A dynamic impact shear device based on full shear-seepage coupling

Abstract

The present invention relates to the technical field of rock impact shear simulation, and specifically to a dynamic impact shear device based on full shear-seepage coupling, wherein a test cavity for placing rock simulation parts is provided inside a static loading frame, one side of the static loading frame is connected to a joint seepage module, and the side away from the joint seepage module is correspondingly connected to a seepage box; the static loading module includes four loading parts, an incident rod is parallel to one of the horizontally distributed loading parts, one end of the incident rod extends into the static loading frame and hits the outer wall of the first test block, and the other end is correspondingly connected to a cylinder to supply air to the incident rod through the cylinder, and the bullet impacts the first test block after the kinetic energy is increased by the incident rod. It has the functions of seepage and impact shear at the same time, is more suitable for complex geological environments, and reveals the dynamic shear characteristics under deep rock water conditions.

Description

Technical Field

[0001] The invention belongs to the technical field of rock impact shear simulation, and in particular relates to a dynamic impact shear device based on full shear-seepage coupling. Background Art

[0002] With the exhaustion of shallow resources, rock engineering has gradually developed into deep areas in recent years. However, the construction of underground rock engineering is often accompanied by high-velocity seepage caused by high osmotic pressure and high hydraulic gradient. At the same time, there are often a large number of cracks and joints in natural rock masses, which cause uncertainty in rock deformation and shear behavior. This kind of rock discontinuity itself is prone to dynamic loads, such as rock bursts, explosions, seismic loads and operational blasting. The existence of this kind of rock stability problem makes the stress-seepage coupling characteristics of deep rock joints a key scientific problem that urgently needs to be solved and applied to the stability analysis of large-scale deep underground engineering.

[0003] At present, the experimental research on the shear-seepage coupling characteristics of jointed rock samples has been developed in depth, but there are still many problems. Including the problem of not being able to stabilize the seepage water pressure difference well. Most of the existing test instruments directly use servo loading to control the seepage water pressure value at the water inlet, while there is no servo control at the water outlet. The water pressure difference between the two has a large deviation compared with the actual seepage water pressure; due to the sealing problem during the test, it is impossible to achieve high seepage water pressure, and it is impossible to conduct in-depth research on the shear-seepage coupling characteristics of joints under high seepage water pressure; the existing test system cannot perform large-scale flow measurement, and the accuracy is poor; there are few experimental results on the shear creep-seepage of rock joints. Therefore, the research on the changes in the mechanical deformation characteristics of rock joints under long-term seepage needs to be deepened.

[0004] Therefore, it is necessary to provide an improved technical solution to address the above-mentioned deficiencies in the prior art. Summary of the invention

[0005] The purpose of the present invention is to overcome the above-mentioned deficiencies in the prior art. The present invention provides a dynamic impact shearing device based on full shear-seepage coupling.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A dynamic impact shearing device based on full shear-seepage coupling, comprising:

[0008] A static loading frame, wherein a test cavity for placing a rock simulation member is provided inside the static loading frame, wherein the rock simulation member comprises a first test block and a second test block stacked in a longitudinal direction, wherein one side of the static loading frame is connected to a joint seepage module, and a side away from the joint seepage module is correspondingly connected to a seepage box;

[0009] A static loading module, wherein the static loading module comprises four loading members, wherein two of the loading members respectively perform static pressure loading on the first test block and the second test block, and the other two loading members perform static pressure loading on two opposite sides of the second test block;

[0010] as well as

[0011] A dynamic shear loading module, the dynamic shear loading module comprising:

[0012] An incident rod, wherein the incident rod is parallel to one of the horizontally distributed loading members, one end of the incident rod extends into the static loading frame and abuts against the outer wall of the first test block, and the other end is correspondingly connected to a cylinder;

[0013] A bullet is slidably mounted in the incident rod. In response to the air supply to the incident rod through the cylinder, the bullet impacts the first test block after the kinetic energy is increased by the incident rod.

[0014] Preferably, a hydraulic loading plate is provided between the loading member and the rock simulation member, and an adapter block corresponding to the second test block is provided on the hydraulic loading plate corresponding to the loading member in the horizontal direction.

