A seepage-erosion coupled separated Hopkinson bar testing system and method

Abstract

The invention discloses a seepage-erosion coupling separated Hopkinson bar test system and method, including a mounting platform; a rock and soil particle in-situ seepage erosion device is installed on the mounting platform, and the separated Hopkinson bar is connected to the in-situ seepage erosion device; the in-situ seepage erosion device includes: a left pressure-bearing sleeve with openings at both ends, a middle pressure-bearing sleeve, and a right pressure-bearing sleeve; a retractable left water-stopping rubber is installed between the left pressure-bearing sleeve and the middle pressure-bearing sleeve; a right water-stopping rubber is installed between the middle pressure-bearing sleeve and the right pressure-bearing sleeve; the left pressure-bearing sleeve is provided with a flange on the side close to the left water-stopping rubber, and the right pressure-bearing sleeve is provided with a flange on the side close to the right water-stopping rubber; the flange of the left pressure-bearing sleeve, the left water-stopping rubber, the right water-stopping rubber, and the flange of the right pressure-bearing sleeve are fitted and fixed by a spring pressing steel rod. The test system of the invention can complete the simulation of the seepage erosion process, and carry out impact mechanics tests while keeping the rock and soil sample in the in-situ state after erosion.

Description

Technical Field

[0001] The invention relates to a seepage-erosion coupled separated Hopkinson bar testing system, belonging to the technical field of rock and soil environment simulation body devices. Background Art

[0002] When a high dam is built on a thick overburden, erosion is a prominent manifestation that affects the stability of the thick overburden. The fine gravel inside the thick overburden continuously migrates and flows under the action of the seepage water flow, exacerbating the heterogeneity of the internal structure of the dam foundation and increasing the risk of uneven settlement of the dam foundation. At the same time, a series of compaction effects such as particle crushing, filling, and rearrangement of gravel and stone materials inside the thick overburden caused by dynamic loads will further cause the physical and mechanical properties of gravel and stone materials to be highly nonlinear. Especially under frequent dynamic loads, gravel and stone materials at the dam foundation are prone to cumulative damage and worsen uneven settlement of the dam foundation. Therefore, studying the dynamic characteristics mechanism of rock and soil granular materials under the action of seepage-erosion coupling has very important theoretical value and engineering significance.

[0003] The split Hopkinson bar is the most commonly used test equipment for studying the dynamic characteristics of materials under medium and high strain rates. Current research mainly focuses on the impact mechanical properties of rock specimens under a single form of different moisture content or different axial pressures, axial pressure-temperature control coupling, and axial pressure-confining pressure coupling. The actual occurrence environment of rock and soil particles in the seepage and erosion zone in the deep overburden has not been considered. This is mainly because the existing technology has not yet achieved the reproduction of the dynamic loading of rock and soil particle materials under the action of seepage-erosion coupling. A single numerical simulation method cannot reveal the seepage-erosion disaster mechanism of rock and soil particles in the seepage and erosion zone in the deep overburden under dynamic loads. Therefore, it is necessary to explore the study of the dynamic characteristics of rock and soil particles under the action of seepage-erosion coupling from the perspective of in-situ experiments.

[0004] The existing water-mechanical coupling separated Hopkinson bar only considers the test process of seepage water passing through the rock sample, and has not yet considered the migration and loss process of fine particles that may be caused by rock and soil particles encountering seepage. Summary of the invention

[0005] The technical problem to be solved by the present invention is as follows: in the process of testing the dynamic properties of rock and soil particles under the action of seepage-erosion coupling, the environmental simulation body device of the separated Hopkinson bar in the prior art cannot realize in-situ seepage-erosion coupling dynamic loading, and cannot simulate the actual existence environment of rock and soil particles acting in the seepage erosion zone in the deep covering layer.

