A physical simulation device and method for disaster incubation of dangerous rock mass under acid rain wet-dry alternation

Abstract

The acid rain dry-wet alternating dangerous rock mass disaster gestation physical simulation device belongs to the technical field of geotechnical engineering, and comprises a leaching tank, a model support, a dangerous rock mass model, a liquid preparation tank, an acid rain leaching device and a whole-process real-time monitoring system; the leaching tank is composed of a tank body and a tank cover, the tank body is provided with a detachable tank cover on the open end, and the tank cover is connected with the acid rain circulating leaching device; the model support is placed in the inner cavity of the tank body; the dangerous rock mass model adopts three-dimensional scanning and 3D printing technology to identify and print the geometric information of the on-site dangerous rock mass, and the mud cementing material mainly composed of weathering products at the structural surface of the on-site dangerous rock mass is used to bond the components; and the whole-process real-time monitoring system comprises video monitoring, acoustic emission monitoring, crack force monitoring, crack opening monitoring and ion concentration monitoring. The acid rain leaching + dry-wet alternating dangerous rock mass disaster gestation process is simulated, and the whole process of the macroscopic and microscopic breakage, disaster initiation and collapse of the dangerous rock mass clavicle segment is monitored in real time.

Description

Technical Field

[0001] This invention belongs to the field of geotechnical engineering technology, and specifically relates to a device and method for intelligent simulation of the catastrophic formation of unstable rock masses under alternating wet and dry conditions of acid rain, using multi-physics fields at room temperature. Background Technology

[0002] With the increasing severity of environmental pollution and the frequent occurrence of acid rain, which is rich in acidic corrosive substances, the alternating wet and dry effects of acid rain and natural wind drying on unstable rock masses on slopes will, on the one hand, corrode the unstable rock mass, promote the penetration of fine pores and the expansion of cracks inside the rock, thereby weakening the mechanical properties of the unstable rock mass; on the other hand, in the natural acid rain environment, acid rain erosion will scour and corrode the anchoring sections of the unstable rock mass as well as the structural surfaces such as cracks, joints, and bedding planes, further weakening the cementation and strength of the anchoring sections and the natural structural surfaces of the rock mass, accelerating the rupture of the anchoring sections and structural surfaces of the unstable rock mass, and thus inducing the collapse and instability of the unstable rock mass. Due to the regional differences in acid rain climate and the varying potential hazards of unstable rock masses, as well as the concealed nature of the locking sections of natural unstable rock masses, it is difficult to predict whether unstable rock masses will collapse in the short term and the timing of such collapses. This makes it difficult to conduct long-term, systematic field tests and follow-up studies. Compared to outdoor tests, indoor tests make it easier to control environmental variables and the potential hazards of unstable rock masses (the length and characteristics of the locking sections of unstable rock masses are controllable), providing an effective research approach for studying the above issues.

[0003] The current experimental research on unstable rock masses has the following problems:

[0004] 1. There is a lack of indoor physical simulation devices for acid rain erosion and alternating wet and dry conditions that induce disasters in unstable rock masses;

[0005] 2. There is a lack of effective monitoring information on internal fractures in rock masses for research on the gestation mechanism of dangerous rock mass disasters;

[0006] 3. The formation, propagation, and penetration process of micro-cracks in the locked section of the unstable rock mass are unclear;

[0007] 4. In response to the above problems, there is an urgent need to propose a physical simulation device and method for the gestation of dangerous rock mass disasters under alternating wet and dry conditions of acid rain, so as to solve the problems of simulating the gestation of dangerous rock mass disasters under complex environments and the lack of clear disaster precursors, and to reveal the gestation process and mechanism of dangerous rock mass disasters. Summary of the Invention

[0008] The purpose of this invention is to provide a physical simulation device and method for the catastrophic formation of unstable rock masses under alternating acid rain and wet / dry conditions. By using 3D scanning and 3D printing technology on-site unstable rock masses, a scaled-down model of the unstable rock mass is printed. This model is then bonded and assembled using a clayey cementitious material, primarily composed of natural weathering products from the structural surfaces of the unstable rock mass, to form a model for leaching. During the leaching process, an acid rain circulating leaching system is used to adjust the leaching intensity to simulate natural conditions. After the leaching test, the unstable rock mass model is transferred to a constant-temperature drying oven for drying. This method maximizes the reproduction of the original state of the unstable rock mass, reducing the difference between indoor experiments and natural conditions.

