of the worktable 1, and the square base plate 41 is fixed on the worktable 1.

[0053] The lifting device is installed on the upper front side of the main frame 2. The lifting device includes a lifting cylinder 44 and a lifting rod 45. The cylinder body of the lifting cylinder 44 is fixedly connected to the front side of the crossbeam of the main frame 2 through a cylinder bracket 46. The lifting rod 45 is arranged vertically. The upper end of the lifting rod 45 is fixedly connected to the piston rod end of the lifting cylinder 44, and the lower end is fixed with a connecting plate 47. The connecting plate 47 is equipped with connecting bolts, which can be bolted to the top cover 33. After lifting the cylinder body 32 and the top cover 33 upwards and separating them from the base 31, the sample 9 is placed on the surface of the circular boss 311 of the base 31. Then, the lifting cylinder 44 lowers the cylinder body 32 and the top cover 33, and the lower end of the cylinder body 32 is fitted with the circular boss 311. Then, the base 31 is fixedly connected to the lower end of the cylinder body 32 through four clips 34 and clamps 35, thus sealing the sample 9 in the confining pressure chamber.

[0054] The vertical loading unit includes an impact load cylinder 51, a top loading cylinder 52, a top loading head 53, and an impact transmission rod 54. The impact load cylinder 51 is vertically fixedly installed at the center of the top of the main frame 2. There are four top loading cylinders 52, which are vertically and regularly arranged around the impact load cylinder 51. Both the impact load cylinder 51 and the top loading cylinder 52 are supplied with oil and returned by the hydraulic station 101.

[0055] The impact load cylinder 51 is equipped with an impact displacement sensor 511, a filter 512 and a high-frequency servo valve 513. Each top loading cylinder 52 is equipped with an axial displacement sensor 521. The impact displacement sensor 511 and each axial displacement sensor 521 are respectively connected to the industrial control computer 104 for communication. Each displacement sensor monitors the deformation data of the sample 9 in the three axial directions in real time.

[0056] The actuators of the four top loading cylinders 52 are fixedly connected together by a force-gathering block 55 located below the crossbeam of the main frame 2. A vertical external loading head 57 is fixedly installed at the bottom center of the force-gathering block 55. The piston rods of the four top loading cylinders 52 extend and retract synchronously, driving the force-gathering block 55 and the external loading head located at the bottom of the force-gathering block 55 to rise or fall.

[0057] The top loading head 53 is installed on the upper part of the inner side of the confining pressure chamber 3 via a vertical loading rod 56. The vertical loading rod 56 has an impact transmission rod 54 arranged coaxially with it. The impact transmission rod 54 slides with the vertical loading rod 56 outside it. The force-gathering block 55 applies a static load to the top loading head 53 via the vertical loading rod 56. The impact load cylinder 51 applies an impact load to the top loading head 53 via the impact transmission rod 54. In turn, the top loading head 53 applies a vertical static load to the sample 9, and the impact transmission rod 54 applies a vertical impact load to the sample 9 via the top loading head 53.

[0058] Specifically, the piston rod end of the impact load cylinder 51 has an impact loading rod 58 coaxially fixedly connected to it. The lower end of the impact loading rod 58 passes through the vertical external loading head 57 and is inserted into the upper end of the impact force transmission rod 54. The impact loading rod 58 passes through the inner side of the vertical external loading head 57 and slides vertically with it. The upper end of the vertical loading rod 56 is inserted into the vertical external loading head 57 at the bottom of the force gathering block 55. The impact load cylinder 51 drives the impact loading rod 58 to rise and fall, applying an impact force to the impact force transmission rod 54 and transmitting it to the top loading head 53.

[0059] The lateral loading unit includes a left loading cylinder 61, a right loading cylinder 62, a left loading head, and a right loading head. The left loading cylinder 61 and the right loading cylinder 62 are symmetrically fixed on the left and right sides of the main frame 2. The left loading cylinder 61 and the right loading cylinder 62 are respectively equipped with the same axial displacement sensor 521. The left loading cylinder 61 and the right loading cylinder 62 are supplied with oil and returned by the hydraulic station 101.

