Three-dimensional stress simulation method suitable for pumped storage and water storage roadway of abandoned mine

Abstract

The invention discloses a three-dimensional stress simulation method suitable for a pumped storage and water storage roadway of an abandoned mine, and relates to the technical field of stress simulation of the pumped storage and water storage roadway of the abandoned mine. The method comprises the following steps: firstly, preparing a rock sample, and carrying out a uniaxial compression test on the rock sample to obtain a maximum failure load; the other rock sample is installed in the true triaxial dynamic loading system, and a pre-tightening force is applied to fasten the rock sample; respectively applying the maximum principal stress, the middle principal stress and the minimum principal stress to the rock sample; the three-way principal stress is kept unchanged, single-side dynamic water pressure is applied to the rock sample, and meanwhile a dynamic load is applied to the rock sample by impacting a dowel bar; and finally, observing and recording, recording the obtained stress-strain curve data, stress-time curve data, stress-time curve data and water pressure-time curve data, and performing analysis by combining the recorded curve data and theoretical knowledge of technicians in the field. According to the invention, the real state of the waste mine pumped storage and water storage roadway can be simulated more truly.

Description

Technical Field

[0001] The invention relates to the technical field of stress simulation of abandoned mine pumped storage water storage tunnels, and in particular to a three-dimensional stress simulation method suitable for abandoned mine pumped storage water storage tunnels. Background Art

[0002] With the transformation of energy structure and the demand for sustainable development, pumped storage, as an important energy storage technology, plays an increasingly important role in the energy system. Abandoned mines have become potential application sites for pumped storage projects due to their abundant underground space and stable geological conditions. By transforming abandoned mines into pumped storage power stations, it is not only possible to effectively utilize idle resources, but also to alleviate the pressure on traditional energy supply and improve the stability and dispatching flexibility of the power system. Therefore, abandoned mine pumped storage projects have broad application prospects in the future energy industry.

[0003] In the design and construction of pumped-storage water storage tunnels in abandoned mines, the triaxial stress state borne by the water storage tunnel plays a vital role in its structural stability and water tightness. The triaxial stress state of the water storage tunnel is mainly affected by the combined effects of the geostress field of the rock mass around the mine, the water pressure, and the excavation stress of the mine itself. Therefore, accurately simulating the triaxial stress state in the tunnel, especially the interaction between water pressure and rock mass, is crucial for evaluating the stability and design rationality of the tunnel. Although the existing technology has adopted a variety of rock mechanics test methods, it is often unable to accurately predict the mechanical behavior and failure mode of rock during the water storage process because it cannot fully simulate the complex water-rock-force interaction in the water storage tunnels of abandoned mines.

[0004] This shows that the prior art needs to be further improved. Summary of the invention

[0005] The purpose of the present invention is to provide a three-dimensional stress simulation method suitable for abandoned mine pumped storage water storage tunnels, which can reproduce the complex three-dimensional stress state in the tunnel under a laboratory environment and can more realistically simulate the actual state of abandoned mine pumped storage water storage tunnels.

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

[0007] A three-dimensional stress simulation method applicable to a pumped storage water storage tunnel in an abandoned mine comprises the following steps in sequence:

[0008] a. Prepare a cubic specimen as a rock sample, and perform a uniaxial compression test on the rock sample to obtain the maximum failure load of the rock sample;

[0009] b. Install another rock sample in a true triaxial dynamic loading system, wherein the true triaxial dynamic loading system 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 vertical loading unit comprises an impact force transmission rod; 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 on 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;

[0010] A square groove is provided on the end surface of the front loading head, and a water channel is provided inside the longitudinal loading rod connected to the front loading head. The water channel is connected to a water supply device for providing high-pressure water into the directional groove;