[0009] A physical simulation device for the catastrophic formation of unstable rock masses under alternating wet and dry acid rain conditions includes a leaching chamber, a solution preparation tank, a model platform, an acid rain circulating leaching system, and a real-time monitoring system.

[0010] The etching chamber consists of a chamber body and a cover. A removable cover is installed at the open end of the chamber body. The outside of the cover is connected to an external solution tank via an acid rain circulating etching system. The solution tank is equipped with a solution NO3. - Ions, SO4 2- The ion concentration and pH value monitoring device is an ion meter. A monitoring system is installed inside the leaching chamber. The model stage is placed in the middle of the cavity inside the leaching chamber.

[0011] The model platform is an integral loading device cast from a single piece of PAM board material.

[0012] The acid rain circulating leaching system consists of two circulating water pumps connected to a leaching tank and a solution preparation tank via inlet pipes. One of the circulating water pumps is connected to a spray pipe fixed inside the leaching tank via a circulating leaching inlet valve on the leaching tank cover. The other circulating water pump is connected to the leaching tank and the solution preparation tank via a circulating leaching outlet valve on the leaching tank cover. The inside of the circulating leaching outlet valve on the leaching tank cover is connected to the solution level below the leaching tank via an inlet pipe, and the outside is connected to the solution level below the solution level in the solution preparation tank via an inlet pipe.

[0013] The spray pipe mainly consists of an atomizing spray head and an infusion pipe. The atomizing spray head can adjust the solution flow rate and atomization degree.

[0014] The real-time monitoring system mainly consists of a video monitoring system, an acoustic emission monitoring system, a miniature rebar gauge, a miniature crack gauge, and an ion meter. The cameras in the video monitoring system are installed in the frontal, lateral, and isometric views of the unstable rock mass model to monitor the unstable rock mass's locking section, the unstable rock mass itself, and the model as a whole. The acoustic emission monitoring system includes acoustic emission sensors distributed at the upper right, lower right, and locking sections of the unstable rock mass model to monitor acoustic signals generated by microscopic damage within the model. The miniature rebar gauge is embedded inside the unstable rock mass model, spanning both sides of the main control surface, to monitor crack forces generated during the collapse. The miniature crack gauge is fixed to the upper end of the unstable rock mass model, spanning both sides of the main control surface, to monitor crack opening during the collapse. The ion meter is attached to a solution preparation tank for preparing the leaching solution and monitoring its pH and NO3 levels. - Ions, SO4 2- Ion concentration.

[0015] The method for using the physical simulation device for the catastrophic formation of unstable rock masses under alternating wet and dry conditions of acid rain includes the following steps:

[0016] Step 1: Before the leaching test begins, the pre-embedded monitoring devices, namely micro steel bar gauges and micro crack gauges, are pre-installed on the unstable rock mass model. Then, muddy cementitious material with natural weathering products at the structural surface of the unstable rock mass as the main component is used to bond and assemble the printed unstable rock mass model components to form an unstable rock mass model. After the unstable rock mass model is assembled, the acoustic emission sensor is connected and fixed in the predetermined position.

[0017] Step 2: Place the processed unstable rock mass model on the model platform, then place the model platform together with the unstable rock mass model in the middle of the leaching box, and adjust the position of the unstable rock mass model. When adjusting the unstable rock mass model, it is necessary to ensure that the front and side of the unstable rock mass model are aligned with the monitoring cameras in the front and side directions of the video monitoring group to ensure the monitoring effect.

