True triaxial creep disturbance loading test system under stress-seepage coupling

Abstract

The invention discloses a true triaxial creep disturbance loading test system under stress-seepage coupling, which comprises a test host, a hydraulic station, a power distribution cabinet, a water supply device and an industrial personal computer, and is characterized in that the test host comprises a workbench, a confining pressure chamber, a vertical loading unit, a transverse loading unit, a longitudinal loading unit, a lifting device and a feeding and discharging platform, and the top of the workbench is provided with a host frame; the confining pressure chamber is located on the inner side of the main machine frame, and the vertical loading unit comprises an impact load oil cylinder, a top loading oil cylinder, a top loading head and an impact dowel bar. 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, and 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. Long-time loading is carried out in a multi-dimensional stress environment, the seepage effect and dynamic disturbance are introduced, the real stress and seepage states of the abandoned mine laneway under the pumped storage condition are simulated, and theoretical and experimental bases are provided for pumped storage application of the abandoned mine.

Description

Technical Field

[0001] The invention relates to the technical field of rock mechanics engineering, and in particular to a true triaxial creep disturbance loading test system under stress-seepage coupling. Background Art

[0002] With the development of the mining industry, a large number of mines have been abandoned after the resources have been mined. How to rationally develop and utilize these abandoned mines has become one of the important issues of resource recycling and environmental protection. In recent years, the use of abandoned mines for pumped storage has become an emerging green energy storage method. By transforming the mine space into energy storage facilities, it can not only make full use of waste resources, but also effectively alleviate the peak-valley load difference of the power system, providing a new solution for the storage and peak regulation of new energy. However, the application of pumped storage in abandoned mine tunnels involves complex geological conditions and engineering technical challenges, especially the long-term stability of rock mass under high water pressure and complex stress environments.

[0003] Traditional test equipment is difficult to simulate the multi-dimensional stress, seepage conditions and long-term creep effects in the tunnel at the same time, so it is difficult to truly reproduce the actual stress state of the mine tunnel during the pumped storage process. The existing triaxial test equipment is mainly suitable for loading in a single stress or single seepage environment, and lacks the means to study the long-term mechanical behavior of rocks under the coupling of multiple factors. Therefore, the existing technology urgently needs to be further improved. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, one object of the present invention is to propose a true triaxial creep perturbation loading test system under stress-seepage coupling, so as to solve the problem that the existing test equipment is difficult to simultaneously simulate the multi-dimensional stress, seepage conditions and long-term creep effects in the tunnel, and is difficult to truly reproduce the actual stress state of the rock mass in the mine tunnel during the pumping storage process.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

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

[0007] The feeding and discharging platform is fixedly arranged at the front side of the workbench, the lifting device is installed at the upper front side of the main frame, and the confining pressure chamber is arranged 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 force transmission rod. The impact load cylinder is vertically arranged at the top center of the main frame. There are multiple top loading cylinders. All top loading cylinders are regularly arranged around the impact load cylinder. The actuator ends of each top loading cylinder are fixedly connected by a force collecting block.

[0009] The top loading head is arranged at the upper inner part of the confining pressure chamber through a vertical loading rod, and an impact force transmission rod is arranged coaxially with the vertical loading rod. The force collecting block applies a static load to the top loading head through the vertical loading rod, and the impact load cylinder applies an impact load to the top loading head through the impact force 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 loading head and the right loading head are relatively arranged left and right inside the confining pressure chamber through a lateral loading rod. The left loading cylinder and the right loading cylinder are symmetrically installed on the left and right sides of the main frame, and static loads are synchronously applied to the left loading head and the right loading head 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 relatively arranged in the confining pressure chamber front and back through a longitudinal loading rod. The front loading cylinder and the rear loading cylinder are symmetrically arranged on the front and rear sides of the main frame through a rotating arm, and static loads are synchronously applied to the front loading head and the rear loading head respectively.

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

[0013] Furthermore, two mechanical arms are symmetrically arranged at the lower part of the front and rear sides of the main frame, and two hinge supports 1 are symmetrically arranged on the rear side wall of the main frame. The left and right ends of the rear mechanical arms are respectively detachably fixedly connected to the two hinge supports 1.