[0011] c. Apply preload force to the rock sample in the true triaxial dynamic loading system to fix it; then apply maximum principal stress σ1, intermediate principal stress σ2, and minimum principal stress σ3 to the rock sample through the vertical loading unit, the transverse loading unit, and the longitudinal loading unit respectively; during the initial loading process, the maximum principal stress σ1 and the intermediate principal stress σ2 are 50% of the maximum destructive load described in step a; the minimum principal stress σ3 is 10% of the maximum destructive load described in step a; after the loading is stable, the maximum principal stress σ1 is adjusted to 80% of the maximum destructive load described in step a;

[0012] d. Keeping the maximum principal stress σ1, the intermediate principal stress σ2, and the minimum principal stress σ3 unchanged, applying a unilateral dynamic water pressure to the rock sample through the front loading head, and applying a dynamic load to the rock sample through the impact force transmission rod;

[0013] e. Observe and record. When the rock sample in the true triaxial dynamic loading system has been destroyed, the test is terminated. The obtained stress-strain curve data, stress-time curve data, stress-time curve data and water pressure-time curve data are recorded, and the failure form of the rock sample is observed;

[0014] f. Combine theoretical knowledge to obtain the destructive strength and damage form of the surrounding rock of abandoned mine pumped storage tunnels at different depths and water pressures.

[0015] The above-mentioned three-dimensional stress simulation method is applicable to the pumped storage water storage tunnel of abandoned mines. In step a, the specification of the rock sample is 150mm×150mm×150mm.

[0016] The above-mentioned three-dimensional stress simulation method applicable to the pumped storage water storage tunnel of abandoned mines, in step b, the vertical loading unit also includes an impact load cylinder, a top loading cylinder, and a top loading head, 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, and the execution ends of the top loading cylinders are fixedly connected by force collecting blocks;

[0017] The top loading head is arranged at the upper inner part of the confining pressure chamber through a vertical loading rod, the impact force transmission rod is coaxially arranged inside 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, thereby applying true triaxial stress.

[0018] The above-mentioned three-dimensional stress simulation method is suitable for abandoned mine pumped storage water storage tunnels. In step c, a preload force in the Z-axis direction is first applied to the rock sample by a vertical loading unit, and the preload force is 10 kN; then, a preload force in the X-axis direction and the Y-axis direction is applied to the rock sample by a longitudinal loading unit and a transverse loading unit, respectively, and the preload force is 10 kN.

[0019] The above-mentioned three-dimensional stress simulation method is applicable to the pumped storage water storage tunnel of abandoned mines. In step d, the dynamic load applied by the impact force transmission rod to the rock sample is 5% of the maximum destructive load in step a.

[0020] The above-mentioned three-dimensional stress simulation method is applicable to the pumped storage water storage tunnel of abandoned mines. In step e, whether the rock sample is damaged is judged by the stress-strain curve and the water pressure-time change.

[0021] The above-mentioned three-dimensional stress simulation method is applicable to the water storage tunnel of abandoned mine pumped storage. When the maximum principal stress value in the stress-strain curve drops or the water pressure value changes suddenly, it means that the rock sample has been damaged.

[0022] Compared with the prior art, the present invention brings the following beneficial technical effects:

[0023] The present invention provides a three-dimensional stress simulation method suitable for abandoned mine pumped storage water storage tunnels. Compared with traditional indoor uniaxial crushing tests and conventional triaxial crushing tests, it can more realistically reflect the stress path during the water storage process of the actual water storage tunnel; compared with true triaxial creep tests, it can greatly reduce the number of test specimens and thus obtain more test data in the same time.

[0024] The present invention provides a three-dimensional stress simulation method suitable for abandoned mine pumped storage water storage tunnels. By keeping the maximum principal stress σ1, the intermediate principal stress σ2, and the minimum principal stress σ3 unchanged, a unilateral dynamic water pressure is applied to the rock sample through a front loading head, and a dynamic load is applied to the rock sample through an impact force transmission rod. In this way, the stress environment in the actual water storage tunnel during water storage can be more realistically reflected, and the three-dimensional stress state in actual working conditions can be understood in a laboratory environment, providing a certain reference basis for the mechanical behavior and failure mode of rock in actual working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described below in conjunction with the accompanying drawings.