[0015] Preferably, the incident rod passes through the static loading frame and the corresponding hydraulic loading plate and is fixedly connected to the hydraulic loading plate. A sealing head is slidingly and sealingly connected to the end of the incident rod, and the sealing head correspondingly contacts the outer wall of the first test block.

[0016] Preferably, the sealing head is a tubular structure coaxially distributed with the incident rod, one end of the sealing head corresponding to the first test block is a sealing end, and extends out of the static loading frame through a pressure-resistant tube.

[0017] Preferably, the joint seepage module comprises:

[0018] A water tank, wherein the water tank is connected to one side of the static loading frame through a water inlet pipe, and a water pressure sensor is provided on the water inlet pipe;

[0019] A seepage box, wherein a side of the static loading frame away from the water tank is connected to the seepage box through a water outlet pipe, and a first stop valve is provided on the water outlet pipe;

[0020] A back-pressure valve is connected between the first stop valve and the static loading frame, the back-pressure valve is correspondingly connected to a water pressure servo loader, a return pipe is connected between the back-pressure valve and the first stop valve via a second stop valve, and the return pipe is correspondingly connected to the water tank.

[0021] Preferably, a flow meter is provided between the second stop valve and the water tank, displacement sensors are provided on the first test block and the second test block, and the displacement sensor, the flow meter, the water pressure servo loader, and the water pressure sensor are correspondingly connected to the controller.

[0022] Preferably, the loading component is a hydraulic cylinder, a pressure sensor is provided between the hydraulic cylinder and the rock simulation component, and the hydraulic cylinder and the pressure sensor are correspondingly connected to the controller.

[0023] Preferably, a stress gauge is provided in the incident rod, and the stress gauge and the cylinder are correspondingly connected to the controller.

[0024] Beneficial effects: It has the functions of seepage and impact shear at the same time, which is more suitable for complex geological environment, reveals the dynamic shear characteristics of deep rock under water conditions, and helps to explore the dynamic shear failure mechanism under rock seepage conditions. It can clearly grasp the shear failure mechanism and influencing factors of different catastrophic events such as landslides, fault talc eruptions and earthquakes. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them:

[0026] Figure 1 This is a simplified structural diagram of the dynamic impact shearing device in a specific embodiment provided by the present invention.

[0027] In the figure: 1. water tank; 2. water pressure sensor; 3. sealing head; 4. static loading frame; 5. first test block; 6. second test block; 7. flow meter; 8. first stop valve; 9. back pressure valve; 10. second stop valve; 11. electronic scale; 12. loader; 13. water pressure servo loader; 14. adapter block; 15. hydraulic loading plate; 16. strain gauge; 17. incident rod; 18. cylinder; 19. bullet; 20. controller. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention belong to the scope of protection of the present invention.

[0029] In the description of the present invention, the terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention. The terms "connected" and "connected" used in the present invention should be understood in a broad sense. For example, they can be fixed connections or detachable connections; they can be directly connected or indirectly connected through intermediate components. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0030] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

[0031] The common shear-seepage coupling system at present can only study the shear-seepage coupling under static normal load, but cannot study the dynamic shear response of rock discontinuities under the combined action of static normal stress and impact load. Therefore, it cannot fit the complex geological environment of the rock mass in actual situations. Although the direct use of in-situ dynamic shear tests can more effectively evaluate the dynamic shear characteristics of rocks, the construction is difficult during field tests, which can easily destroy the water supply of the existing rock mass, and is costly and inefficient. Exploring the dynamic shear failure mechanism of rock under seepage conditions in the laboratory can clearly grasp the shear failure mechanism and influencing factors of different catastrophic events such as landslides, fault talc eruptions and earthquakes. Figure 1 As shown, a dynamic impact shear device based on full shear-seepage coupling includes a static loading frame 4, a static loading module and a dynamic shear loading module. The static loading frame 4 is a metal box structure. A test cavity for placing a rock simulation piece is provided inside the static loading frame 4. The test cavity is an independent closed cavity. A detachable end cover is provided on the static loading frame 4 for taking and placing the rock simulation piece. The rock simulation piece includes a first test block 5 and a second test block 6 stacked along the longitudinal direction. The rock simulation piece is a rectangular structure formed by milling the rock blocks. After being loaded into the test cavity, a displacement sensor is installed. The displacement sensor is used to monitor the longitudinal and horizontal displacements of the rock simulation piece.

