A test device and method for testing shear slip characteristics of faults in carbon storage sites

Abstract

The present invention relates to the technical field of carbon sequestration test, and in particular to a test device and method for testing the shear slip characteristics of faults in a carbon sequestration site, comprising an SC-CO2 supply system and a rock direct shear test system, wherein the rock direct shear test system comprises a rock press, a direct shear chamber, a rock sample, a normal pressure servo control and stress displacement recording mechanism, a tangential pressure servo control and stress displacement recording mechanism, an injection pipe, a control mechanism and an acoustic emission probe, wherein normal and tangential stresses are applied to the rock sample through the normal pressure servo control and stress displacement recording mechanism and the tangential pressure servo control and stress displacement recording mechanism, the gas in the direct shear chamber is replaced with SC-CO2 through the SC-CO2 supply system, and the temperature in the direct shear chamber is ensured through the control mechanism, so as to simulate the shear slip of a rock structural surface under the influence of SC-CO2, and study the reduction of effective stress of the structural surface, the reduction of friction coefficient and the shear slip characteristics.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon storage test, and in particular to a test device and method for testing the shear slip characteristics of a fault in a carbon storage site. Background Art

[0002] Carbon sequestration is a geological response and countermeasure to global climate change. Injecting huge volumes of supercritical carbon dioxide (SC-CO2) and sealing them in deep underground reservoirs can help achieve the goal of carbon neutrality. The mechanism of carbon sequestration-induced earthquakes is that the original faults in the storage area are in a stress equilibrium state. After the injection of SC-CO2 fluid, the fluid pressure offsets part of the confining pressure and normal pressure, the pore water pressure on the structural surface increases, and the effective stress decreases. At the same time, the adsorption of SC-CO2 on rocks reduces the friction coefficient between the structural surfaces of the fault, ultimately causing the fault to slip.

[0003] At present, there is no test device case for evaluating the shear-slip characteristics of faults under the influence of SC-CO2, and it is impossible to quantitatively analyze the reduction of effective stress, friction coefficient reduction and shear-slip characteristics of structural surfaces under the influence of SC-CO2. Summary of the invention

[0004] The purpose of the present invention is to provide a test device and method for testing the shear slip characteristics of faults in carbon storage sites, aiming to solve the problem of being unable to quantitatively analyze the reduction of effective stress, friction coefficient reduction and shear slip characteristics of structural surfaces under the influence of SC-CO2.

[0005] To achieve the above-mentioned object, in a first aspect, the present invention provides a test device for testing the shear slip characteristics of faults in carbon storage sites, comprising a SC-CO2 supply system and a rock direct shear test system;

[0006] The rock direct shear test system includes a rock press, a direct shear chamber, a rock sample, a normal pressure servo control and stress displacement recording mechanism, a tangential pressure servo control and stress displacement recording mechanism, an injection pipe, a control mechanism and an acoustic emission probe. The direct shear chamber is arranged on one side of the rock press, and the rock sample is arranged in the direct shear chamber. The normal pressure servo control and stress displacement recording mechanism is arranged on one side of the rock press and is connected to the rock sample and passes through the top of the direct shear chamber. The tangential pressure servo control and stress displacement recording mechanism is arranged on one side of the rock press and is connected to the rock sample and passes through the side wall of the direct shear chamber. The injection pipe is arranged between the SC-CO2 supply system and the direct shear chamber, the control mechanism is arranged on one side of the direct shear chamber, and the acoustic emission probe is arranged on one side of the rock sample.

[0007] Wherein, the rock sample includes a lower rock block and an upper rock block, the lower rock block is fixedly arranged in the direct shear chamber, the upper rock block is arranged on one side of the lower rock block, and is connected to the normal pressure servo control and stress displacement recording mechanism and the tangential pressure servo control and stress displacement recording mechanism, and is located in the direct shear chamber, the lower rock block has a lower structural surface, and the upper rock block has an upper structural surface, the lower structural surface is located on the side of the lower rock block close to the upper rock block, and the upper structural surface is located on the side of the upper rock block close to the lower structural surface.