[0026] Figure 1 It is a flow chart of a three-dimensional stress simulation method applicable to abandoned mine pumped storage water storage tunnels of the present invention;

[0027] Figure 2 It is a schematic diagram of the uniaxial compression force direction of the rock sample of the present invention;

[0028] Figure 3 It is a schematic diagram of the three-dimensional stress of the rock sample of the present invention;

[0029] Figure 4 It is a uniaxial compression curve diagram of the rock sample of the present invention;

[0030] Figure 5 It is a schematic diagram of the true triaxial seepage disturbance loading stress path of the rock sample of the present invention;

[0031] Figure 6 It is a true triaxial seepage disturbance loading stress-time curve diagram of the rock sample of the present invention;

[0032] Figure 7 The true triaxial seepage disturbance loading water pressure-time curve diagram of the standard rock sample of the rock sample of the present invention;

[0033] Figure 8 It is a three-dimensional diagram of the combined structure of the confining pressure chamber and related parts of the present invention;

[0034] Fig. 9 for Figure 8 A vertical section view of the composite structure;

[0035] In the figure:

[0036] 1. Top cover, 2. Clamp, 3. Clamp, 4. Square bottom plate, 5. Stroke cylinder, 6. Impact force transmission rod, 7. Vertical loading rod, 8. Transverse loading rod, 9. Longitudinal loading rod, 10. Reset spring, 11. Annular limit part, 12. Base, 13. Cylinder body, 14. Positioning column, 15. Top loading head, 16. Front loading head, 17. Rear loading head, 18. Waterway, 19. Rock sample, 20. Square groove. DETAILED DESCRIPTION

[0037] The present invention proposes a three-dimensional stress simulation method suitable for abandoned mine pumped storage water storage tunnels. In order to make the advantages and technical solutions of the present invention clearer and more specific, the present invention is further described below in conjunction with specific embodiments.

[0038] The true three-axis dynamic loading system required by the present invention 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 a feeding and discharging platform; Figure 8 and Fig. 9 As shown, the present invention mainly introduces the structure of the confining pressure chamber and its related components.

[0039] The confining pressure chamber is arranged on the workbench through a liftable linear transfer mechanism. Specifically, the confining pressure chamber includes a base 12, a cylinder body 13 and a top cover 1. The base 12 is fixed to the upper surface of the linear transfer mechanism. The base 12 is a truncated cone structure. The cylinder body 13 is a cylindrical structure with openings at both ends and is vertically arranged above the base 12. The upper end of the cylinder body 13 is fixedly sealed with the top cover 1, and the lower end of the cylinder body 13 is sealed with the base 12 and is fixedly connected to the base 12 through a clamping assembly.

[0040] The confining pressure chamber is connected to the water supply device through a pipeline. After the confining pressure chamber is filled with high-pressure water, the rock sample 19 can simulate the uniaxial loading test under the action of dynamic and static load confining pressure.

[0041] The clamping assembly includes a clamping flap 2 and a clamping hoop 3. There are four clamping flaps 2. The clamping flap 2 is in the shape of a 1 / 4 arc with a groove on the inner side. The four clamping flaps 2 are spliced ​​into a circular ring and clamped at the connection between the base 12 and the lower end of the barrel 13. The clamping hoop 3 is sleeved on the outside of the four clamping flaps 2. The clamping force of the clamping hoop 3 tightens the four clamping flaps 2 to fix the lower end of the barrel 13 to the base 12.

[0042] The vertical loading unit includes an impact load cylinder, a top loading cylinder, a top loading head 15 and an impact force transmission rod 6. The impact load cylinder is vertically fixedly installed at the center position of the top of the main frame. There are four top loading cylinders. The four top loading cylinders 52 are vertically and regularly arranged around the impact load cylinder. The impact load cylinder and the top loading cylinder are both supplied with oil and returned with oil by the hydraulic station.