[0032] One side of the static loading frame 4 is connected to the joint seepage module, and the side away from the joint seepage module is correspondingly connected to the seepage box. After checking the connection status of the inlet and outlet of the joint shear seepage box, the joint seepage module is turned on, and the water inlet pressure is adjusted to the preset pressure state. After it stabilizes, the pressure state of the water outlet pressure is continued to be adjusted so that the difference between the inlet and outlet water pressures reaches the value set in the test and remains stable. During the test, the rock is in a shear seepage coupling state under dynamic impact.

[0033] The static loading module includes four loading members 12, two of which perform static pressure loading on the first test block 5 and the second test block 6 respectively, thereby providing a static loading force in the longitudinal direction, and the other two loading members 12 perform static pressure loading on the opposite sides of the second test block 6, thereby forming a static loading force loaded in two orthogonal directions. For the static biaxial load on the specimen, the maximum load capacity of each hydraulic loading piston is up to 130 kN.

[0034] The dynamic shear loading module includes an incident rod 17 and a bullet 19, wherein the incident rod 17 is parallel to one of the horizontally distributed loading members 12 and is used to provide guidance for the bullet 19. After one end of the incident rod 17 extends into the static loading frame 4, it abuts against the outer wall of the first test block 5, and the other end is correspondingly connected to a cylinder 18. The bullet 19 is slidably assembled in the incident rod 17 to form a piston assembly. When gas is supplied, the incident rod 17 can be continuously accelerated to obtain kinetic energy. Specifically, during the test, gas is supplied to the incident rod 17 through the cylinder 18. After the kinetic energy of the bullet 19 is increased by the incident rod 17, it impacts the first test block 5. The impact kinetic energy of the bullet 19 can be adjusted by adjusting the internal pressure of the cylinder 18.

[0035] In an optional embodiment, a hydraulic loading plate 15 is provided between the loader 12 and the rock simulation member, so that the hydraulic loading plate 15 acts evenly on the upper surface of the first test block 5, the lower surface of the second test block 6 and the two opposite side surfaces of the second test block 6. In order to ensure that the second test block 6 is subjected to force balance, an adapter block 14 corresponding to the second test block 6 is provided on the hydraulic loading plate 15 corresponding to the loader 12 in the horizontal direction, and the shape of the adapter block 14 is adapted to the shape of the corresponding side surface of the second test block 6, so as to ensure stable force.

[0036] In an optional embodiment, the incident rod 17 is a hollow metal tube, which passes through the static loading frame 4 and the corresponding hydraulic loading plate 15, and is fixedly connected to the hydraulic loading plate 15 by nuts or welding. A sliding seal is provided between the incident rod 17 and the static loading frame 4, so that the position of the incident rod 17 can be adjusted according to the actual size of the rock simulation part. A sealing head 3 is slidingly sealed at the end of the incident rod 17, and the sealing head 3 corresponds to the outer wall of the first test block 5, so that the impact force of the bullet 19 can act on the test block.

[0037] In this embodiment, in order to ensure that the seepage liquid does not flow out with the incident rod 17, the sealing head 3 is designed to be a tubular structure distributed concentrically with the incident rod 17. The open end of the sealing head 3 can be slidably assembled inside the incident rod 17, and can be sleeved on the outside of the incident rod 17, and a sliding seal is performed through a sliding sealing ring. In actual use, the sealing head 3 is close to the side wall of the first test block 5, thereby avoiding pressure changes inside the static loading frame 4 during the impact process.

[0038] One end of the sealing head 3 corresponding to the first test block 5 is the sealing end, and extends out of the static loading frame 4 through a pressure-resistant tube. The pressure-resistant tube can be a corrugated tube so as not to affect the displacement of the sealing head 3 during the impact process. The sealing head 3 and the outside are connected through the pressure-resistant tube, thereby preventing the gas pressure from affecting the normal impact of the bullet 19.

[0039] In this embodiment, by measuring the sliding friction between the sealing head 3 and the incident rod 17, the impact kinetic energy is obtained by subtracting the energy for overcoming the friction from the kinetic energy of the bullet 19, thereby ensuring the accuracy of the test.