[0008] Wherein, the control mechanism includes an exhaust pipe, a second pressure regulating valve, a second solenoid valve, a heating module, a temperature and pressure real-time monitoring module and two sealing sleeves, the exhaust pipe is arranged on the side of the direct shear chamber away from the injection pipe, the second pressure regulating valve is arranged on the side of the injection pipe, the second solenoid valve is arranged on the side of the exhaust pipe, the heating module is arranged around the direct shear chamber, the temperature and pressure real-time monitoring module is arranged on one side of the direct shear chamber, the sealing sleeve is arranged between the direct shear chamber and the normal pressure servo control and stress displacement recording mechanism, and the other sealing sleeve is arranged between the direct shear chamber and the tangential pressure servo control and stress displacement recording mechanism.

[0009] Wherein, the SC-CO2 supply system includes a liquid carbon dioxide cylinder, a connecting pipe, a booster pump, a pressure autoclave, a heating assembly, a first pressure regulating valve, a first solenoid valve and a pressure sensor. The connecting pipe is fixedly connected to the liquid carbon dioxide cylinder and is located on one side of the liquid carbon dioxide cylinder. The booster pump is fixedly connected to the connecting pipe and is located on a side away from the liquid carbon dioxide cylinder. The pressure autoclave is arranged between the booster pump and the injection pipe. The heating assembly is arranged on the outer side wall of the pressure autoclave. The first pressure regulating valve is arranged on one side of the connecting pipe. The first solenoid valve is arranged on one side of the injection pipe. The pressure sensor is arranged on one side of the pressure autoclave.

[0010] Wherein, the heating assembly includes a heating belt and a temperature controller, the heating belt is fixedly connected to the autoclave and is located on the outer side wall of the autoclave, and the temperature controller is arranged on one side of the heating belt.

[0011] Wherein, the SC-CO2 supply system also includes a thermal insulation cotton cover, which is fixedly connected to the injection pipe and is located around the injection pipe.

[0012] In a second aspect, the present invention provides a test method for testing the shear slip characteristics of a fault in a carbon storage site, comprising the following steps:

[0013] Applying normal stress and tangential stress to the rock sample in the direct shear chamber through the normal pressure servo control and stress displacement recording mechanism and the tangential pressure servo control and stress displacement recording mechanism respectively until the rock sample is in a stress equilibrium state;

[0014] Use SC-CO2 to replace the gas in the direct shear chamber through the SC-CO2 supply system, and the gas is discharged through the exhaust pipe;

[0015] The pressure and temperature of the SC-CO2 in the direct shear chamber are adjusted to the preset values ​​through the control mechanism;

[0016] The acoustic emission signal is recorded by an acoustic emission probe, the normal stress and normal displacement change process is recorded by a normal pressure servo control and a stress displacement recording mechanism, and the tangential stress and tangential displacement change process is recorded by a tangential pressure servo control and a stress displacement recording mechanism;

[0017] The preset values ​​of pressure and temperature, acoustic emission signals, normal stress, normal displacement change process, tangential stress, and tangential displacement change process are sorted and analyzed to obtain the test results;

[0018] After the SC-CO2 is exhausted, the direct shear chamber is opened to observe and analyze the shear friction deformation and failure characteristics of the rock block structural surface.

[0019] The present invention discloses a test device and method for testing the shear-slip characteristics of faults in a carbon storage site. The normal stress and the tangential stress are applied to the rock sample by the normal pressure servo control and stress-displacement recording mechanism and the tangential pressure servo control and stress-displacement recording mechanism, so that the rock sample simulates a rock fault. The gas in the direct shear chamber is replaced with SC-CO2 by the SC-CO2 supply system, and the temperature and pressure in the direct shear chamber are ensured by the control mechanism. The shear slip of the rock sample under the influence of SC-CO2 is simulated, and the effective stress reduction, friction coefficient reduction and shear slip characteristics are studied, so as to solve the problem that it is impossible to quantitatively analyze the effective stress reduction, friction coefficient reduction and shear slip characteristics of the structural surface under the influence of SC-CO2. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a cross-sectional view of a test device for testing the shear slip characteristics of a fault in a carbon storage site provided by the present invention.

[0022] Figure 2 It is a cross-sectional view of a control mechanism, an acoustic emission probe, a normal pressure servo control and stress-displacement recording mechanism, a tangential pressure servo control and stress-displacement recording mechanism, and a rock sample.

[0023] Figure 3 It is a radial cross-sectional view of the injection tube and the thermal insulation cotton sleeve.