[0006] In order to solve the above technical problems, the present invention provides a seepage-erosion coupled separated Hopkinson bar testing system, comprising:

[0007] Installation platform;

[0008] An in-situ seepage erosion device for rock and soil particles is installed on the installation platform;

[0009] The split Hopkinson bar is connected to the in-situ seepage erosion device to provide dynamic loading test conditions;

[0010] The in-situ seepage erosion device comprises:

[0011] A left pressure-bearing sleeve, a middle pressure-bearing sleeve and a right pressure-bearing sleeve with openings at both ends;

[0012] Install a retractable left water-stop rubber between the left pressure-bearing sleeve and the middle pressure-bearing sleeve;

[0013] Install the right water-stop rubber between the middle pressure sleeve and the right pressure sleeve;

[0014] The left pressure-bearing sleeve is provided with a flange on the side close to the left water-stop rubber, and the right pressure-bearing sleeve is provided with a flange on the side close to the right water-stop rubber; the flange of the left pressure-bearing sleeve, the left water-stop rubber, the right water-stop rubber and the flange of the right pressure-bearing sleeve are fitted and fixed by a spring-pressed steel rod.

[0015] The aforementioned seepage-erosion coupled separated Hopkinson bar test system has a plurality of sliding holes arranged along the circumferential direction at the corresponding positions of the flange of the left pressure sleeve, the left water-stop rubber, the right water-stop rubber, and the flange of the right pressure sleeve, and a spring-pressed steel rod is installed in the sliding hole.

[0016] In the aforementioned seepage-erosion coupled separated Hopkinson bar testing system, the sliding holes on the flanges of the left pressure-bearing sleeve and the right pressure-bearing sleeve include outer holes and inner holes arranged radially, and the outer holes and the inner holes are connected.

[0017] The aforementioned seepage-erosion coupled separated Hopkinson bar testing system, the spring pressed steel rod comprises a rod portion, the rod portion is a porous hollow steel rod, a spring assembly and an end are respectively connected to both sides of the rod portion, an active buckle is arranged at the end of the spring assembly close to one side of the rod portion, the active buckle can be extended into a certain opening of the rod portion when it is popped up, and when the active buckle is retracted, the active buckle enters the interior of the rod portion and moves under the action of the spring assembly.

[0018] In the aforementioned seepage-erosion coupled separated Hopkinson bar test system, the left water-stop rubber 6 and the right water-stop rubber both include four sector-shaped pieces, which gradually adhere to form a circle during the process of moving toward the axis.

[0019] The aforementioned seepage-erosion coupled separated Hopkinson bar test system has a left metal gasket disposed inside the left pressure sleeve and close to the left water stop rubber, and the left metal gasket is fixed to the left pressure sleeve by bolts;

[0020] A right metal gasket is arranged inside the right pressure-bearing sleeve, close to the right water-stop rubber, and the right metal gasket is fixed to the right pressure-bearing sleeve by bolts.

[0021] The aforementioned seepage-erosion coupled separated Hopkinson bar test system, the separated Hopkinson bar adopts a one-dimensional Hopkinson bar, including an incident rod and a transmission rod, the incident rod and the transmission rod are respectively inserted into the outside of the left pressure-bearing sleeve and the outside of the right pressure-bearing sleeve, the incident rod is fitted with the left metal gasket, and the transmission rod is fitted with the right metal gasket.

[0022] A method for testing in-situ seepage erosion of rock and soil particles, comprising the following steps:

[0023] Step 1: When preparing the sample, replace some of the fine particles that are expected to be eroded with soluble inorganic salts of the same particle size, mix the rock and soil particles with the inorganic salts, and prepare a sample with the same initial physical properties as the sample of the original mixture of coarse and fine rock and soil particles;

[0024] Step 2: Connect the left pressure sleeve, the middle pressure sleeve, the right pressure sleeve, the left water-stop rubber and the right water-stop rubber by passing the spring-pressed steel rod through the outer hole of the sliding hole; fix the left metal gasket to the left pressure sleeve with bolts, fill the test sample rock and soil particles, and then fix the right metal gasket to the right pressure sleeve with bolts;

[0025] The incident rod is passed through the circular channel inside the left pressure-bearing sleeve to fit with the left metal gasket, and the transmission rod is passed through the circular channel inside the right pressure-bearing sleeve to fit with the right metal gasket;