[0014] There are two left-right symmetrical hinge supports on the front side wall of the main frame. The left end of the front mechanical arm is hinged to the hinge support 2 on the left. A pin cylinder is provided under the hinge support 2. The pin cylinder is fixedly connected to the right side of the main frame through a cylinder bracket 1. The pin cylinder locks the right end of the front mechanical arm with the hinge support 2 on the right.

[0015] Furthermore, the rear end of the feed and discharge platform is fixedly connected to the workbench, and its upper surface is flush with the surface of the workbench. Two straight grooves are symmetrically arranged on the upper surface of the workbench, and the two straight grooves extend to the front end of the feed and discharge platform. A positioning hole is opened in the middle of the workbench.

[0016] The linear transfer mechanism includes a square base plate, a positioning column and four stroke cylinders. The four stroke cylinders are respectively installed on the upper surfaces of the four corners of the square base plate. The bottom of the square base plate is provided with storage grooves whose number is equal to the stroke cylinders and whose positions correspond to each other. A roller is embedded in each storage groove. Each of the rollers is fixedly installed on the piston rod end of the corresponding stroke cylinder above it, and the two rollers on the same side are matched with the linear grooves on the corresponding side.

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

[0018] Furthermore, the confining pressure chamber includes a base, a cylinder body and a top cover, wherein the base is fixed to the upper surface of the linear transfer mechanism, the base is a truncated cone-shaped structure, the cylinder body is a cylindrical structure with openings at both ends, and is vertically arranged above the base, the upper end of the cylinder body is fixedly sealed with the top cover, and the lower end of the cylinder body is sealed with the base and is 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 2. The lifting rod is arranged vertically. The upper end of the lifting rod is fixedly connected to the end of the piston rod of the lifting cylinder. A connecting plate is fixed to the lower end. The connecting plate is provided with connecting bolts, which 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 sealing rings are arranged at intervals along the axial direction of the base. The lower end of the cylinder body is sleeved on the outside of the circular boss and sealed with the circumferential side wall of the circular boss.

[0021] The outer wall of the lower end of the barrel is provided with an annular protrusion 1, and the upper part of the outer wall of the base is provided with an annular protrusion 2, and the outer diameter of the annular protrusion 1 is equal to the outer diameter of the annular protrusion 2.

[0022] The clamping assembly includes a clamping flap and a clamping hoop. There are four clamping flaps, each of which is in the shape of a 1 / 4 arc with a groove on the inner side. The four clamping flaps are spliced ​​into a circular ring, which is clamped at the connection between the base and the lower end of the cylinder body. The clamping hoop is sleeved on the outside of the four clamping flaps to fix the lower end of the cylinder body to the base.

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

[0024] Furthermore, a vertical external loading head is provided at the bottom center of the force collecting 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 plugged into and matched with the upper end of the impact force transmission rod, and the upper end of the vertical loading rod is plugged into and matched with the bottom of the vertical external loading head.

[0025] Furthermore, a transverse force transmission rod is provided at the end of the piston rod of the left loading cylinder and the right loading cylinder. The two transverse force transmission rods are coaxially arranged relative to each other and slideably cooperate with the main frame along its axial direction. A transverse external loading head is provided at the corresponding end of the two transverse force transmission rods.

[0026] The piston rod ends of the front loading cylinder and the rear loading cylinder are each provided with a longitudinal force transmission rod, the two longitudinal force transmission rods are coaxially arranged relative to each other, and respectively cooperate with the corresponding mechanical arms along their axial sliding, and the corresponding ends of the two longitudinal force transmission rods are also provided with a longitudinal external loading head.

[0027] All external loading heads are equipped with a force sensor, and all force sensors are respectively connected to the industrial control computer for communication.

[0028] Furthermore, the two transverse loading rods are coaxially arranged on the side wall of the confining pressure chamber, and the two longitudinal loading rods are coaxially arranged on the side wall of the confining pressure chamber. Both the transverse loading rod and the longitudinal loading rod are slidingly sealed with the side wall of the confining pressure chamber along their axial directions, and the axis of the transverse loading rod and the axis of the longitudinal loading rod are at the same height position.

[0029] The sides of the left loading head and the right loading head facing away from each other are fixedly connected to the opposite ends of the two transverse loading rods, and the sides of the front loading head and the rear loading head facing away from each other are fixedly connected to the opposite ends of the two longitudinal loading rods. Each transverse loading rod and the longitudinal loading rod are located at one end outside the confining pressure chamber and are respectively plugged into and matched with the corresponding external loading heads.