[0060] Both the left-side loading cylinder 61 and the right-side loading cylinder 62 have a transverse force transmission rod at their piston rod ends. These two transverse force transmission rods are coaxially arranged opposite each other and are slidably fitted to the main frame 2 along its axial direction. Each corresponding end of the two transverse force transmission rods has a transverse external loading head 66. These two transverse external loading heads 66 are symmetrically arranged and fixedly connected to the ends of the transverse force transmission rods on the same side. The left-side loading cylinder 61 and the right-side loading cylinder 62 simultaneously apply static loads to the left and right loading heads respectively through the two transverse external loading heads 66 located at the ends of the transverse force transmission rods.

[0061] Both the left and right loading heads are positioned opposite each other inside the confining pressure chamber 3 via a transverse loading rod 67. Specifically, the two transverse loading rods 67 are coaxially aligned and pass through the left and right side walls of the confining pressure chamber 3, with each transverse loading rod 67 slidingly engaging with the side wall of the confining pressure chamber 3 along its axial direction. The opposite sides of the left and right loading heads are fixedly connected to the opposite ends of the two transverse loading rods 67, respectively. The ends of the two transverse loading rods 67 located outside the confining pressure chamber 3 are respectively inserted into the two transverse external loading heads 66 at the ends of the transverse force transmission rods. The left loading cylinder 61 and the right loading cylinder 62 drive the two transverse external loading heads 66 to move synchronously relative to each other, thereby applying transverse loading to the sample 9 by driving the left and right loading heads to move synchronously relative to each other via the transverse loading rods 67.

[0062] The longitudinal loading unit includes a front loading cylinder 71, a rear loading cylinder 72, a front loading head 73, and a rear loading head 74. The front loading cylinder 71 and the rear loading cylinder 72 are symmetrically arranged on the front and rear sides of the main frame 2 via the aforementioned rotating arms. The front loading cylinder 71 and the rear loading cylinder 72 are both equipped with the same axial displacement sensor 521. In addition, the front loading cylinder 71 and the rear loading cylinder 72 are supplied with oil and returned by the hydraulic station 101.

[0063] Both the front loading cylinder 71 and the rear loading cylinder 72 have a longitudinal force transmission rod 75 at their piston rod ends. The two longitudinal force transmission rods 75 are arranged coaxially opposite each other and are slidably engaged with the corresponding robotic arms 23 along their axial direction. Each of the corresponding ends of the two longitudinal force transmission rods 75 has a longitudinal external loading head 76. The left loading cylinder 61 and the right loading cylinder 62 apply static loads synchronously to the front loading head 73 and the rear loading head 74 through the two longitudinal external loading heads 76 located on the longitudinal force transmission rods 75.

[0064] Both the front loading head 73 and the rear loading head 74 are positioned opposite each other inside the confining pressure chamber 3 via a longitudinal loading rod 77. Specifically, the two longitudinal loading rods 77 are coaxially aligned and pass through the front and rear side walls of the confining pressure chamber 3, respectively. The longitudinal loading rods 77 slide against the side walls of the confining pressure chamber 3 along their axial direction, and the axis of the transverse loading rod 67 is at the same height as the axis of the longitudinal loading rod 77. The opposite sides of the front loading head 73 and the rear loading head 74 are fixedly connected to the opposite ends of the two longitudinal loading rods 77. The ends of the two longitudinal loading rods 77 located outside the confining pressure chamber 3 are respectively inserted into the two longitudinal external loading heads 76 at the ends of the longitudinal force transmission rod 75. The front loading cylinder 71 and the rear loading cylinder 72 drive the two longitudinal external loading heads 76 to move synchronously relative to each other, thereby driving the front loading head 73 and the rear loading head 74 to move synchronously and apply longitudinal loading to the sample 9 via the longitudinal loading rods 77.