[0026] Slide the spring-pressed steel rod from the outer hole to the inner hole of the sliding hole. During this process, the pressure sleeve devices do not move. The left water-stop rubber and the right water-stop rubber move radially with the spring-pressed steel rod until they are tightly fitted with the left metal gasket and the right metal gasket, so that the left water-stop rubber and the right water-stop rubber slide radially with the spring-pressed steel rod and tightly fit the surfaces of the left metal gasket and the right metal gasket. By pressing the spring component inside the spring-pressed steel rod, the length of the rod is reduced and the end is controlled to be stuck into the inner hole of the sliding hole, thereby fixing the left pressure sleeve, the right pressure sleeve, the left water-stop rubber, the right water-stop rubber and the left metal gasket and the right metal gasket;

[0027] Step 3: Use a water permeable filter fixing device to connect and fix the pressure sleeve to the water inlet channel and the water outlet channel, wherein the water permeable filter fixing bolts fix the water permeable filter, and the water inlet and outlet channel fixing bolts fix the water inlet channel and the water outlet channel, and use a CNC air pressure pump to introduce water in the upstream water tank into the in-situ seepage erosion device through the water inlet channel;

[0028] Step 4: During the process of seepage water being injected into the rock and soil particles of the test sample, the soluble inorganic salts dissolve and flow out through the outlet channel along the direction of seepage and enter the downstream water-sand collection box. After the inorganic salts dissolve, the internal structure of the rock and soil particles of the test sample changes, thus completing the simulation process of in-situ seepage erosion;

[0029] Step 5: After the seepage erosion process is completed, close the water inlet valve, press the spring assembly in the spring-pressed steel rod to pop the end of the press-type steel rod open, slide the spring-pressed steel rod from the inner hole of the sliding hole to the outer hole, and press the spring assembly again to insert the end of the press-type steel rod into the outer hole, driving the left water-stop rubber and the right water-stop rubber to peel off the left metal gasket and the right metal gasket, so that the left metal gasket and the right metal gasket can slide without resistance in the middle pressure sleeve, and then carry out a dynamic impact test to determine the dynamic parameters of rock and soil particles eroded by seepage.

[0030] In the aforementioned in-situ seepage erosion test method for rock and soil particles, the kinetic parameters include:

[0031] Strength parameters: stress, strain, strain rate;

[0032] Seepage parameters: erosion rate, flow velocity.

[0033] The beneficial effects achieved by the present invention are as follows: the present invention is modified on the basis of an existing separated Hopkinson bar test system device to add a seepage erosion device, wherein the separated Hopkinson bar test system device includes an incident rod and a transmission rod. A seepage erosion device capable of filling rock and soil granular materials is added between the incident rod and the transmission rod, comprising a three-section pressure sleeve, a water-stopping rubber, a spring-pressed steel rod, a metal gasket, a water inlet and outlet channel, an upstream water tank with a numerically controlled air pressure pump, and a downstream water and sand collection device. During the seepage erosion process, the seepage erosion device performs a water-stopping seal by sliding the spring-pressed steel rod and moving it together with the water-stopping rubber so that it fits tightly with the pressure sleeve, thereby ensuring that the experimental effect will not be affected.

[0034] The present invention takes into account the phenomenon of fine particle loss during seepage erosion, and installs a seepage erosion device on the separated Hopkinson bar device. This test system adopts a specific method of simulating fine particle loss, and selects soluble inorganic salts with a particle size similar to that of fine particles to replace the fine particles that can be lost. Under the action of seepage water, the salt particles dissolve and are carried out of the sample with the water flow, ensuring that the internal structure of the sample changes after in-situ seepage erosion, completing the simulation of the seepage erosion process, and further carrying out impact mechanics tests while keeping the rock and soil sample in the in-situ state after erosion. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a front view of the rock and soil particle seepage-erosion coupling separated Hopkinson bar testing system device of the present invention;

[0036] Figure 2 It is a schematic diagram of the structure of the seepage erosion combined device of the present invention;

[0037] Figure 3a It is a schematic diagram of the structure of the spring pressing steel rod of the present invention when it is extended;

[0038] Figure 3b It is a schematic diagram of the structure of the spring-pressed steel rod of the present invention when it is contracted;

[0039] Figure 4 It is a schematic diagram of the sliding hole structure of the present invention;

[0040] Figure 5 It is a schematic structural diagram of the water permeable filter fixing device of the present invention.