[0030] A reset spring is sleeved on each transverse loading rod and each longitudinal loading rod. All the reset springs are located outside the confining pressure chamber. The transverse loading rod and the longitudinal loading rod are provided with an annular limiting portion for limiting the reset spring.

[0031] Furthermore, the square groove is located on the rear end surface 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 where 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 of the rear end face of the front loading head. 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 all provided with the same acoustic emission sensor.

[0033] A group of signal interfaces are respectively arranged on the front side, the rear side, the left side and the right side of the circumferential outer wall of the confining pressure chamber, and each group of signal interfaces is electrically connected to the sensor in the loading head corresponding to the position in the confining pressure chamber.

[0034] By adopting the above technical scheme, the beneficial technical effect of the present invention is: the present invention controls the water pressure in the square groove on the front loading head, performs seepage operation on one side of the sample, controls the output pressure of the combined loading head on the sample, and controls the top loading head to load the sample with impact load, so as to achieve true triaxial loading test of rock samples under dynamic and static load seepage coupling conditions. Acoustic emission monitoring means are used to monitor the rock fracture damage data of the loaded sample in real time, water pressure monitoring means are used to monitor the water pressure data in the confining pressure chamber in real time, temperature monitoring sensors are used to monitor the rock temperature data of the sample in real time, and displacement sensors are used to monitor the deformation data of the sample in real time, so as to realize the damage evolution analysis in the process of rock fracture, and provide important parameters for breaking through the rock mechanics theory under dynamic load-static load-seepage coupling and guiding on-site tunnel construction. BRIEF DESCRIPTION OF THE DRAWINGS

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

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

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

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

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

[0040] Figure 6 It is a three-dimensional diagram of the combined structure of the confining pressure chamber and related parts of the present invention.

[0041] Figure 7 yes Figure 6 A front view of the combined structure is shown in FIG.

[0042] Figure 8 yes Figure 6 A top view of the combined structure is shown in FIG.

[0043] Fig. 9 yes Figure 6 A vertical cross-sectional view of the combined structure is shown in FIG. DETAILED DESCRIPTION

[0044] The following embodiments of the present invention are described in further detail in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present 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 computer 104. The test host includes a workbench 1, a main frame 2, a confining pressure chamber 3, a vertical loading unit, a lateral loading unit, a longitudinal loading unit, a lifting device and a feeding and discharging platform 11. The main 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 mechanical arms 23 are symmetrically arranged at the lower part of the front and rear sides of the main frame 2. Two hinge supports 1 21 are symmetrically arranged on the rear side wall of the main frame 2. The left and right ends of the rear mechanical arm 23 are detachably fixedly connected to the two hinge supports 1 21. Two hinge supports 22 are symmetrically arranged on the front side wall of the main frame 2. The left end of the front mechanical arm 23 is hinged to the hinge support 22 on the left. A pin cylinder 24 is arranged below the hinge support 22. The pin cylinder 24 is fixedly connected to the right side of the main frame 2 through a cylinder bracket 1 25. The pin cylinder 24 locks and fixes the right end of the front mechanical arm 23 to the hinge support 22 on the right.

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

[0048] The confining pressure chamber 3 is arranged on the workbench 1 through a liftable linear transfer mechanism. Specifically, the confining pressure chamber 3 includes a base 31, a barrel 32 and a top cover 33. The base 31 is fixed to the upper surface of the linear transfer mechanism. The base 31 is a truncated cone structure. The barrel 32 is a cylindrical structure with openings at both ends and is vertically arranged above the base 31. The upper end of the barrel 32 is fixedly and sealedly matched with the top cover 33, and the lower end of the barrel 32 is sealedly matched with the base 31 and is fixedly connected to the base 31 through a clamping assembly.

[0049] The upper surface of the base 31 has a circular boss 311, and two sealing rings 312 are fixedly embedded on 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 barrel 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 the uniaxial loading test under the action of dynamic and static load confining pressure.