[0024] Figure 4 It is a schematic diagram of a structure in which an upper rock block and the lower rock block are in contact.

[0025] Figure 5 It is a flow chart of an experimental method for testing the shear slip characteristics of a fault in a carbon storage site provided by the present invention.

[0026] 1-SC-CO2 supply system, 2-rock direct shear test system;

[0027] 101-liquid carbon dioxide cylinder, 102-first pressure regulating valve, 103-boosting pump, 104-pressure kettle, 105-heating belt, 106-pressure sensor, 107-temperature controller, 108-first solenoid valve, 109-insulation cotton cover, 110-heating component, 111-connecting pipe;

[0028] 201-upper rock block, 202-lower rock block, 204-direct shear chamber, 205-normal pressure servo control and stress-displacement recording mechanism, 206-tangential pressure servo control and stress-displacement recording mechanism, 207-rock press, 208-injection pipe, 209-exhaust pipe, 210-second solenoid valve, 211-heating module, 212-temperature and pressure real-time monitoring module, 213-acoustic emission probe, 214-sealing sleeve, 215-second pressure regulating valve, 216-control mechanism, 217-rock sample, 2031-upper structural surface, 2032-lower structural surface. DETAILED DESCRIPTION

[0029] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0030] See also Figures 1 to 4 In a first aspect, the present invention provides a test device for testing the shear slip characteristics of a fault in a carbon storage site, comprising a SC-CO2 supply system 1 and a rock direct shear test system 2;

[0031] The rock direct shear test system 2 includes a rock press 207, a direct shear chamber 204, a rock sample 217, a normal pressure servo control and stress displacement recording mechanism 205, a tangential pressure servo control and stress displacement recording mechanism 206, an injection pipe 208, a control mechanism 216 and an acoustic emission probe 213. The direct shear chamber 204 is arranged on one side of the rock press 207, the rock sample 217 is arranged in the direct shear chamber 204, the normal pressure servo control and stress displacement recording mechanism 205 is arranged on the rock press 207, and the rock sample 217 is arranged in the direct shear chamber 204. on one side of the direct shear chamber 204, and is connected to the rock sample 217, and passes through the top of the direct shear chamber 204; the tangential pressure servo control and stress displacement recording mechanism 206 is arranged on one side of the rock press 207, and is connected to the rock sample 217, and passes through the side wall of the direct shear chamber 204; the injection pipe 208 is arranged between the SC-CO2 supply system 1 and the direct shear chamber 204; the control mechanism 216 is arranged on one side of the direct shear chamber 204; and the acoustic emission probe 213 is arranged on one side of the rock sample 217.

[0032] In this embodiment, the normal stress and tangential stress are applied to the rock sample 217 by the normal pressure servo control and stress displacement recording mechanism 205 and the tangential pressure servo control and stress displacement recording mechanism 206, so that the rock sample 217 simulates a rock fault, and the gas in the direct shear chamber 204 is replaced with SC-CO2 by the SC-CO2 supply system 1, and the pressure and temperature of the SC-CO2 in the direct shear chamber 204 are adjusted to preset values ​​by the control mechanism 216, so as to simulate the effective stress of the rock sample 217 in the SC-CO2. The force reduction and friction coefficient reduction characteristics are measured by recording the acoustic emission signal through the acoustic emission probe 213, recording the normal stress change process through the normal pressure servo control and stress displacement recording mechanism 205, and recording the tangential stress change process through the tangential pressure servo control and stress displacement recording mechanism 206. The preset values ​​of pressure and temperature, the acoustic emission signal, the normal stress change process and the tangential stress change process are sorted out and analyzed to obtain the test results, thereby solving the problem that it is impossible to quantitatively analyze the effective stress reduction, friction coefficient reduction and shear slip characteristics of the structural surface under the influence of SC-CO2.