[0041] Figure markings: 1. left metal gasket, 2. right metal gasket, 3. left pressure-bearing sleeve, 4. middle pressure-bearing sleeve, 5. right pressure-bearing sleeve, 6. left water-stop rubber, 7. right water-stop rubber, 8. spring-pressed steel rod, 9. incident rod, 10. transmission rod, 11. water inlet channel, 12. water outlet channel, 13. test sample rock and soil particles, 14. upstream water tank, 15. CNC air pressure pump, 16. water-sand collecting box, 1701. outer hole, 1702. inner hole, 801. spring assembly, 802. end, 803. rod, 804. movable buckle, 805. opening, 18. water inlet valve, 19. bolt, 20. water-permeable filter fixing device, 2001. water-permeable filter, 2002. water-permeable filter fixing bolt, 2003. water inlet and outlet channel fixing bolt. DETAILED DESCRIPTION

[0042] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0043] Example 1

[0044] This embodiment provides a seepage-erosion coupled separated Hopkinson bar testing system, comprising:

[0045] Installation platform;

[0046] An in-situ seepage erosion device for rock and soil particles is installed on the installation platform;

[0047] The split Hopkinson bar is connected to the in-situ seepage erosion device to provide dynamic loading test conditions.

[0048] like Figure 1 The in-situ seepage erosion device comprises:

[0049] A left pressure-bearing sleeve 3, a middle pressure-bearing sleeve 4 and a right pressure-bearing sleeve 5 with openings at both ends;

[0050] A retractable left water-stop rubber 6 is installed between the left pressure-bearing sleeve 3 and the middle pressure-bearing sleeve 4;

[0051] Install the right water-stop rubber 7 between the middle pressure-bearing sleeve 4 and the right pressure-bearing sleeve 5;

[0052] The left pressure-bearing sleeve 3 is provided with a flange on the side close to the left water-stop rubber 6, and the right pressure-bearing sleeve 5 is provided with a flange on the side close to the right water-stop rubber 7; the flange of the left pressure-bearing sleeve 3, the left water-stop rubber 6, the right water-stop rubber 7, and the flange of the right pressure-bearing sleeve 5 are fitted and fixed by a spring-pressed steel rod 8.

[0053] A plurality of sliding holes are provided along the circumferential direction at corresponding positions of the flange of the left pressure-bearing sleeve 3, the left water-stop rubber 6, the right water-stop rubber 7, and the flange of the right pressure-bearing sleeve 5. In this embodiment, there are four sliding holes, and a spring-pressed steel rod 8 is installed in the sliding hole.

[0054] The sliding holes on the flange of the left pressure-bearing sleeve 3 and the flange of the right pressure-bearing sleeve 5 include an outer hole 1701 and an inner hole 1702 arranged in the radial direction, and the outer hole 1701 and the inner hole 1702 are connected.

[0055] like Figure 3a and Figure 3b As shown, the spring pressing steel rod 8 includes a rod portion 803, and the rod portion 803 is a porous hollow steel rod. A spring component 801 and an end 802 are respectively connected to both sides of the rod portion 803. An active buckle 804 is provided at the end of the spring component 801 close to the rod portion 803. When the active buckle 804 pops up, it can extend into an opening of the rod portion 803. When the active buckle 804 retracts, the active buckle 804 enters the interior of the rod portion 803 and moves under the action of the spring component 801.

[0056] The two ends of the rod 803 are against the spring assembly 801, and there are multiple openings 805 on the rod 803. When the active buckle 804 is pressed, it can be pressed into the rod 803. At this time, the rod 803 can compress the spring assembly 801 to shorten the length of the entire steel rod 8, and when the rod 803 is compressed to the point where the opening 805 coincides with the active buckle 804, the active buckle automatically pops up to fix it again. If you need to restore the length of the entire steel rod 8, just repeat the same operation steps.