[0018] Step 3: After the unstable rock mass model is placed, the leaching solution is prepared in the mixing tank using an ion meter to ensure the NO3 content in the leaching solution is within acceptable limits. - Ions, SO4 2- Once the ion concentration and pH value reach the target values ​​of the test plan, ensure that the ion meter is always on to record the changes in ion concentration of the leaching solution during the leaching process. Then check the connection between the circulating water pump and the delivery pipe, and ensure that the delivery pipe in the solution tank is below the liquid level in the solution tank. Then connect the circulating leaching inlet valve on the leaching tank cover to the spray pipe inside the leaching tank. At the same time, adjust the delivery pipe connected to the circulating leaching outlet valve inside the leaching tank so that the delivery pipe is at the bottom of the leaching tank.

[0019] Step 4: Connect the power supply and turn on the circulating water pump connected to the circulating leaching inlet valve on the leaching chamber cover for pre-leaching. The liquid level in the leaching chamber should exceed the liquid delivery pipe connected to the circulating leaching outlet valve.

[0020] Step 5: Turn on the monitoring camera and acoustic emission device to monitor the destruction process of the unstable rock mass model during the leaching process from both macroscopic and microscopic perspectives. Set the leaching time and intensity, and turn on the circulating water pump connected to the circulating leaching outlet valve on the leaching box cover to carry out circulating leaching.

[0021] Step 6: After the predetermined leaching time is reached, turn off the circulating water pump connected to the circulating leaching inlet valve, and keep the circulating water pump connected to the circulating leaching outlet valve running to drain the accumulated solution in the leaching tank; then remove the acoustic emission sensor, take out the unstable rock mass model, and let it stand to drain the residual leaching solution on the surface of the unstable rock mass model. After completion, copy the monitoring data from the camera inside the video monitoring system, the monitoring data from the acoustic emission monitoring system, the monitoring data from the micro rebar gauge, the monitoring data from the micro crack gauge, and the solution ion concentration change data recorded by the ion meter during the leaching process; remove the stage placed in the leaching tank from the leaching tank, and then pour out the remaining residual solution from the leaching tank to clean it up. The leaching test is now complete.

[0022] Step 7: Transfer the unstable rock mass model to a constant temperature drying oven for constant temperature drying treatment, and then repeat steps 1 to 6 above to conduct the next leaching test.

[0023] Step 8: Repeat steps 1 to 7 above, subjecting the rock mass to acid rain erosion and drying N times until the rock mass is destroyed.

[0024] Step 9, set the NO3 concentration for different leaching solutions - Ions, SO4 2- Repeat steps 1 to 8 above, adjusting ion concentration, pH, leaching intensity, and leaching time.

[0025] The beneficial effects of this invention are mainly reflected in:

[0026] 1. The experimental device of this invention has the feature of simulating the disaster process of unstable rock mass, and can simulate the evolution process of unstable rock mass disaster under the action of acid rain erosion with different erosion intensities;

[0027] 2. The experimental apparatus of the present invention has an acoustic emission device arranged on the unstable rock mass model, which can collect the acoustic signals generated by the test specimen during the leaching process and collect effective information on the gestation process of the unstable rock mass disaster, so as to facilitate the experimental analysis after the test.

[0028] 3. The experimental device of the present invention is equipped with a high-definition camera to monitor the generation, propagation and penetration of micro-cracks in the locking section of the unstable rock mass during the test of the test specimen;

[0029] 4. The device is mainly made of PAM board to facilitate experimental observation. The main body of the test specimen is made by proportionally reducing the size of the unstable rock mass on site using three-dimensional scanning and 3D printing technology. The cementing material used in the unstable rock mass locking section is a muddy cementing material with weathering products on site as the main component, so as to improve the similarity between the test environment and the original environment. Attached Figure Description

[0030] Figure 1 Front view of the physical simulation device for the catastrophic formation of unstable rock masses under alternating acid rain and dry / wet conditions according to the present invention;

[0031] Figure 2 Cross-sectional view of the physical simulation device for the catastrophic formation of unstable rock masses under alternating acid rain and dry / wet conditions of this invention (I-I);

[0032] Figure 3 Detailed external view of the acid rain cyclic leaching system of the physical simulation device for the catastrophic formation of unstable rock masses under alternating wet and dry conditions of the present invention;

[0033] Figure 4 Detailed drawing of the spray pipe of the physical simulation device for the catastrophic formation of unstable rock masses under alternating acid rain and dry / wet conditions of this invention;