[0033] Further, the rock sample 217 includes a lower rock block 202 and an upper rock block 201, the lower rock block 202 is fixedly arranged in the direct shear chamber 204, the upper rock block 201 is arranged on one side of the lower rock block 202, and is connected to the normal pressure servo control and stress displacement recording mechanism 205 and the tangential pressure servo control and stress displacement recording mechanism 206, and is located in the direct shear chamber 204, the lower rock block 202 has a lower structural surface 2032, the upper rock block 201 has an upper structural surface 2031, the lower structural surface 2032 is located on the side of the lower rock block 202 close to the upper rock block 201, and the upper structural surface 2031 is located on the side of the upper rock block 201 close to the lower structural surface 2032; the control mechanism 216 includes an exhaust pipe 209 , a second pressure regulating valve 215, a second solenoid valve 210, a heating module 211, a temperature and pressure real-time monitoring module 212 and two sealing sleeves 214, the exhaust pipe 209 is arranged on the side of the direct shear chamber 204 away from the injection pipe 208, the second pressure regulating valve 215 is arranged on the side of the injection pipe 208, the second solenoid valve 210 is arranged on the side of the exhaust pipe 209, the heating module 211 is arranged around the direct shear chamber 204, the temperature and pressure real-time monitoring module 212 is arranged on one side of the direct shear chamber 204, the sealing sleeve 214 is arranged between the direct shear chamber 204 and the normal pressure servo control and stress displacement recording mechanism 205, and the other sealing sleeve 214 is arranged between the direct shear chamber 204 and the tangential pressure servo control and stress displacement recording mechanism 206.

[0034] In this embodiment, the second pressure regulating valve 215 is located at the end of the injection pipe 208, the processing dimensions of the upper rock block 201 and the lower rock block 202 can be determined according to actual needs, the upper structural surface 2031 of the upper rock block 201 and the lower structural surface 2032 of the lower rock block 202 can be processed to different roughnesses according to needs, butter is applied on the contact surface between the upper rock block 201 and the normal pressure servo control and stress displacement recording mechanism 205 and the tangential pressure servo control and stress displacement recording mechanism 206, and the lower rock block 202 is provided with a pressure regulating valve 215. The contact surface between the rock block 202 and the direct shear chamber 204 is coated with butter to reduce the friction between the rock sample 217 and the press. The direct shear chamber 204 is provided with through holes for connecting the normal pressure servo control and stress displacement recording mechanism 205 and the tangential pressure servo control and stress displacement recording mechanism 206 with the upper rock block 201. The cross-sectional dimensions of the normal pressure servo control and stress displacement recording mechanism 205 and the tangential pressure servo control and stress displacement recording mechanism 206 are designed to be gradually varied, which can ensure that the normal and tangential stresses are applied in the process. The good airtightness of the direct shear chamber 204, the sealing sleeve 214 located between the direct shear chamber 204 and the normal pressure servo control and stress displacement recording mechanism 205, and the sealing sleeve 214 located between the direct shear chamber 204 and the tangential pressure servo control and stress displacement recording mechanism 206 further increase the airtightness of the direct shear chamber 204. The sealing sleeve 214 is a rubber sleeve. When the SC-CO2 supply system 1 injects SC-CO2 into the direct shear chamber 204, the gas in the direct shear chamber 204 is discharged from the exhaust pipe 209. After the gas is discharged, the temperature and pressure real-time monitoring module 212 monitors the pressure of SC-CO2 in the direct shear chamber 204. When the pressure reaches a preset value, the second solenoid valve 210 is closed. The pressure in the direct shear chamber 204 can be adjusted by the second pressure regulating valve 215. After the pressure adjustment is completed, the temperature and pressure real-time monitoring module 212 monitors the temperature in the direct shear chamber 204. When the temperature is lower than the preset value, the temperature in the direct shear chamber 204 is heated by the heating module 211 until the temperature in the direct shear chamber 204 reaches the preset value.

[0035] Furthermore, the SC-CO2 supply system 1 includes a liquid carbon dioxide cylinder 101, a connecting pipe 111, a booster pump 103, a pressure cooker 104, a heating component 110, a first pressure regulating valve 102, a first solenoid valve 108 and a pressure sensor 106, wherein the connecting pipe 111 is fixedly connected to the liquid carbon dioxide cylinder 101 and is located on one side of the liquid carbon dioxide cylinder 101, the booster pump 103 is fixedly connected to the connecting pipe 111 and is located on a side away from the liquid carbon dioxide cylinder 101, the pressure cooker 104 is arranged between the booster pump 103 and the injection pipe 208, and the heating component 110 is arranged on the pressure cooker 104 outer wall, the first pressure regulating valve 102 is arranged on one side of the connecting pipe 111, the first solenoid valve 108 is arranged on one side of the injection pipe 208, and the pressure sensor 106 is arranged on one side of the autoclave 104; the heating component 110 includes a heating belt 105 and a temperature controller 107, the heating belt 105 is fixedly connected to the autoclave 104 and is located on the outer wall of the autoclave 104, and the temperature controller 107 is arranged on one side of the heating belt 105; the SC-CO2 supply system 1 also includes a thermal insulation cotton cover 109, the thermal insulation cotton cover 109 is fixedly connected to the injection pipe 208 and is located around the injection pipe 208.