[0057] like Figure 2 As shown, the left water-stop rubber 6 and the right water-stop rubber 7 each include four sector-shaped pieces, which gradually adhere to form a circle during the process of moving toward the axis.

[0058] A left metal gasket 1 is arranged inside the left pressure-bearing sleeve 3 and near the left water-stop rubber 6, and the left metal gasket 1 is fixed to the left pressure-bearing sleeve 3 by bolts 19;

[0059] A metal gasket 2 is arranged inside the right pressure-bearing sleeve 5 and close to the right water-stop rubber 7 , and the right metal gasket 2 is fixed to the right pressure-bearing sleeve 5 by bolts 19 .

[0060] The separated Hopkinson rod adopts a one-dimensional Hopkinson rod, including an incident rod 9 and a transmission rod 10, which are respectively inserted into the outside of the left pressure-bearing sleeve 3 and the right pressure-bearing sleeve 5, the incident rod 9 is fitted with the left metal gasket 1, and the transmission rod 10 is fitted with the right metal gasket.

[0061] The spring-pressed steel rod 8 is fixed to the left water-stop rubber 6 and the right water-stop rubber 7 through the rod part 803. The ends 802 of the four spring-pressed steel rods 8 are first passed through the outer hole 1701 of the sliding hole, and then the rod part 803 of the spring-pressed steel rod 8 is moved so that the spring-pressed steel rod 8 moves along with the left water-stop rubber 6 and the right water-stop rubber 7 in the axial direction. When the spring-pressed steel rod 8 moves to the position of the inner hole 1702, the steel rod spring assembly 801 in the spring-pressed steel rod 8 is pressed and fixed with the movable buckle 804. The rod part 803 is shortened as a whole, and the end 802 is just stuck into the inner hole 1702 of the sliding hole, so that the spring-pressed steel rod 8 and the left water-stop rubber 6, the right water-stop rubber 7 are fitted and fixed with the left pressure-bearing sleeve 3, the middle pressure-bearing sleeve 4, and the right pressure-bearing sleeve 5. At the same time, the left water-stop rubber 6 and the right water-stop rubber 7 that were originally peeled off the metal gasket gradually fit the left metal gasket 1 and the right metal gasket 2 during the radial movement of the spring-pressed steel rod 8 to achieve good sealing for water stopping.

[0062] In this embodiment, a method for testing in-situ seepage erosion of rock and soil particles is provided, comprising the following steps:

[0063] Step 1: When preparing the sample, replace some of the fine particles that are expected to be eroded with soluble inorganic salts of the same particle size, mix the rock and soil particles with the inorganic salts, and prepare a sample with the same initial physical properties as the sample of the original mixture of coarse and fine rock and soil particles;

[0064] Step 2: If Figure 1-Figure 5 As shown in the figure, the separated Hopkinson bar is assembled with the rock and soil particle in-situ seepage erosion device:

[0065] First, the left pressure sleeve 3, the middle pressure sleeve 4, the right pressure sleeve 5, the left water-stop rubber 6 and the right water-stop rubber 7 are connected by passing the spring-pressed steel rod 8 through the outer hole of the sliding hole 17, and the left metal gasket 1 is first fixed to the left pressure sleeve 3 with bolts 19, and the test sample rock and soil particles 13 are filled, and then the right metal gasket 2 is fixed to the right pressure sleeve 5 with bolts 19;

[0066] The incident rod 9 passes through the circular channel inside the left pressure-bearing sleeve and fits with the left metal gasket 1, and the transmission rod 10 passes through the circular channel inside the right pressure-bearing sleeve and fits with the right metal gasket 2;