[0043] The top loading head 15 is arranged at the upper inner part of the confining pressure chamber through the vertical loading rod 7. The vertical loading rod 7 has an impact force transmission rod 6 coaxially arranged therein. The impact force transmission rod 6 is slidably matched with the vertical loading rod 7 outside thereof. The impact load cylinder 51 applies an impact load to the top loading head 15 through the impact force transmission rod 6. Furthermore, the top loading head 15 applies a vertical static load to the rock sample 19, and the impact force transmission rod 6 applies a vertical impact load to the rock sample 19 through the top loading head 15.

[0044] The lateral loading unit includes a loading cylinder, a left loading head and a right loading head located on the left and right sides. The left loading cylinder and the right loading cylinder are symmetrically fixed on the left and right sides of the main frame. The left loading cylinder and the right loading cylinder are both supplied with oil and returned with oil by the hydraulic station.

[0045] The left loading head and the right loading head are both relatively arranged in the confining pressure chamber through a transverse loading rod 8. Specifically, the two transverse loading rods 8 are coaxially and relatively penetrated on the left and right walls of the confining pressure chamber, and each transverse loading rod 8 slides with the side wall of the confining pressure chamber 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 8, respectively. The two transverse loading rods 8 are located at one end outside the confining pressure chamber, and are respectively plugged and matched with the two transverse external loading heads at the end of the transverse force transmission rod. The left loading cylinder and the right loading cylinder respectively drive the two transverse external loading heads 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 by the transverse loading rod 8 to load the rock sample 19 laterally.

[0046] The vertical loading unit includes an impact force transmission rod, and the longitudinal loading unit includes a front loading cylinder, a rear loading cylinder, a front loading head 16 and a rear loading head 17. The front loading head 16 and the rear loading head 17 are both relatively arranged in the confining pressure chamber through a longitudinal loading rod 9. 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 applied to the front loading head and the rear loading head synchronously respectively.

[0047] A square groove 20 is provided on the end surface of the front loading head, and a water channel 18 is provided inside the longitudinal loading rod connected to the front loading head. The water channel is connected to a water supply device for providing high-pressure water into the directional groove;

[0048] The positioning column 14 is vertically fixed to the center of the bottom of the square bottom plate 4, and its lower end can be inserted into the positioning hole to fix the square bottom plate 4 to the workbench. Four stroke cylinders 5 are respectively installed on the upper surface of the four corners of the square bottom plate 4, and the four stroke cylinders 5 respectively drive four rollers to be stored inside the square bottom plate 4. The square bottom plate 4 is lowered until its bottom is in contact with the surface of the workbench, the positioning column is located in the positioning hole of the workbench, and the square bottom plate 4 is fixed to the workbench.

[0049] A reset spring 10 is sleeved on each of the two transverse loading rods 8 and the two longitudinal loading rods 9. All the reset springs 10 are located outside the confining pressure chamber. The transverse loading rods 8 and the longitudinal loading rods 9 are provided with an annular limiting portion 11 for limiting the reset spring 10. In the unloaded state, the reset spring 10 drives the corresponding transverse loading rod 8 or longitudinal loading rod 9 to move outward, so that the left loading head, the right loading head, the front loading head and the rear loading head are separated from the rock sample. Before placing the rock sample inside the confining pressure chamber, the left loading head, the right loading head, the front loading head and the rear loading head are in an outward expansion state, which is convenient for placing the rock sample inside the confining pressure chamber. The rock sample of the present invention adopts a cubic specimen.

[0050] The following is a detailed description of the three-dimensional stress simulation method applicable to abandoned mine pumped storage water storage tunnels of the present invention.

[0051] A three-dimensional stress simulation method for pumped storage tunnels in abandoned mines, such as Figure 1 As shown, the specific steps include:

[0052] The first step is to prepare several cube-shaped rock samples of the same size and shape; obtain natural rock samples from the engineering site, and process them into a cube shape through drilling, cutting and grinding processes. The specifications of the rock samples are 150mm×150mm×150mm, the length error of the rock samples does not exceed 0.1mm, and the allowable deviation of the unevenness of the two end surfaces of the rock samples is ±0.02mm. The acoustic wave detection system is used to select rocks with similar wave velocities as test rock samples; when necessary, the loading direction can be identified by marking the rock samples, such as the loading in the X-axis direction, the Y-axis direction and the Z-axis direction involved in the present invention.