[0036] In this embodiment, when SC-CO2 is injected into the direct shear chamber 204, the first solenoid valve 108 on the connecting pipe 111 is opened, and the liquid carbon dioxide in the liquid carbon dioxide cylinder 101 flows into the autoclave 104 through the connecting pipe 111 and the booster pump 103. The pressure of the liquid carbon dioxide in the autoclave 104 is monitored by the pressure sensor 106, and the booster pump 103 is started. The booster pump 103 applies pressure (greater than 7.38MPa) to the autoclave 104. The pressure of the liquid carbon dioxide in the autoclave 104 can be further adjusted by the first pressure regulating valve 102 until the pressure of the liquid carbon dioxide in the autoclave 104 reaches the initial pressure of the test. At the same time, the booster pump 103 is started. The heating belt 105 of the heating component 110 heats the liquid carbon dioxide in the autoclave 104, and the temperature of the liquid carbon dioxide is monitored by the temperature controller 107 until the temperature of the liquid carbon dioxide reaches a preset temperature. At this time, the liquid carbon dioxide in the autoclave 104 is converted into SC-CO2. At this time, the first solenoid valve 108 on the injection pipe 208 is opened, and SC-CO2 flows into the direct shear chamber 204 through the injection pipe 208. The thermal insulation cotton cover 109 around the injection pipe 208 can prevent the SC-CO2 from causing temperature loss when flowing in the injection pipe 208, until the SC-CO2 discharges all the gas in the direct shear chamber 204, and the first solenoid valve 108 is closed.

[0037] See also Figure 5 In a second aspect, the present invention provides a test method for testing the shear slip characteristics of a fault in a carbon storage site, comprising the following steps:

[0038] S101: applying normal stress and tangential stress to the rock sample 217 in the direct shear chamber 204 through the normal pressure servo control and stress displacement recording mechanism 205 and the tangential pressure servo control and stress displacement recording mechanism 206, respectively, until the rock sample 217 is in a preset ultimate stress equilibrium state;

[0039] Specifically, the processing dimensions of the upper rock block 201 and the lower rock block 202 can be determined according to actual needs, the upper structural surface 2031 of the upper rock block 201 and the lower structural surface 2032 of the lower rock block 202 can be processed to different roughnesses according to needs, butter is applied on the contact surface between the upper rock block 201 and the normal pressure servo control and stress displacement recording mechanism 205 and the tangential pressure servo control and stress displacement recording mechanism 206, and butter is applied on the contact surface between the lower rock block 202 and the direct shear chamber 204 to reduce the friction between the rock sample 217 and the press, after the upper rock block 201 and the lower rock block 202 are placed in the direct shear chamber 204, normal stress and tangential stress are applied to make the rock sample 217 in a state of ultimate stress equilibrium, and then the control mechanism 216 heats the temperature in the direct shear chamber 204 to a preset value in advance.

[0040] S102 uses SC-CO2 to replace the gas in the direct shear chamber 204 through the SC-CO2 supply system 1, and the gas is discharged through the exhaust pipe 209;