[0067] First, slide the spring pressing steel rod 8 from the outer hole 1701 of the sliding hole 17 to the inner hole 1702. During this process, the pressure sleeve devices do not move. The left water-stop rubber 6 and the right water-stop rubber 7 move radially with the spring pressing steel rod 8 until they are tightly fitted with the left metal gasket 1 and the right metal gasket 2, so that the left water-stop rubber 6 and the right water-stop rubber 7 slide radially with the spring pressing steel rod 8 and tightly fit the surfaces of the left metal gasket 1 and the right metal gasket 2, thereby playing a role in water stopping. By pressing the spring component 801 inside the spring pressing steel rod 8, the length of the rod part 803 is reduced and the end 802 is controlled to be stuck into the inner hole 1702 of the sliding hole 17, so that the left pressure sleeve 3, the right pressure sleeve 5, the left water-stop rubber 6, the right water-stop rubber 7 and the left metal gasket 1 and the right metal gasket 2 are fixed;

[0068] Step 3: If Figure 5 As shown, the middle pressure sleeve 4 is connected and fixed to the water inlet channel 11 and the water outlet channel 12 by using a water permeable filter fixing device 20, wherein the water permeable filter fixing bolt fixes the water permeable filter 2001, and the water inlet and outlet channel fixing bolts 2003 fix the water inlet channel 11 and the water outlet channel 12, and a numerically controlled air pressure pump 15 is used to introduce water in the upstream water tank 14 into the in-situ seepage erosion device through the water inlet channel 11;

[0069] Step 4: The seepage erosion simulation method is as follows: during the process of seepage water being injected into the test sample rock and soil particles 13, the soluble inorganic salts dissolve and flow out through the water outlet channel 12 along the direction of the seepage and enter the downstream water-sand collection box 16. After the inorganic salts dissolve, the internal structure of the test sample rock and soil particles changes, thus completing the simulation process of in-situ seepage erosion;

[0070] Step 5: After the seepage erosion process is completed, close the water inlet valve 18, press the spring assembly 801 in the spring press-type steel rod to bounce the press-type steel rod end 802 open, and slide the spring press-type steel rod 8 from the inner hole 1702 of the sliding hole 17 to the outer hole 1701, and press the spring assembly 801 again to insert the press-type steel rod end 802 into the outer hole 1701, driving the left water-stop rubber 6 and the right water-stop rubber 7 to peel off the left metal gasket 1 and the right metal gasket 2, so that the left metal gasket 1 and the right metal gasket 2 can slide without resistance in the middle pressure sleeve 4, and then carry out a dynamic impact test to determine the dynamic parameters of seepage erosion of rock and soil particles, the dynamic parameters include strength parameters stress, strain, strain rate, seepage parameters erosion rate, flow rate.

[0071] Example 2

[0072] A seepage-erosion coupled separated Hopkinson bar testing system, comprising:

[0073] Installation platform;

[0074] An in-situ seepage erosion device for rock and soil particles is installed on the installation platform;

[0075] The split Hopkinson bar is connected to the in-situ seepage erosion device to provide dynamic loading test conditions.

[0076] like Figure 1 The in-situ seepage erosion device comprises:

[0077] A left pressure-bearing sleeve 3, a middle pressure-bearing sleeve 4 and a right pressure-bearing sleeve 5 with openings at both ends;

[0078] A retractable left water-stop rubber 6 is installed between the left pressure-bearing sleeve 3 and the middle pressure-bearing sleeve 4;

[0079] Install the right water-stop rubber 7 between the middle pressure-bearing sleeve 4 and the right pressure-bearing sleeve 5;

[0080] The left pressure-bearing sleeve 3 is provided with a flange on the side close to the left water-stop rubber 6, and the right pressure-bearing sleeve 5 is provided with a flange on the side close to the right water-stop rubber 7; the flange of the left pressure-bearing sleeve 3, the left water-stop rubber 6, the right water-stop rubber 7, and the flange of the right pressure-bearing sleeve 5 are fitted and fixed by a spring-pressed steel rod 8.

[0081] The spring-pressed steel rods 8 are arranged in six numbers, and the sliding holes of the left pressure-bearing sleeve 3, the middle pressure-bearing sleeve 4, the right pressure-bearing sleeve 5, the left water-stop rubber 6 and the right water-stop rubber 7 are six; the left water-stop rubber 6 and the right water-stop rubber 7 are both composed of six fan-shaped pieces to form a circle.