[0053] The second step is to select one of the rock samples and perform a uniaxial compression test on it (such as Figure 2 As shown in the figure, the maximum failure load is obtained to provide a reference for subsequent loading. The obtained uniaxial compression stress-strain curve is shown in the figure Figure 4 shown.

[0054] Step 3: Select another rock sample and install it in the confining pressure chamber, and apply preload force to fix the rock sample; the loading method is as follows: Figure 3 As shown, Figure 3 Where σd and σs are dynamic load and dynamic water pressure respectively. The loading path is as follows Figure 5 As shown, the rock sample is a regular cube, ensuring that it can be subjected to true triaxial test. The cube rock sample is fixed, and the preload applied to the rock sample is 10kN.

[0055] like Figure 3As shown, the cubic rock sample is independently loaded with true triaxial stresses σ1, σ2, and σ3, where σ1 is the maximum principal stress, σ2 is the intermediate principal stress, and σ3 is the minimum principal stress. σ1, σ2, and σ3 are loaded to 50% of the initial principal stress level. The stress loading control method is adopted, and the cubic rock sample is synchronously and independently loaded with the loading method recommended in the "Rock True Triaxial Test Code" to maintain the true triaxial stresses σ1, σ2, and σ3 until these three stresses reach the set initial principal stress level.

[0056] Step 4: Keep the intermediate principal stress σ2 unchanged and load the maximum principal stress σ1 until the maximum principal stress σ1 reaches the set maximum principal stress level; use the stress loading control method to load to the maximum principal stress σ1 at the same loading rate as the third step until the set maximum principal stress level is reached; wherein the set maximum principal stress level is 80% of the maximum destructive load of the rock sample measured in the second step.

[0057] The fifth step is to keep the maximum principal stress σ1, the intermediate principal stress σ2, and the minimum principal stress σ3 unchanged, and apply appropriate unilateral dynamic water pressure to the rock sample through the front loading head (such as sinusoidal wave loading, the trough is 0.1MPa, the peak is 2MPa, and the frequency is 0.01Hz) (can be changed according to the test needs), and at the same time as the water pressure is applied, the impact force transmission rod is loaded to apply a dynamic load to the rock sample (such as sinusoidal wave loading, the trough is 0, the peak is 5% of the maximum destructive load of the rock sample obtained in the second step, and the frequency is 5Hz) (can be changed according to the test needs).

[0058] Step 6: Observe and record. Record the stress-strain curve data obtained during the test. Determine whether the stress-strain curve, strain-time curve, and water pressure test curve data are needed according to the research situation. The true triaxial strength of the test can be quickly seen from the stress-time curve data. The strain-time curve data is helpful for the actual deformation and damage of the project. The stress-strain curve data can reflect the overall mechanical properties of the test rock, and the water pressure-time curve can reflect the changes in the internal cracks of the rock.

[0059] When the rock sample in the true triaxial dynamic loading system has been destroyed, the test is terminated and the destruction form of the rock sample is observed; preferably, whether the rock sample is destroyed is judged by observing the stress-strain curve and the time change of water pressure.

[0060] Step 7. Combine theoretical knowledge to obtain the destruction strength and destruction form of the surrounding rock of abandoned mine pumped storage tunnels at different depths and water pressures.

[0061] The loading path and the stress-time curve of the cyclic loading obtained in this embodiment are as follows: Figure 6 As shown, the water pressure-time curve is as follows Figure 7 shown.

[0062] To sum up, the present invention can more realistically simulate the stress process of the surrounding rock during the water storage process in the water storage tunnel of an abandoned mine. Although the present invention focuses on abandoned mines, it is well known to those skilled in the art that it can also be applied to other similar scenarios (such as underground reservoirs, tunnel surrounding rocks, etc.) or under different geological conditions.

[0063] Parts not described in the present invention can be implemented by referring to the existing technology.