[0034] Figure 5 Front view of the unstable rock mass model in the physical simulation device for the catastrophic formation of unstable rock masses under alternating acid rain and dry / wet conditions of this invention;

[0035] Figure 6 Top view of the unstable rock mass model in the physical simulation device for the catastrophic formation of unstable rock masses under alternating acid rain and dry / wet conditions of this invention;

[0036] 1-Leaching chamber, 101-Leaching chamber cover, 102-Leaching chamber body, 2-Liquid preparation tank, 3-Ion meter, 4-Circulating leaching outlet valve, 401-Circulating leaching outlet valve inlet, 402-Circulating leaching outlet valve outlet, 5-Circulating leaching inlet valve, 501-Circulating leaching inlet valve inlet, 502-Circulating leaching inlet valve outlet, 6-Infusion pipe, 7-Video monitoring system, 701-Isometric camera, 702-Side camera, 703-Front-view camera, 8-Spray pipe, 801 - Sprayer inlet pipe, 802 - Atomizing spray head, 9 - Acoustic emission monitoring system, 10 - Model platform, 11 - Dangerous rock mass model, 1101 - Dangerous rock mass, 1102 - Main control structural surface of dangerous rock mass, 1103 - Model bedding, 1104 - Micro crack gauge, 1105 - Micro rebar gauge, 12 - Circulating water pump, 1201 - Circulating water pump inlet, 1202 - Circulating water pump outlet, 13 - Circulating water pump, 1301 - Circulating water pump inlet, 1302 - Circulating water pump outlet.

[0037] Specific Implementation Cases

[0038] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0039] like Figures 1 to 3 As shown, the physical simulation device for the catastrophic formation of unstable rock masses under alternating wet and dry acid rain includes a leaching tank 1, a solution preparation tank 2, a model platform 10, an acid rain circulating leaching system, and a real-time monitoring system. The leaching tank 1 consists of a tank body 102 and a lid 101. A detachable lid 101 is installed at the open end of the tank body 102. The lid 101 is connected to the solution preparation tank 2 on the outside through the acid rain circulating leaching system. The solution preparation tank 2 is equipped with a solution NO3. - Ions, SO4 2- The ion concentration and pH monitoring device is an ion meter 12. A video monitoring system 7 is installed inside the leaching chamber 102. The model platform 10 is placed in the middle of the inner cavity of the leaching chamber 102. The dimensions of the leaching chamber are 500mm in length × 500mm in width × 500mm in height, and it is made of PEM board material. The dimensions of the model platform 10 are 300mm × 300mm × 200mm, and it is also made of PEM board material. This invention uses 3D scanning and 3D printing technology to proportionally reduce the size of each component of the unstable rock mass model 11. The model components are then bonded and assembled using a clay cementing material mainly composed of weathering products from the site. During the leaching process, an acid rain circulating leaching system is used to adjust the leaching intensity to simulate natural conditions. The above method restores the original state of the unstable rock mass to the greatest extent and reduces the difference between the indoor test and the natural state.

[0040] The acid rain circulating leaching system includes a solution tank 2, a circulating water inlet pump 12, a circulating water outlet pump 13, a circulating leaching outlet valve 4, a circulating leaching inlet valve 5, a delivery pipe 6, and a spray pipe 8. The delivery pipe 6 is a pipe connecting the various components of the acid rain circulating leaching system. Both the delivery pipe 6 and the spray pipe 8 are made of PVC. The spray pipe 8 is located inside the leaching tank 102 near the tank opening, and is fixed in a ring to the tank wall of the tank 2. It is connected to the quick-connect fitting inside the tank cover 101 via the spray pipe inlet pipe 801 to the outlet 502 of the circulating leaching inlet valve. On the top, the external circulating leaching inlet valve 5 of the tank cover 102 is connected to the outlet 1202 of the circulating water pump through the inlet pipe 6, and then connected to the inlet pipe 6 that extends into the mixing tank 2 through the inlet 1201 of the circulating water pump; the inlet 1301 of the circulating water pump 13 is connected to the outlet 402 of the circulating leaching outlet valve through the inlet pipe 6, the inlet 401 of the circulating leaching outlet valve is connected to the inlet pipe 6 that extends into the bottom of the leaching tank 102, and the outlet 1302 of the circulating water pump 13 is connected to the inlet pipe 6 that extends into the mixing tank 2.