[0082] Other technical features are the same as those of Example 1.

[0083] The above is a detailed description of the implementation mode of the present invention in conjunction with the accompanying drawings, but the above is only a preferred implementation mode of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A seepage-erosion coupled separated Hopkinson bar test system, characterized in that: include: Installation platform; An in-situ seepage erosion device for rock and soil particles is installed on the installation platform; The split Hopkinson bar is connected to the in-situ seepage erosion device to provide dynamic loading test conditions; The in-situ seepage erosion device comprises: A left pressure-bearing sleeve (3), a middle pressure-bearing sleeve (4), and a right pressure-bearing sleeve (5) having openings at both ends; A retractable left water-stop rubber (6) is installed between the left pressure-bearing sleeve (3) and the middle pressure-bearing sleeve (4); A right water-stop rubber (7) is installed between the middle pressure-bearing sleeve (4) and the right pressure-bearing sleeve (5); The left pressure-bearing sleeve (3) is provided with a flange on the side close to the left water-stop rubber (6), and the right pressure-bearing sleeve (5) is provided with a flange on the side close to the right water-stop rubber (7); the flange of the left pressure-bearing sleeve (3), the left water-stop rubber (6), the right water-stop rubber (7), and the flange of the right pressure-bearing sleeve (5) are fitted and fixed by a spring-pressed steel rod (8); A plurality of sliding holes are provided along the circumferential direction at corresponding positions of the flange of the left pressure-bearing sleeve (3), the left water-stop rubber (6), the right water-stop rubber (7), and the flange of the right pressure-bearing sleeve (5), and a spring-pressing steel rod (8) is installed in the sliding hole; A left metal gasket (1) is arranged inside the left pressure-bearing sleeve (3) and near the left water-stop rubber (6), and the left metal gasket (1) is fixed to the left pressure-bearing sleeve (3) by bolts (19); A right metal gasket (2) is arranged inside the right pressure-bearing sleeve (5) and near the right water-stop rubber (7), and the right metal gasket (2) and the right pressure-bearing sleeve (5) are fixed by bolts (19); The split Hopkinson rod adopts a one-dimensional Hopkinson rod, comprising an incident rod (9) and a transmission rod (10). The incident rod (9) and the transmission rod (10) are respectively inserted into the interior of the outer sides of the left pressure-bearing sleeve (3) and the right pressure-bearing sleeve (5). The incident rod (9) is fitted with the left metal gasket (1), and the transmission rod (10) is fitted with the right metal gasket.

2. A seepage-erosion coupled separated Hopkinson bar test system according to claim 1, characterized in that: The sliding holes on the flange of the left pressure-bearing sleeve (3) and the flange of the right pressure-bearing sleeve (5) comprise an outer hole (1701) and an inner hole (1702) arranged in a radial direction, and the outer hole (1701) and the inner hole (1702) are connected.

3. A seepage-erosion coupled separated Hopkinson bar testing system according to claim 2, characterized in that: The spring-pressed steel rod (8) comprises a rod portion (803), wherein the rod portion (803) is a porous hollow steel rod, and a spring assembly (801) and an end (802) are respectively connected to both sides of the rod portion (803), and an active buckle (804) is provided at an end of the spring assembly (801) close to the rod portion (803). When the active buckle (804) is ejected, it can extend into an opening of the rod portion (803), and when the active buckle (804) is retracted, the active buckle (804) enters the interior of the rod portion (803) and moves under the action of the spring assembly (801).

4. The seepage-erosion coupled separated Hopkinson bar test system according to claim 1, characterized in that: The left water-stop rubber (6) and the right water-stop rubber (7) each comprise four sector-shaped pieces, which gradually adhere to form a circle in the process of moving towards the axis.

5. The seepage-erosion coupled separated Hopkinson bar test system according to claim 1, characterized in that: The number of the spring-pressing steel rods (8) is 6, and the number of sliding holes of the left pressure-bearing sleeve (3), the middle pressure-bearing sleeve (4), the right pressure-bearing sleeve (5), the left water-stopping rubber (6) and the right water-stopping rubber (7) is 6; the left water-stopping rubber (6) and the right water-stopping rubber (7) are both composed of 6 fan-shaped pieces forming a circle.