[0064] Those skilled in the art should recognize that the above embodiments are only used to illustrate the present application and are not used as limitations on the present application. As long as they are within the spirit of the present application, appropriate changes and modifications to the above embodiments are within the scope of protection of the claims of the present application.

Claims

1. A three-dimensional stress simulation method suitable for abandoned mine pumped storage water storage tunnels, characterized in that: The following steps are included in sequence: a. Prepare a cubic specimen as a rock sample, and perform a uniaxial compression test on the rock sample to obtain the maximum failure load of the rock sample; b. Install another rock sample in a true triaxial dynamic loading system, wherein the true triaxial dynamic loading system 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 vertical loading unit comprises an impact force transmission rod; 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 on 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, and a water channel is provided inside the longitudinal loading rod connected to the front loading head. The water channel is connected to a water supply device for providing high-pressure water into the directional groove; c. Apply preload force to the rock sample in the true triaxial dynamic loading system to fix it; then apply maximum principal stress σ1, intermediate principal stress σ2, and minimum principal stress σ3 to the rock sample through the vertical loading unit, the transverse loading unit, and the longitudinal loading unit respectively; during the initial loading process, the maximum principal stress σ1 and the intermediate principal stress σ2 are 50% of the maximum destructive load described in step a; the minimum principal stress σ3 is 10% of the maximum destructive load described in step a; after the loading is stable, the maximum principal stress σ1 is adjusted to 80% of the maximum destructive load described in step a; d. Keeping the maximum principal stress σ1, the intermediate principal stress σ2, and the minimum principal stress σ3 unchanged, applying a unilateral dynamic water pressure to the rock sample through the front loading head, and applying a dynamic load to the rock sample through the impact force transmission rod; e. Observe and record. When the rock sample in the true triaxial dynamic loading system has been destroyed, the test is terminated. The obtained stress-strain curve data, stress-time curve data, stress-time curve data and water pressure-time curve data are recorded, and the failure form of the rock sample is observed; f. Combine theoretical knowledge to obtain the destructive strength and damage form of the surrounding rock of abandoned mine pumped storage tunnels at different depths and water pressures.

2. A three-dimensional stress simulation method for abandoned mine pumped storage water tunnels according to claim 1, characterized in that: In step a, the specification of the rock sample is 150mm×150mm×150mm.

3. A three-dimensional stress simulation method for abandoned mine pumped storage water tunnel according to claim 1, characterized in that: In step b, the vertical loading unit further comprises an impact load cylinder, a top loading cylinder, and a top loading head. The impact load cylinder is vertically arranged at the top center of the main frame. There are multiple top loading cylinders, and all top loading cylinders are regularly arranged around the impact load cylinder. The execution ends of the top loading cylinders are fixedly connected by force collecting blocks. The top loading head is arranged at the upper inner part of the confining pressure chamber through a vertical loading rod, the impact force transmission rod is coaxially arranged inside 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, thereby applying true triaxial stress.

4. A three-dimensional stress simulation method for abandoned mine pumped storage water tunnel according to claim 1, characterized in that: In step c, a preload force of 10 kN is first applied to the rock sample in the Z-axis direction by the vertical loading unit; and then a preload force of 10 kN is applied to the rock sample in the X-axis direction and the Y-axis direction by the longitudinal loading unit and the transverse loading unit respectively.

5. The three-dimensional stress simulation method for abandoned mine pumped storage water tunnel according to claim 1 is characterized by: In step d, the dynamic load applied to the rock sample by the impact force transmission rod is 5% of the maximum destructive load in step a.

6. A three-dimensional stress simulation method for abandoned mine pumped storage water tunnels according to claim 1, characterized in that: In step e, whether the rock sample is damaged is determined by the stress-strain curve and the water pressure-time variation.

7. A three-dimensional stress simulation method for abandoned mine pumped storage water tunnels according to claim 6, characterized in that: When the maximum principal stress value in the stress-strain curve drops or the water pressure value changes suddenly, it means that the rock sample has been damaged.

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