[0050] The outer wall at the lower end of the barrel 32 has an annular protrusion 1 321, and the upper part of the outer wall of the base 31 has an annular protrusion 2 313. The outer diameter of the annular protrusion 1 321 is equal to the outer diameter of the annular protrusion 2 313. The clamping assembly includes a clamping petal 34 and a clamping hoop 35. The clamping petal 34 has four 1 / 4 arc shapes with grooves on the inner side. The four clamping petals 34 are spliced ​​into a circular ring, which is clamped at the connection between the base 31 and the lower end of the barrel 32. The clamping hoop 35 is sleeved on the outside of the four clamping petals 34. The clamping force of the clamping hoop 35 tightens the four clamping petals 34, and the lower end of the barrel 32 is fixedly connected 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 surfaces of the four corners of the square base plate 41. The bottom of the square base plate 41 is provided with storage grooves equal in number to the stroke cylinders 43 and corresponding in position. A roller is embedded in each storage groove. Each of the rollers is fixedly installed on the piston rod end of the corresponding stroke cylinder 43 above it, and the two rollers on the same side are matched with the linear groove 111 on the corresponding side.

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

[0053] The lifting device is installed on the front upper part 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 2 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 provided with connecting bolts, which can be fixedly connected with the top cover 33 by bolts. The barrel 32 and the top cover 33 are lifted upward and separated from the base 31, and the sample 9 is placed on the surface of the circular boss 311 of the base 31. After that, the lifting cylinder 44 is placed below the barrel 32 and the top cover 33, and the lower end of the barrel 32 is sleeved with the circular boss 311, and then the base 31 is fixedly connected with the lower end of the barrel 32 through four clips 34 and a clamp 35, so that the sample 9 is enclosed 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 force transmission rod 54. The impact load cylinder 51 is vertically fixedly installed at the center position of the top of the main frame 2. There are four top loading cylinders 52, and the four top loading cylinders 52 are vertically and regularly arranged around the impact load cylinder 51. The impact load cylinder 51 and the top loading cylinder 52 are both supplied with oil and returned with oil 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, and 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 computer 104 for communication, and each displacement sensor monitors the deformation data of the sample 9 in three axial directions in real time.

[0056] The actuator ends of the four top loading cylinders 52 are fixedly connected together through a force collecting block 55 located below the cross beam of the main frame 2. A vertical external loading head 57 is fixedly installed at the bottom center of the force collecting block 55. The piston rods of the four top loading cylinders 52 are synchronously extended and retracted, and the force collecting block 55 and the external loading head located at the bottom of the force collecting block 55 are driven to rise or fall.

[0057] The top loading head 53 is arranged at the upper inner side of the confining pressure chamber 3 through the vertical loading rod 56. The vertical loading rod 56 has an impact force transmission rod 54 coaxially arranged therein. The impact force transmission rod 54 is slidably matched with the vertical loading rod 56 outside it. The force collecting block 55 applies a static load to the top loading head 53 through the vertical loading rod 56. The impact load cylinder 51 applies an impact load to the top loading head 53 through the impact force transmission rod 54. Furthermore, the top loading head 53 applies a vertical static load to the specimen 9, and the impact force transmission rod 54 applies a vertical impact load to the specimen 9 through 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 thereto, the lower end of the impact loading rod 58 passes through the vertical external loading head 57 and is plugged into and matched with the upper end of the impact force transmission rod 54, the impact loading rod 58 is passed through the inner side of the vertical external loading head 57 and vertically slides with it, the upper end of the vertical loading rod 56 is plugged into and matched with the vertical external loading head 57 at the bottom of the force collecting block 55, the impact load cylinder 51 drives the impact loading rod 58 to rise and fall, applies impact force to the impact force transmission rod 54 and transmits 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 fixedly installed on the left and right sides of the main frame 2. The left loading cylinder 61 and the right loading cylinder 62 are respectively configured with the same axial displacement sensor 521. The left loading cylinder 61 and the right loading cylinder 62 are both supplied with oil and returned with oil by the hydraulic station 101.

[0060] The piston rod ends of the left loading cylinder 61 and the right loading cylinder 62 are each provided with a transverse force transmission rod, the two transverse force transmission rods are coaxially arranged opposite to each other, and slide with the main frame 2 along its axial direction, and the corresponding ends of the two transverse force transmission rods are each provided with a transverse external loading head 66, the 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 loading cylinder 61 and the right loading cylinder 62 respectively apply static loads to the left loading head and the right loading head synchronously through the two transverse external loading heads 66 located at the ends of the transverse force transmission rods.