[0040] Preferably, the outer wall of the sealing head 3 is provided with a step with an increased outer diameter, and an extrusion spring is provided between the step and the hydraulic loading plate 15. The driving force of the extrusion spring is greater than the driving force of the pressure in the static loading frame 4 on the sealing head 3 under the test state, so that the sealing head 3 is driven to be close to the first test block 5, thereby overcoming the influence of the pressure in the static loading frame 4 on the test.

[0041] In an optional embodiment, the joint seepage module includes a water tank 1 and a seepage box. The water tank 1 is connected to one side of the static loading frame 4 through an inlet pipe, and a water pressure sensor 2 is provided on the inlet pipe; the side of the static loading frame 4 away from the water tank 1 is connected to the seepage box through an outlet pipe, thereby forming a seepage channel, and a first stop valve 8 is provided on the outlet pipe. The first stop valve 8 can be a pressure relief valve, so that the inside of the static loading frame 4 maintains a constant pressure and forms a seepage coupling state through the flow of seepage water. A back pressure valve 9 is provided between the first stop valve 8 and the static loading frame 4, and the back pressure valve 9 is connected to a water pressure servo loader 13, which can pressurize the inside of the pipeline. , thereby ensuring that the preset pressure seepage is maintained inside the static loading frame 4. A return pipe is connected between the back pressure valve 9 and the first stop valve 8 through the second stop valve 10, and the return pipe is connected to the water tank 1 accordingly. First, the first stop valve 8 is closed and the second stop valve 10 is opened, and the internal pressure is increased through the back pressure valve 9. Then the first stop valve 8 is opened and the second stop valve 10 is closed, so that the internal pressure can flow out slowly. The water tank 1 can be a closed tank body that can withstand high pressure. The water tank 1 is connected to the water pressure sensor 2 to ensure that the water pressure stably transports water to the shear seepage box, thereby meeting the high pressure requirements of the test. An electronic scale 11 is provided below the seepage box to weigh the seepage water.

[0042] In an optional embodiment, a flow meter 7 is provided between the second stop valve 10 and the water tank 1. An electronic scale 11 is used to record the initial stage of the test. When the seepage flow rate increases, the flow meter 7 is switched to record the seepage flow rate. If the seepage flow rate is small during the overall test stage, the electronic scale 11 can be used to record the weight of the seepage water. If the seepage flow rate is large, the flow meter 7 can be used to measure the seepage flow rate. The combination of the two methods ensures the accuracy of the test results. Displacement sensors are provided on the first test block 5 and the second test block 6. The displacement sensor, flow meter 7, water pressure servo loader 13, and water pressure sensor 2 are correspondingly connected to the controller 20.

[0043] The controller 20 is connected to a control panel, and during the test, a control signal is sent through the control panel to instruct each electronic component to respond, and to collect, display and save data for the entire test process. The controller 20 is installed with analysis software that can automatically analyze the saved data.

[0044] In an optional embodiment, the loading member 12 is a hydraulic cylinder, which can be arranged inside the static loading frame 4. A pressure sensor is provided between the hydraulic cylinder and the rock simulation member. The hydraulic cylinder and the pressure sensor are correspondingly connected to the controller 20, which can control the loading pressure.

[0045] A strain gauge 16 is provided in the incident rod 17. The strain gauge 16 and the cylinder 18 are correspondingly connected to a controller 20. The speed of the bullet 19 is sensed by the strain gauge 16, so that the kinetic energy is obtained by calculation.

[0046] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are within the scope of protection of the pending claims of the present invention.