[0065] Each of the two transverse loading rods 67 and the two longitudinal loading rods 77 is fitted with a return spring 81. All return springs 81 are located on the outside of the confining pressure chamber 3. Both the transverse loading rods 67 and the longitudinal loading rods 77 are provided with annular limiting parts 82 to limit the return springs 81. In the unloaded state, the return springs 81 drive the corresponding transverse loading rods 67 or longitudinal loading rods 77 to move outward, causing the left loading head, right loading head, front loading head 73, and rear loading head 74 to separate from the sample 9. Before placing the sample 9 inside the confining pressure chamber 3, the left loading head, right loading head, front loading head 73, and rear loading head 74 are in an outward-expanding state, which facilitates the placement of the sample 9 into the confining pressure chamber 3. The sample 9 of the present invention is a square specimen or a cylindrical specimen. The square specimen is suitable for true triaxial tests under dynamic and static load seepage coupling, while the cylindrical specimen is suitable for uniaxial tests under dynamic and static load confining pressure.

[0066] A square groove 731 is formed on the end face of the front loading head 73. A water channel 78 is provided inside the longitudinal loading rod 77 connected to the front loading head 73. The water supply device 103 supplies high-pressure water into the square groove 731 through the water channel 78. Specifically, the square groove 731 is located on the rear end face of the front loading head 73. The outlet end of the water channel 78 is located at the bottom of the square groove 731, and the inlet end 781 of the water channel 78 is located on the circumferential surface of the longitudinal loading rod 77. It is connected to the water supply device 103 through a high-pressure pipeline. Under three-dimensional stress loading, the water supply device 103 supplies water to the square groove 731 through the water channel 78 and adjusts the water pressure inside the square groove 731.

[0067] A water pressure sensor, a temperature sensor, and an acoustic emission sensor are embedded in the square groove 731 on the rear end face of the front loading head 73. The water pressure sensor monitors the pressure of the water inside the square groove 731 on the side wall of the sample 9 in real time, and the temperature sensor monitors the temperature of the high-pressure water inside the square groove 731. In addition, the same acoustic emission sensor is provided on the front end face of the rear loading head 74 and the adjacent end faces of the left and right loading heads. The acoustic emission sensor is electrically connected to the acoustic emission detector via a data cable. The acoustic emission sensor monitors and collects the rock fracture damage data of the sample 9 under water pressure, three-dimensional stress loading, and dynamic disturbance. A set of signal interfaces 36 is provided on the front, rear, left, and right sides of the outer circumference of the confining pressure chamber 3. Each set of signal interfaces 36 is electrically connected to the sensor in the corresponding loading head inside the confining pressure chamber 3. The water pressure sensor, temperature sensor, and acoustic emission sensor are connected to the corresponding external devices through the signal interfaces 36.