[0061] The left loading head and the right loading head are both relatively arranged in the confining pressure chamber 3 through a transverse loading rod 67. Specifically, the two transverse loading rods 67 are coaxially arranged on the left and right walls of the confining pressure chamber 3, and each transverse loading rod 67 slides with the side wall of the confining pressure chamber 3 along its axial direction. The sides of the left loading head and the right loading head that are away from each other are fixedly connected to the opposite ends of the two transverse loading rods 67, respectively. The two transverse loading rods 67 are located at one end outside the confining pressure chamber 3, and are respectively plugged and matched with the two transverse external loading heads 66 at the end of the transverse force transmission rod. The left loading cylinder 61 and the right loading cylinder 62 respectively drive the two transverse external loading heads 66 to move synchronously relative to each other, and the left loading head and the right loading head are driven to move synchronously relative to each other through the transverse loading rod 67 to load the sample 9 horizontally.

[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 through the above-mentioned rotating arm. 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 with oil by the hydraulic station 101.

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

[0064] The front loading head 73 and the rear loading head 74 are both arranged front and back relative to each other inside the confining pressure chamber 3 through a longitudinal loading rod 77. Specifically, the two longitudinal loading rods 77 are coaxially arranged on the front side wall and the rear side wall of the confining pressure chamber 3. The longitudinal loading rod 77 slides forward and backward with the side wall of the confining pressure chamber 3 along its axial direction. The axis of the transverse loading rod 67 and the axis of the longitudinal loading rod 77 are at the same height position. The sides of the front loading head 73 and the rear loading head 74 that are away from each other are fixedly connected to the opposite ends of the two longitudinal loading rods 77 respectively. The two longitudinal loading rods 77 are located at one end outside the confining pressure chamber 3 and are respectively plugged and matched with the two longitudinal external loading heads 76 at the end of the longitudinal force transmission rod 75. The front loading cylinder 71 and the rear loading cylinder 72 respectively drive the two longitudinal external loading heads 76 to move synchronously relative to each other, and the front loading head 73 and the rear loading head 74 are driven to move synchronously through the longitudinal loading rod 77 to load the sample 9 longitudinally.

[0065] A return spring 81 is sleeved on the two transverse loading rods 67 and the two longitudinal loading rods 77. All the return springs 81 are located outside the confining pressure chamber 3. The transverse loading rod 67 and the longitudinal loading rod 77 are provided with an annular limit portion 82 for limiting the return spring 81. In the unloaded state, the return spring 81 drives the corresponding transverse loading rod 67 or longitudinal loading rod 77 to move outward, so that the left loading head, the right loading head, the front loading head 73 and the rear loading head 74 are separated from the sample 9. Before placing the sample 9 inside the confining pressure chamber 3, the left loading head, the right loading head, the front loading head 73 and the rear loading head 74 are in an outward expansion state, which is convenient for placing the sample 9 inside the confining pressure chamber 3. The sample 9 of the present invention adopts a square specimen or a cylindrical specimen. The square specimen is suitable for true triaxial test under the action of dynamic and static load seepage coupling, and the cylindrical specimen is suitable for uniaxial test under the action of dynamic and static load confining pressure.

[0066] A square groove 731 is provided on the end surface of the front loading head 73, and 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 surface 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 where it is located, and is connected to the water supply device 103 through a high-pressure pipeline. Under the three-dimensional stress loading state, the water supply device 103 supplies water to the square groove 731 through the water channel 78 and adjusts the pressure of 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 pressure inside the square groove 731 on the side wall of the sample 9 in real time. The temperature sensor monitors the temperature of the high-pressure water inside the square groove 731. In addition, the front end face of the rear loading head 74, the adjacent end faces of the left loading head and the right loading head are all provided with the same acoustic emission sensor. The acoustic emission sensor is electrically connected to the acoustic emission detector through a data line. 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 group of signal interfaces 36 are respectively provided on the front side, rear side, left side and right side of the circumferential outer wall of the confining pressure chamber 3. Each group of signal interfaces 36 is electrically connected to the sensor in the loading head corresponding to the position in the confining pressure chamber 3. The water pressure sensor, temperature sensor and acoustic emission sensor are respectively connected to the corresponding external equipment through the signal interface 36.