[0041] Specifically, the process of injecting SC-CO2 into the direct shear chamber 204 is as follows: open the first solenoid valve 108 on the connecting pipe 111, and the liquid carbon dioxide in the liquid carbon dioxide cylinder 101 flows into the autoclave 104 through the connecting pipe 111 and the booster pump 103; close the first solenoid valve 108 and start the booster pump 103, the booster pump 103 applies pressure (greater than 7.38MPa) to the autoclave 104, control the booster valve to make the liquid carbon dioxide in the autoclave 104 reach the initial pressure of the test, start the heating belt 105 of the heating component 110 in advance, so that the heating belt 105 heats the liquid carbon dioxide in the autoclave 104, and monitor the temperature of the liquid carbon dioxide in real time through the temperature controller 107 and the pressure sensor 106 monitors the pressure of the autoclave in real time. The gas pressure in the pressure cooker 104 is reduced until the temperature of the liquid carbon dioxide reaches the preset temperature and the pressure reaches the preset pressure. At this time, the liquid carbon dioxide in the pressure cooker 104 is converted into SC-CO2, and the first solenoid valve 108 on the injection pipe 208 is opened. SC-CO2 flows into the direct shear chamber 204 through the injection pipe 208. The thermal insulation cotton cover 109 around the injection pipe 208 can prevent the temperature loss caused by the flow of SC-CO2 in the injection pipe 208. The second pressure regulating valve 215 and the second solenoid valve 210 are opened until SC-CO2 discharges all the gas in the direct shear chamber 204 (by observing the gas condensation at the second solenoid valve 210, it is judged whether the original air in the direct shear chamber 204 is exhausted). After the air in the direct shear chamber 204 is exhausted, the second solenoid valve 210 is closed.

[0042] S103 adjusts the pressure and temperature of the SC-CO2 in the direct shear chamber 204 to preset values ​​through the control mechanism 216;

[0043] Specifically, the flow rate of SC-CO2 is controlled by the second pressure regulating valve 215 so that the pressure in the direct shear chamber 204 reaches a preset pressure, and the temperature and pressure real-time monitoring module 212 of the control mechanism 216 is used to monitor the pressure of SC-CO2 in the direct shear chamber 204. When the pressure reaches the preset value, the second pressure regulating valve 215 and the first solenoid valve 108 are closed, and the temperature in the direct shear chamber 204 is preheated by the heating module 211. The temperature and pressure real-time monitoring module 212 monitors the temperature and pressure in the direct shear chamber 204, and performs secondary adjustment on the temperature in the direct shear chamber 204 until the temperature in the direct shear chamber 204 reaches the accurate preset value, thereby avoiding temperature loss of SC-CO2 when it flows into the direct shear chamber 204.

[0044] S104 records the acoustic emission signal through the acoustic emission probe 213, records the normal stress and normal displacement change process through the normal pressure servo control and stress displacement recording mechanism 205, and records the tangential stress and tangential displacement change process through the tangential pressure servo control and stress displacement recording mechanism 206;

[0045] S105 sorts out and analyzes the preset values ​​of pressure and temperature, the acoustic emission signal, the normal stress, the normal displacement change process, and the tangential stress, the tangential displacement change process to obtain the test results;

[0046] S106 After the SC-CO2 is exhausted, the direct shear chamber 204 is opened to observe and analyze the shear friction deformation and failure characteristics of the rock block structural surface.

[0047] The present invention provides an experimental method for testing the shear-slip characteristics of faults in carbon storage sites, which can be used to quantitatively analyze and describe the reduction in effective stress, friction coefficient reduction and shear-slip characteristics of structural surfaces under the influence of SC-CO2. The critical storage pressure of fault slip induced by SC-CO2 fluid injection can also be tested by experimental means, which is conducive to the research and development of relevant experimental instruments for the study of shear-slip characteristics of faults in carbon storage sites.

[0048] What is disclosed above is only a preferred embodiment of the test device and method for testing the shear slip characteristics of faults in carbon storage sites of the present invention. Of course, this cannot be used to limit the scope of rights of the present invention. Ordinary technicians in this field can understand that all or part of the processes of the above embodiments and equivalent changes made according to the claims of the present invention are still within the scope of the invention.