[0068] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the mechanism or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0069] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0070] 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 stress-seepage coupling true triaxial creep disturbance loading test system, comprising a test host, a hydraulic station, a power distribution cabinet, a water supply device, a gantry crane and an industrial computer, characterized in that, The test main machine comprises a workbench, a main frame, a confining pressure chamber, a vertical loading unit, a transverse loading unit, a longitudinal loading unit, a lifting device and an in-out material platform, the main frame is an N-shaped steel frame structure penetrating through front and back and is fixed above the workbench, the in-out material platform is fixedly arranged on the front side of the workbench, the lifting device is installed on the upper part of the front side of the main frame, and the confining pressure chamber is arranged on the workbench through a liftable linear transfer mechanism; The vertical loading unit comprises an impact load oil cylinder, top loading oil cylinders, a top loading head and an impact force transmission rod, the impact load oil cylinder is vertically arranged at the top center of the main frame, the top loading oil cylinders are multiple, and all the top loading oil cylinders are regularly arranged around the impact load oil cylinder, and the execution ends of the top loading oil cylinders are fixedly connected through a force collecting block; The top loading head is arranged on the upper part of the inner side of the confining pressure chamber through a vertical loading rod, the vertical loading rod has the impact force transmission rod coaxially arranged in the vertical loading rod, the force collecting block applies static load to the top loading head through the vertical loading rod, and the impact load oil cylinder applies impact load to the top loading head through the impact force transmission rod; The transverse loading unit comprises left and right side loading oil cylinders, left and right loading heads, the left and right loading heads are arranged on the inner side of the confining pressure chamber through a transverse loading rod, the left and right side loading oil cylinders are symmetrically installed on the left and right sides of the main frame, and the left and right loading heads are synchronously applied with static load by the left and right side loading oil cylinders respectively; The longitudinal loading unit comprises front and rear side loading oil cylinders, front and rear loading heads, the front and rear loading heads are arranged on the inner side of the confining pressure chamber through a longitudinal loading rod, the front and rear side loading oil cylinders are symmetrically arranged on the front and rear sides of the main frame through a rotating arm, and the front and rear loading heads are synchronously applied with static load by the front and rear side loading oil cylinders respectively; A square groove is formed in the end face of the front loading head, a water channel is arranged in the longitudinal loading rod connected with the front loading head, and a water supply device supplies high-pressure water into the square groove through the water channel. 2.The stress-seepage coupling true triaxial creep disturbance loading test system according to claim 1, characterized in that, Two mechanical arms are symmetrically arranged on the lower part of the front and rear sides of the main frame, two hinge supports one are symmetrically arranged on the rear side wall of the main frame, and the left and right ends of the rear mechanical arm are detachably fixedly connected with the two hinge supports one respectively; Two hinge supports two are symmetrically arranged on the front side wall of the main frame, the left end of the front mechanical arm is hingedly connected with the left hinge support two, a pin shaft oil cylinder is arranged below the hinge support two, the pin shaft oil cylinder is fixedly connected with the right side of the main frame through an oil cylinder support one, and the pin shaft oil cylinder locks and fixes the right end of the front mechanical arm with the right hinge support two. 3.The stress-seepage coupling triaxial creep disturbance loading test system according to claim 1, characterized in that, The rear end of the in-out material platform is fixedly connected with the workbench, the upper surface of the in-out material platform is flush with the surface of the workbench, two linear grooves are symmetrically arranged on the upper surface of the workbench, the two linear grooves extend to the front end of the in-out material platform, and a positioning hole is formed in the middle part of the workbench. The linear transfer mechanism comprises a square base plate, a positioning column and four stroke oil cylinders, the four stroke oil cylinders are respectively installed on the upper surfaces of four corners of the square base plate, the bottom of the square base plate is provided with receiving grooves equal in number to the stroke oil cylinders and corresponding in position, one roller is embedded in each receiving groove, the rollers are fixedly installed on the piston rod ends of the corresponding stroke oil cylinders, and the rollers on the same side are matched with the linear grooves on the corresponding side; The positioning column is vertically fixed to the center of the bottom of the square base plate, and the lower end of the positioning column can penetrate into the positioning hole, so that the square base plate is fixedly connected with the workbench.

4. The stress-seepage coupling triaxial creep disturbance loading test system according to claim 1, characterized in that, The confining pressure chamber comprises a base, a barrel and a top cover, the base is fixed to the upper surface of the linear transfer mechanism, the base is in a circular table structure, the barrel is in a cylindrical structure with open ends and is vertically arranged above the base, the upper end of the barrel is fixedly and sealingly matched with the top cover, and the lower end of the barrel is sealingly matched with the base and is fixedly connected with the base through the clamping assembly; The lifting device comprises a lifting oil cylinder and a lifting rod, the cylinder body of the lifting oil cylinder is fixedly connected with the front side of the cross beam of the main frame through the oil cylinder support two, the lifting rod is vertically arranged, the upper end of the lifting rod is fixedly connected with the piston rod end of the lifting oil cylinder, the lower end of the lifting rod is fixedly provided with a connecting plate, the connecting plate is provided with a connecting bolt, and the connecting plate can be fixedly connected with the top cover through the connecting bolt.

5. The stress-seepage coupling triaxial creep disturbance loading test system according to claim 4, characterized in that, The upper surface of the base is provided with a circular boss, at least two sealing rings one are embedded on the side wall of the circular boss, all the sealing rings one are arranged at intervals along the axial direction of the base, the lower end of the barrel is externally sleeved on the circular boss and sealingly matched with the circumferential side wall of the circular boss; The outer side wall of the lower end of the barrel is provided with an annular protruding portion one, the upper portion of the outer side wall of the base is provided with an annular protruding portion two, the outer diameter of the annular protruding portion one is equal to the outer diameter of the annular protruding portion two; The clamping assembly comprises four clamping halves and a clamping hoop, the clamping halves are in a 1 / 4 circular arc shape with grooves on the inner sides, the four clamping halves are spliced into a circular ring and are clamped at the connection between the base and the lower end of the barrel, and the clamping hoop is externally sleeved on the four clamping halves to fixedly connect the lower end of the barrel with the base.