[0041] The model platform 10 is an integral loading device made of PAM board material.

[0042] The spray pipe 8 is mainly composed of an atomizing spray head 802 and a liquid delivery pipe 6. The atomizing spray head can adjust the solution flow rate and atomization degree, and is connected to the outlet 502 of the circulating leaching inlet valve through the spray pipe inlet pipe.

[0043] The real-time monitoring system mainly consists of a video monitoring system 7, an acoustic emission monitoring system 9, a miniature rebar gauge 1105, a miniature crack gauge 1104, and an ion meter 3. The video monitoring system 7 includes cameras fixed to the frontal view of the rock mass model 11: a frontal view camera 703, a side view camera 702, and an isometric view camera 701, used to monitor the rock mass locking section, the rock mass itself, and the model as a whole. The acoustic emission monitoring system 9 contains acoustic emission sensors distributed at the upper right, lower right, and rock mass locking sections of the rock mass model 11, used to monitor microscopic damage within the rock mass model 11. The system generates acoustic signals; the micro-reinforcement gauge 1105 is embedded inside the unstable rock mass model, spanning both sides of the main control structural surface 1102 of the unstable rock mass, and is used to monitor the crack force generated during the collapse of the unstable rock mass; the micro-crack gauge 1104 is fixed to the upper end of the unstable rock mass model, spanning both sides of the main control structural surface 1102 of the unstable rock mass, and is used to monitor the crack opening generated during the collapse of the unstable rock mass; the ion meter 3 is associated with the solution preparation tank 2, and is used to prepare the leaching solution and monitor the pH value and NO3 of the leaching solution. - Ions, SO4 2- Ion concentration.

[0044] The method for using the physical simulation device for the catastrophic formation of unstable rock masses under alternating wet and dry conditions with acid rain includes the following steps:

[0045] Step 1: Before the leaching test begins, the pre-embedded monitoring devices, namely the micro steel bar gauge 1105 and the micro crack gauge 1104, of the unstable rock mass model 11 are pre-embedded and installed. Then, the printed unstable rock mass model components are bonded and assembled using a muddy cementitious material with natural weathering products at the structural surface of the unstable rock mass as the main component to form the unstable rock mass model 11. After the unstable rock mass model 11 is assembled, the acoustic emission sensors of the acoustic emission monitoring system 9 are connected and fixed in the predetermined positions.

[0046] Step 2: Place the processed unstable rock mass model 11 on the model platform 10, then place the model platform 10 together with the unstable rock mass model 11 in the middle of the leaching box 102, and adjust the position of the unstable rock mass model 11. When adjusting the unstable rock mass model 11, it is necessary to ensure that the front and side of the unstable rock mass model are aligned with the monitoring cameras of the front-view camera 703 and the side-view camera 702 of the video monitoring group 7 to ensure the monitoring effect.

[0047] Step 3: After the unstable rock mass model 11 is placed, the leaching solution is prepared in the mixing tank 2 using the ion meter 3, so that the NO3 in the leaching solution... - Ions, SO4 2- When the ion concentration reaches 0.001 mol / L and the pH value reaches 3, ensure that the ion meter 3 is always on to record the change data of ion concentration of the leaching solution during the leaching process. Then check the connection between the circulating water pump 12, circulating water pump 13, circulating leaching outlet valve 4, circulating leaching inlet valve 5, delivery pipe 6, and spray pipe 8, and ensure that the delivery pipe 6 in the solution tank 2 is below the liquid surface in the solution tank 2. Then connect the circulating leaching inlet valve 5 on the leaching box cover 101 and the spray pipe 8 in the leaching box body 102. At the same time, adjust the delivery pipe 6 connected to the circulating leaching outlet valve 4 in the leaching box body 102 so that the delivery pipe 6 is at the bottom of the leaching box body 1.