Claims

1. A dynamic impact shearing device based on full shear-seepage coupling, characterized in that: include: A static loading frame, wherein a test cavity for placing a rock simulation member is provided inside the static loading frame, wherein the rock simulation member comprises a first test block and a second test block stacked in a longitudinal direction, wherein one side of the static loading frame is connected to a joint seepage module, and a side away from the joint seepage module is correspondingly connected to a seepage box; A static loading module, wherein the static loading module comprises four loading members, wherein two of the loading members respectively perform static pressure loading on the first test block and the second test block, and the other two loading members perform static pressure loading on two opposite sides of the second test block; as well as A dynamic shear loading module, the dynamic shear loading module comprising: An incident rod, wherein the incident rod is parallel to one of the horizontally distributed loading members, one end of the incident rod extends into the static loading frame and abuts against the outer wall of the first test block, and the other end is correspondingly connected to a cylinder; a bullet, the bullet being slidably mounted in the incident rod, and in response to the air being supplied to the incident rod through the cylinder, the bullet passes through the incident rod and increases its kinetic energy before impacting the first test block; The static loading frame is a metal box structure, and the test cavity is an independent closed cavity; The incident rod is a hollow metal tube, which passes through the static loading frame and the corresponding hydraulic loading plate, and is fixedly connected to the hydraulic loading plate by nuts or welding. A sliding seal is provided between the incident rod and the static loading frame, and a sealing head is connected to the end of the incident rod in a sliding seal, and the sealing head is correspondingly abutted against the outer wall of the first test block, so that the impact force of the bullet acts on the test block; The sealing head is a tubular structure that is concentrically distributed with the incident rod. The open end of the sealing head can be slidably assembled inside the incident rod, and the sealing head is close to the side wall of the first test block. The sealing head corresponds to one end of the first test block as a sealing end, and extends out of the static loading frame through a pressure-resistant tube to prevent the gas pressure from affecting the impact of the bullet; The outer wall of the sealing head is provided with a stepped platform with an increased outer diameter, and an extrusion spring is provided between the stepped platform and the hydraulic loading plate. The driving force of the extrusion spring is greater than the driving force of the pressure in the static loading frame on the sealing head under the test state, so that the driving sealing head is pressed against the first test block to overcome the influence of the pressure in the static loading frame on the test.

2. The dynamic impact shearing device based on full shear-seepage coupling according to claim 1 is characterized in that: A hydraulic loading plate is provided between the loading member and the rock simulation member, and an adapter block corresponding to the second test block is provided on the hydraulic loading plate corresponding to the loading member in the horizontal direction.

3. The dynamic impact shearing device based on full shear-seepage coupling according to claim 2 is characterized in that: The incident rod passes through the static loading frame and the corresponding hydraulic loading plate and is fixedly connected to the hydraulic loading plate. A sealing head is slidably and sealingly connected to the end of the incident rod, and the sealing head correspondingly contacts the outer wall of the first test block.

4. The dynamic impact shearing device based on full shear-seepage coupling according to claim 3 is characterized in that: The sealing head is a tubular structure coaxially distributed with the incident rod, and one end of the sealing head corresponding to the first test block is a sealing end, and extends out of the static loading frame through a pressure-resistant tube.

5. The dynamic impact shearing device based on full shear-seepage coupling according to claim 1, characterized in that: The joint seepage module comprises: A water tank, wherein the water tank is connected to one side of the static loading frame through a water inlet pipe, and a water pressure sensor is provided on the water inlet pipe; A seepage box, wherein a side of the static loading frame away from the water tank is connected to the seepage box through a water outlet pipe, and a first stop valve is provided on the water outlet pipe; A back-pressure valve is connected between the first stop valve and the static loading frame, the back-pressure valve is correspondingly connected to a water pressure servo loader, a return pipe is connected between the back-pressure valve and the first stop valve via a second stop valve, and the return pipe is correspondingly connected to the water tank.

6. The dynamic impact shearing device based on full shear-seepage coupling according to claim 5, characterized in that: A flow meter is provided between the second stop valve and the water tank, and displacement sensors are provided on the first test block and the second test block. The displacement sensor, the flow meter, the water pressure servo loader, and the water pressure sensor are correspondingly connected to the controller.

7. The dynamic impact shearing device based on full shear-seepage coupling according to claim 6, characterized in that: The loading component is a hydraulic cylinder, a pressure sensor is arranged between the hydraulic cylinder and the rock simulation component, and the hydraulic cylinder and the pressure sensor are correspondingly connected to the controller.

8. The dynamic impact shearing device based on full shear-seepage coupling according to claim 6, characterized in that: A stress gauge is arranged inside the incident rod, and the stress gauge and the cylinder are correspondingly connected to the controller.

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