6. The stress-seepage coupling triaxial creep disturbance loading test system according to claim 1, characterized in that, The top loading oil cylinder, the left side loading oil cylinder, the right side loading oil cylinder, the front side loading oil cylinder and the rear side loading oil cylinder are each provided with an axial displacement sensor, the impact load oil cylinder is provided with an impact displacement sensor, each displacement sensor is in communication with the industrial computer, and the impact load oil cylinder and each loading oil cylinder are supplied with oil and return oil by the hydraulic station.

7. The stress-seepage coupling triaxial creep disturbance loading test system according to claim 2, characterized in that, The bottom center of the force collecting block is provided with a vertical external loading head, the piston rod end of the impact load oil cylinder is provided with an impact loading rod, the lower end of the impact loading rod is inserted and matched with the upper end of the impact force transmission rod through the vertical external loading head, and the upper end of the vertical loading rod is inserted and matched with the bottom of the vertical external loading head.

8. The stress-seepage coupling triaxial creep disturbance loading test system according to claim 7, characterized in that, The piston rod ends of the left side loading oil cylinder and the right side loading oil cylinder are each provided with a horizontal force transmission rod, the two horizontal force transmission rods are coaxially and oppositely arranged and are slidingly matched with the main frame along the axial direction of the main frame, and the corresponding ends of the two horizontal force transmission rods are each provided with a horizontal external loading head. The piston rod end of the front-side loading oil cylinder and the piston rod end of the rear-side loading oil cylinder are each provided with a longitudinal force transmission rod, the two longitudinal force transmission rods are coaxially and oppositely arranged, and are respectively in axial sliding fit with the corresponding mechanical arm, and the corresponding ends of the two longitudinal force transmission rods are also each provided with a longitudinal external loading head; All the external loading heads are provided with a force sensor, and all the force sensors are respectively in communication connection with the industrial computer.

9. The stress-seepage coupling triaxial creep disturbance loading test system according to claim 1, characterized in that, The two lateral loading rods are coaxially and oppositely arranged on the side wall of the confining pressure chamber, the two longitudinal loading rods are coaxially and oppositely arranged on the side wall of the confining pressure chamber, the lateral loading rods and the longitudinal loading rods are in axial sliding sealing fit with the side wall of the confining pressure chamber, and the axis of the lateral loading rod and the axis of the longitudinal loading rod are at the same height position; The side, away from each other, of the left loading head and the right loading head is respectively fixedly connected with the opposite end of the two lateral loading rods, and the side, away from each other, of the front loading head and the rear loading head is respectively fixedly connected with the opposite end of the two longitudinal loading rods, one end of each of the lateral loading rods and the longitudinal loading rods, located outside the confining pressure chamber, is respectively in plug-in fit with the corresponding external loading head; Each of the lateral loading rods and the longitudinal loading rods is provided with a reset spring, all the reset springs are located outside the confining pressure chamber, and the lateral loading rods and the longitudinal loading rods are each provided with an annular limiting portion for limiting the reset spring.

10. The stress-seepage coupling triaxial creep disturbance loading test system according to claim 9, characterized in that, The square groove is located on the rear end face of the front loading head, the outlet end of the water channel is located at the bottom of the square groove, the inlet end of the water channel is located on the circumferential surface of the longitudinal loading rod, and the water channel is connected with the water supply device through a high-pressure pipeline; The square groove in the rear end face of the front loading head is embedded with a water pressure sensor, a temperature sensor and an acoustic emission sensor, in addition, the front end face of the rear loading head and the adjacent end faces of the left loading head and the right loading head are each provided with the same acoustic emission sensor; The front side, the rear side, the left side and the right side of the circumferential outer wall of the confining pressure chamber are each provided with a group of signal interfaces, and each group of signal interfaces is electrically connected with the sensors in the corresponding loading head in the confining pressure chamber.

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