[0048] Step 4: Connect the power supply and turn on the circulating water pump 12 connected to the circulating leaching inlet valve 5 on the leaching chamber cover 101 to perform pre-leaching. The liquid level in the leaching chamber 1 exceeds the liquid delivery pipe 6 inside the chamber.

[0049] Step 5: Turn on the video monitoring system 7 and the acoustic emission monitoring system 9 to monitor the destruction process of the unstable rock mass model 11 during the leaching process from both macroscopic and microscopic perspectives. Set the leaching time to 1 day and the leaching intensity to 1 L / min. Turn on the circulating water pump 13 connected to the circulating leaching outlet valve 4 on the leaching box cover 101 to carry out circulating leaching.

[0050] Step 6: After the predetermined leaching time is reached, shut off the circulating water pump 12 connected to the circulating leaching inlet valve 5, and keep the circulating water pump 13 connected to the circulating leaching outlet valve 4 running to drain the accumulated solution in the leaching chamber 102; then remove the acoustic emission sensor of the acoustic emission monitoring system 9, take out the unstable rock mass model 11, and let it stand to drain the residual leaching solution on the surface of the unstable rock mass model 11. After completion, copy the monitoring data from the camera inside the video monitoring system 7, the monitoring data from the acoustic emission monitoring system 9, the monitoring data from the micro rebar gauge 1105, the monitoring data from the micro crack gauge 1104, and the solution ion concentration change data recorded by the ion meter 3 during the leaching process; remove the platform 10 placed in the leaching chamber 102 from the leaching chamber 102, and then clean the remaining residual solution in the leaching chamber 102. The leaching test is then completed.

[0051] Step 7: Transfer the removed unstable rock mass model 11 to a constant temperature drying oven for drying at 35°C, and then repeat steps 1 to 6 above to conduct the next leaching test.

[0052] Step 8: Repeat steps 1 to 7 above, and carry out acid rain erosion and drying N times until the dangerous rock mass 1101 is destroyed;

[0053] Step 9, set the NO3 in the leaching solution - Ions, SO4 2- The steps 1 to 8 above were repeated with an ion concentration of 0.0001, a pH of 4, a leaching intensity of 1 L / min, and a leaching time of 1 day.

Claims

1. A physical simulation device for the catastrophic formation of unstable rock masses under alternating acid rain and dry / wet conditions, characterized in that: The system includes a leaching chamber, a solution preparation tank, a model platform, an acid rain circulating leaching system, and a real-time monitoring system. It uses 3D scanning and 3D printing technology to print the unstable rock mass model components at a proportional scale. The printed unstable rock mass model components are then bonded and assembled using a muddy cementitious material, mainly composed of natural weathering products from the structural surfaces of the unstable rock mass, to form the unstable rock mass model. During the leaching process, the acid rain circulating leaching system is used to adjust the leaching intensity to simulate natural conditions. The etching chamber consists of a chamber body and a cover. A removable cover is installed at the open end of the chamber body. The cover is connected to an external solution preparation tank via an acid rain circulating etching system. The solution preparation tank is equipped with an ion meter for monitoring NO3 in the solution. - Ions, SO4 2- The concentration of ions and the pH value of the solution are monitored in real time throughout the leaching chamber; the model platform is placed in the middle of the cavity of the leaching chamber. The real-time monitoring system mainly consists of a video monitoring system, an acoustic emission monitoring system, a miniature rebar gauge, a miniature crack gauge, and an ion meter. The cameras of the video monitoring system are installed on the frontal, lateral, and isometric views of the unstable rock mass model. The acoustic emission sensors in the acoustic emission monitoring system are distributed at the upper right, lower right, and locking sections of the unstable rock mass model. The rebar gauge is embedded inside the unstable rock mass model, spanning both sides of the main control structural surface. The miniature crack gauge is fixed to the upper end of the unstable rock mass model, spanning both sides of the main control structural surface. The acid rain circulating leaching system consists of two circulating water pumps connected to a leaching tank and a solution preparation tank via inlet pipes. One of the circulating water pumps is connected to a spray pipe fixed inside the leaching tank via a circulating leaching inlet valve on the leaching tank cover. The other circulating water pump is connected to the leaching tank and the solution preparation tank via a circulating leaching outlet valve on the leaching tank cover. The inside of the circulating leaching outlet valve on the leaching tank cover is connected to the solution level below the leaching tank via an inlet pipe, and the outside is connected to the solution level below the solution level in the solution preparation tank via an inlet pipe.