[0068] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two; the orientations or positional relationships indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the mechanism or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0069] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0070] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. A true triaxial creep disturbance loading test system under stress-seepage coupling, 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 machine includes a workbench, a main frame, a confining pressure chamber, a vertical loading unit, a lateral loading unit, a longitudinal loading unit, a lifting device and an inlet and outlet platform. The main frame is an N-shaped steel frame structure that runs through the front and back and is fixed above the workbench. The inlet and outlet platform is fixedly arranged at the front side of the workbench. The lifting device is installed at the upper front side of the main frame. The confining pressure chamber is arranged on the workbench through a linear transfer mechanism that can be raised and lowered. The vertical loading unit includes an impact load cylinder, a top loading cylinder, a top loading head and an impact force transmission rod. The impact load cylinder is vertically arranged at the top center of the main frame. There are multiple top loading cylinders. All top loading cylinders are regularly arranged around the impact load cylinder. The execution ends of the top loading cylinders are fixedly connected through force collecting blocks. The top loading head is arranged at the upper inner part of the confining pressure chamber through a vertical loading rod, and an impact force transmission rod is arranged coaxially with the vertical loading rod. The force collecting block applies a static load to the top loading head through the vertical loading rod, and the impact load cylinder applies an impact load to the top loading head through the impact force transmission rod. The lateral loading unit includes a left loading cylinder, a right loading cylinder, a left loading head and a right loading head. The left loading head and the right loading head are both relatively arranged in the confining pressure chamber through a lateral loading rod. The left loading cylinder and the right loading cylinder are symmetrically installed on the left and right sides of the main frame to synchronously apply static loads to the left loading head and the right loading head respectively. The longitudinal loading unit comprises 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 relatively arranged in the confining pressure chamber through a longitudinal loading rod. The front loading cylinder and the rear loading cylinder are both symmetrically arranged at the front and rear sides of the main frame through a rotating arm, and static loads are applied to the front loading head and the rear loading head synchronously respectively. A square groove is provided on the end surface of the front loading head, a water channel is provided inside the longitudinal loading rod connected to the front loading head, and a water supply device supplies high-pressure water into the square groove through the water channel.

2. The true triaxial creep perturbation loading test system under stress-seepage coupling according to claim 1 is characterized in that: Two mechanical arms are symmetrically arranged at the lower part of the front and rear sides of the main frame, and two hinge supports 1 are symmetrically arranged on the rear side wall of the main frame, and the left and right ends of the rear mechanical arms are respectively detachably fixedly connected to the two hinge supports 1; There are two left-right symmetrical hinge supports on the front side wall of the main frame. The left end of the front mechanical arm is hinged to the hinge support 2 on the left. A pin cylinder is provided under the hinge support 2. The pin cylinder is fixedly connected to the right side of the main frame through a cylinder bracket 1. The pin cylinder locks the right end of the front mechanical arm with the hinge support 2 on the right.

3. The true triaxial creep perturbation loading test system under stress-seepage coupling according to claim 1 is characterized in that: The rear end of the feeding and discharging platform is fixedly connected to the workbench, and its upper surface is flush with the surface of the workbench. Two linear grooves are symmetrically arranged on the upper surface of the workbench, and the two linear grooves extend to the front end of the feeding and discharging platform. A positioning hole is opened in the middle of the workbench; The linear transfer mechanism comprises a square bottom plate, a positioning column and four stroke cylinders, the four stroke cylinders are respectively mounted on the upper surface of the four corners of the square bottom plate, the bottom of the square bottom plate is provided with storage grooves equal in number to the stroke cylinders and corresponding in position, each storage groove is embedded with a roller, each of the rollers is fixedly mounted on the piston rod end of the corresponding stroke cylinder above it, and the two rollers on the same side are matched with the linear grooves on the corresponding side; The positioning column is vertically fixed at the center of the bottom of the square bottom plate, and the lower end of the positioning column can be inserted into the positioning hole to fix the square bottom plate and the workbench.

4. The true triaxial creep perturbation loading test system under stress-seepage coupling according to claim 1 is characterized in that: The confining pressure chamber includes a base, a cylinder body and a top cover. The base is fixed to the upper surface of the linear transfer mechanism. The base is a truncated cone structure. The cylinder body is a cylindrical structure with openings at both ends and is vertically arranged above the base. The upper end of the cylinder body is fixedly sealed with the top cover, and the lower end of the cylinder body is sealed with the base and is fixedly connected to the base through a clamping component. 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 2. The lifting rod is arranged vertically. The upper end of the lifting rod is fixedly connected to the end of the piston rod of the lifting cylinder. A connecting plate is fixed to the lower end. The connecting plate is provided with connecting bolts, which can be fixedly connected to the top cover bolts.