6. A method for testing in-situ seepage erosion of rock and soil particles, characterized in that: The following steps are involved: Step 1: When preparing the sample, replace some of the fine particles that are expected to be eroded with soluble inorganic salts of the same particle size, mix the rock and soil particles with the inorganic salts, and prepare a sample with the same initial physical properties as the sample of the original mixture of coarse and fine rock and soil particles; Step 2: Connect the left pressure sleeve (3), the middle pressure sleeve (4), the right pressure sleeve (5), the left water-stop rubber (6) and the right water-stop rubber (7) by passing the spring-pressed steel rod (8) through the outer hole of the sliding hole (17); fix the left metal gasket (1) to the left pressure sleeve (3) with bolts (19), fill the test sample rock and soil particles (13), and then fix the right metal gasket (2) to the right pressure sleeve (5) with bolts (19); The incident rod (9) is passed through the circular channel inside the left pressure-bearing sleeve and is fitted with the left metal gasket (1), and the transmission rod (10) is passed through the circular channel inside the right pressure-bearing sleeve and is fitted with the right metal gasket (2); The spring pressing steel rod (8) is slid from the outer hole (1701) of the sliding hole (17) to the inner hole (1702). During this process, the pressure sleeve devices do not move. The left water-stop rubber (6) and the right water-stop rubber (7) move radially with the spring pressing steel rod (8) until they are tightly fitted with the left metal gasket (1) and the right metal gasket (2). The left water-stop rubber (6) and the right water-stop rubber (7) slide radially with the spring pressing steel rod (8) and tightly fit the surfaces of the left metal gasket (1) and the right metal gasket (2). The spring assembly (801) inside the spring pressing steel rod (8) is pressed to reduce the length of the rod (803) and control the end (802) to be stuck into the inner hole (1702) of the sliding hole (17), thereby fixing the left pressure sleeve (3), the right pressure sleeve (5), the left water-stop rubber (6), the right water-stop rubber (7) and the left metal gasket (1) and the right metal gasket (2); Step 3: Using a water permeable filter disc fixing device (20) to connect and fix the pressure sleeve (4) with the water inlet channel (11) and the water outlet channel (12), using a water permeable filter disc fixing bolt to fix the water permeable filter disc (2001), using inlet and outlet channel fixing bolts (2003) to fix the water inlet channel (11) and the water outlet channel (12), using a numerically controlled air pressure pump (15) to introduce water in the upstream water tank (14) into the in-situ seepage erosion device through the water inlet channel (11); Step 4: During the process of seepage water being injected into the test sample rock and soil particles (13), the soluble inorganic salts are dissolved and flow out through the outlet channel (12) along the direction of seepage and enter the downstream water-sand collection box (16). After the inorganic salts are dissolved, the internal structure of the test sample rock and soil particles changes, thus completing the simulation process of in-situ seepage erosion. Step 5: After the seepage erosion process is completed, the water inlet valve (18) is closed, and the spring assembly (801) in the spring-pressed steel rod is pressed to pop open the end of the press-type steel rod (802), and the spring-pressed steel rod (8) is slid from the inner hole (1702) of the sliding hole (17) to the outer hole (1701), and the spring assembly (801) is pressed again to insert the end of the press-type steel rod (802) into the outer hole (1701), driving the left water-stop rubber (6) and the right water-stop rubber (7) to peel off the left metal gasket (1) and the right metal gasket (2), so that the left metal gasket (1) and the right metal gasket (2) can slide without resistance in the middle pressure sleeve (4), and then a dynamic impact test is carried out to determine the dynamic parameters of the rock and soil particles eroded by seepage.

7. A method for testing in-situ seepage erosion of rock and soil particles according to claim 6, characterized in that: The kinetic parameters include: Strength parameters: stress, strain, strain rate; Seepage parameters: erosion rate, flow velocity.

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