2. The physical simulation device for the catastrophic formation of unstable rock masses under alternating acid rain and dry / wet conditions as described in claim 1, characterized in that: The model platform is an integral loading device cast from a single piece of PAM board material.

3. The physical simulation device for the catastrophic formation of unstable rock masses under alternating acid rain and dry / wet conditions as described in claim 1, characterized in that: The spray pipe is mainly composed of an atomizing spray head and an infusion pipe.

4. The method of using the physical simulation device for the catastrophic formation of unstable rock masses under alternating acid rain and dry / wet conditions as described in claim 1, characterized in that, Includes the following steps: Step 1: Before the leaching test begins, the pre-embedded monitoring devices, namely micro steel bar gauges and micro crack gauges, are pre-installed on the unstable rock mass model. Then, muddy cement, mainly composed of natural weathering products at the structural surface of the unstable rock mass, is used as the locking section to bond and assemble the printed unstable rock mass model components. After the unstable rock mass model is assembled, the acoustic emission sensors are connected and fixed in the predetermined positions. Step 2: Place the prepared unstable rock mass model on the model platform, then place the model platform together with the unstable rock mass model inside the leaching box, and adjust the position of the unstable rock mass model so that the front and side of the unstable rock mass model are aligned with the monitoring cameras in the front and side view directions of the video monitoring system. Step 3: After the unstable rock mass model is placed, prepare the leaching solution in the preparation tank, monitor the solution using an ion meter, and adjust the NO3 content of the leaching solution. - Ion concentration, SO4 2- Once the ion concentration and solution pH value reach the target values ​​of the test plan, the ion meter is always on to record the changes in ion concentration of the leaching solution during the leaching process. Then, check the connection between the circulating water pump and the delivery pipe. The delivery pipe in the solution tank is below the liquid level in the solution tank. Then connect the circulating leaching inlet valve on the leaching tank cover to the spray pipe inside the leaching tank. At the same time, adjust the delivery pipe connected to the circulating leaching outlet valve inside the leaching tank so that the delivery pipe is at the bottom of the leaching tank. Step 4: Connect the power supply and turn on the circulating water pump connected to the circulating leaching inlet valve on the leaching chamber cover for pre-leaching. The liquid level in the leaching chamber should exceed the liquid delivery pipe connected to the circulating leaching outlet valve. Step 5: Turn on the monitoring camera and acoustic emission device, set the leaching time and leaching intensity, and turn on the circulating water pump connected to the circulating leaching outlet valve on the leaching chamber cover to perform circulating leaching. Step 6: After the predetermined leaching time is reached, turn off the circulating water pump connected to the circulating leaching inlet valve, and keep the circulating water pump connected to the circulating leaching outlet valve running to drain the accumulated solution in the leaching chamber; then remove the acoustic emission sensor, take out the unstable rock mass model, and let it stand to drain the residual leaching solution on the surface of the unstable rock mass model. After completion, copy the monitoring data from the video monitoring system camera, the acoustic emission monitoring system, the micro rebar gauge, the micro crack gauge, and the solution ion concentration change data recorded by the ion meter during the leaching process; remove the stage placed in the leaching chamber from the leaching chamber, and then pour out the remaining residual solution from the leaching chamber to clean it up. The leaching test is now complete. Step 7: Transfer the unstable rock mass model to a constant temperature drying oven for constant temperature drying treatment, and then repeat steps 1 to 6 above to conduct the next leaching test. Step 8: Repeat steps 1 to 7 above, subjecting the rock mass to acid rain erosion and drying N times until the rock mass is destroyed. Step 9, set the NO3 concentration for different leaching solutions - Ion concentration, SO4 2- Repeat steps 1 to 8 above, adjusting ion concentration, pH, leaching intensity, and leaching time.

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