Claims

1. A test method for testing the shear slip characteristics of a fault at a carbon storage site, applied to a test device for testing the shear slip characteristics of a fault at a carbon storage site, It is characterized in that The following steps are involved: Applying normal stress and tangential stress to the rock sample in the direct shear chamber through the normal pressure servo control and stress displacement recording mechanism and the tangential pressure servo control and stress displacement recording mechanism respectively until the rock sample is in a stress equilibrium state; By SC-CO 2 Supply system using SC-CO 2 Replace the gas in the direct shear chamber and discharge the gas through the exhaust pipe; The SC-CO in the direct shear chamber is controlled by the control mechanism. 2 The pressure and temperature are adjusted to the preset values; The acoustic emission signal is recorded by an acoustic emission probe, the normal stress and normal displacement change process is recorded by a normal pressure servo control and a stress displacement recording mechanism, and the tangential stress and tangential displacement change process is recorded by a tangential pressure servo control and a stress displacement recording mechanism; The preset values ​​of pressure and temperature, acoustic emission signals, normal stress, normal displacement change process, tangential stress, and tangential displacement change process are sorted and analyzed to obtain the test results; SC-CO 2 After draining, open the direct shear chamber to observe and analyze the shear friction deformation and failure characteristics of the rock structure surface; The experimental device for testing the shear slip characteristics of the fault in the carbon storage site includes SC-CO 2 Supply system and rock direct shear test system; The rock direct shear test system comprises a rock press, a direct shear chamber, a rock sample, a normal pressure servo control and stress displacement recording mechanism, a tangential pressure servo control and stress displacement recording mechanism, an injection pipe, a control mechanism and an acoustic emission probe. The direct shear chamber is arranged on one side of the rock press, the rock sample is arranged in the direct shear chamber, the normal pressure servo control and stress displacement recording mechanism is arranged on one side of the rock press, and is connected to the rock sample and passes through the top of the direct shear chamber, the tangential pressure servo control and stress displacement recording mechanism is arranged on one side of the rock press, and is connected to the rock sample and passes through the side wall of the direct shear chamber, and the injection pipe is arranged on the SC-CO 2 Between the supply system and the direct shear chamber, the control mechanism is arranged on one side of the direct shear chamber, and the acoustic emission probe is arranged on one side of the rock sample.

2. The test method for testing the shear slip characteristics of a fault at a carbon storage site according to claim 1, It is characterized in that The rock sample includes a lower rock block and an upper rock block, the lower rock block is fixedly arranged in the direct shear chamber, the upper rock block is arranged on one side of the lower rock block, and is connected to the normal pressure servo control and stress displacement recording mechanism and the tangential pressure servo control and stress displacement recording mechanism, and is located in the direct shear chamber, the lower rock block has a lower structural surface, and the upper rock block has an upper structural surface, the lower structural surface is located on the side of the lower rock block close to the upper rock block, and the upper structural surface is located on the side of the upper rock block close to the lower structural surface.

3. The test method for testing the shear slip characteristics of a fault at a carbon storage site according to claim 2, It is characterized in that The control mechanism includes an exhaust pipe, a second pressure regulating valve, a second solenoid valve, a heating module, a temperature and pressure real-time monitoring module and two sealing sleeves. The exhaust pipe is arranged on the side of the direct shear chamber away from the injection pipe, the second pressure regulating valve is arranged on the side of the injection pipe, the second solenoid valve is arranged on the side of the exhaust pipe, the heating module is arranged around the direct shear chamber, the temperature and pressure real-time monitoring module is arranged on one side of the direct shear chamber, the sealing sleeve is arranged between the direct shear chamber and the normal pressure servo control and stress displacement recording mechanism, and the other sealing sleeve is arranged between the direct shear chamber and the tangential pressure servo control and stress displacement recording mechanism.

4. The test method for testing the shear slip characteristics of a fault at a carbon storage site according to claim 3, It is characterized in that The SC-CO 2 The supply system includes a liquid carbon dioxide cylinder, a connecting pipe, a booster pump, a pressure autoclave, a heating assembly, a first pressure regulating valve, a first solenoid valve and a pressure sensor. The connecting pipe is fixedly connected to the liquid carbon dioxide cylinder and is located on one side of the liquid carbon dioxide cylinder. The booster pump is fixedly connected to the connecting pipe and is located on a side away from the liquid carbon dioxide cylinder. The pressure autoclave is arranged between the booster pump and the injection pipe. The heating assembly is arranged on the outer side wall of the pressure autoclave. The first pressure regulating valve is arranged on one side of the connecting pipe. The first solenoid valve is arranged on one side of the injection pipe. The pressure sensor is arranged on one side of the pressure autoclave.

5. The test method for testing the shear slip characteristics of a fault at a carbon storage site according to claim 4, It is characterized in that The heating assembly comprises a heating belt and a temperature controller. The heating belt is fixedly connected to the autoclave and is located on the outer side wall of the autoclave. The temperature controller is arranged on one side of the heating belt.

6. The test method for testing the shear slip characteristics of a fault at a carbon storage site according to claim 5, It is characterized in that The SC-CO 2 The supply system also includes a heat-insulating cotton sleeve, which is fixedly connected to the injection pipe and is located around the injection pipe.

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