5. The true triaxial creep perturbation loading test system under stress-seepage coupling according to claim 4 is characterized in that: 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 barrel is sleeved on the outside of the circular boss and is sealed with the circumferential side wall of the circular boss. The outer wall of the lower end of the barrel is provided with an annular protrusion 1, and the upper part of the outer wall of the base is provided with an annular protrusion 2, and the outer diameter of the annular protrusion 1 is equal to the outer diameter of the annular protrusion 2; The clamping assembly includes a clamping flap and a clamping hoop. There are four clamping flaps, each of which is in the shape of a 1 / 4 arc with a groove on the inner side. The four clamping flaps are spliced ​​into a circular ring, which is clamped at the connection between the base and the lower end of the cylinder body. The clamping hoop is sleeved on the outside of the four clamping flaps to fix the lower end of the cylinder body to the base.

6. The true triaxial creep perturbation loading test system under stress-seepage coupling according to claim 1 is characterized in that: The top loading cylinder, the left loading cylinder, the right loading cylinder, the front loading cylinder and the rear loading cylinder are all 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 computer for communication. The impact load cylinder and each loading cylinder are supplied with oil and returned with oil by the hydraulic station.

7. A true triaxial creep perturbation loading test system under stress-seepage coupling according to claim 2, characterized in that: A vertical external loading head is provided at the bottom center of the force collecting 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 plugged into and matched with the upper end of the impact force transmission rod, and the upper end of the vertical loading rod is plugged into and matched with the bottom of the vertical external loading head.

8. A true triaxial creep perturbation loading test system under stress-seepage coupling according to claim 7, characterized in that: A transverse force transmission rod is provided at the end of the piston rod of the left loading cylinder and the right loading cylinder. The two transverse force transmission rods are coaxially arranged opposite to each other and slideably cooperate with the main frame along its axial direction. A transverse external loading head is provided at the corresponding end of the two transverse force transmission rods. A longitudinal force transmission rod is provided at the end of the piston rod of the front loading cylinder and the rear loading cylinder. The two longitudinal force transmission rods are coaxially arranged opposite to each other and respectively slide with the corresponding mechanical arms along their axial directions. A longitudinal external loading head is also provided at the corresponding ends of the two longitudinal force transmission rods. All external loading heads are equipped with a force sensor, and all force sensors are respectively connected to the industrial control computer for communication.

9. The true triaxial creep perturbation loading test system under stress-seepage coupling according to claim 1 is characterized in that: The two transverse loading rods are coaxially arranged on the side wall of the confining pressure chamber, and the two longitudinal loading rods are coaxially arranged on the side wall of the confining pressure chamber. The transverse loading rod and the longitudinal loading rod are both axially slidably sealed with the side wall of the confining pressure chamber, and the axis of the transverse loading rod and the axis of the longitudinal loading rod are at the same height position; The sides of the left loading head and the right loading head facing away from each other are fixedly connected to the opposite ends of the two transverse loading rods, and the sides of the front loading head and the rear loading head facing away from each other are fixedly connected to the opposite ends of the two longitudinal loading rods. Each transverse loading rod and the longitudinal loading rod are located at one end outside the confining pressure chamber and are respectively plugged and matched with the corresponding external loading heads. A reset spring is sleeved on each transverse loading rod and each longitudinal loading rod. All the reset springs are located outside the confining pressure chamber. The transverse loading rod and the longitudinal loading rod are provided with an annular limiting portion for limiting the reset spring.

10. A true triaxial creep perturbation loading test system under stress-seepage coupling according to claim 9, characterized in that: The square groove is located on the rear end surface 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 where it is located, and is connected to the water supply device through a high-pressure pipeline; A water pressure sensor, a temperature sensor and an acoustic emission sensor are embedded in the square groove of the rear end face of the front loading head. In addition, the front end face of the rear loading head, the adjacent end faces of the left loading head and the right loading head are all provided with the same acoustic emission sensor. A group of signal interfaces are respectively arranged on the front side, the rear side, the left side and the right side of the circumferential outer wall of the confining pressure chamber, and each group of signal interfaces is electrically connected to the sensor in the loading head corresponding to the position in the confining pressure chamber.

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