A high-temperature and high-pressure rock triaxial and hydraulic fracturing test system and method for multi-block samples in separate compartments

Abstract

The application provides a high-temperature and high-pressure rock triaxial and hydraulic fracturing test system for multiple samples in separate compartments, which comprises a fracturing test compartment, the fracturing test compartment is arranged in a heat preservation and insulation compartment, a computer display, control and storage system is arranged outside the fracturing test compartment, and the computer display, control and storage system is controlled by a high-temperature heating and control system, an axial pressure loading and control system, a confining pressure loading and control system, a fracturing fluid injection pump and control system signal, the computer display, control and storage system is respectively connected with the high-temperature heating and control system, the axial pressure loading and control system, the confining pressure loading and control system, the fracturing fluid injection pump and control system and an acoustic emission monitoring system and an injection pressure monitoring system arranged in the fracturing test compartment, the fracturing test compartment is arranged in separate compartments, and the system comprises a high-temperature and high-pressure triaxial test method and a high-temperature and high-pressure hydraulic fracturing test method. The application has the advantages of improving test efficiency, shortening test period, simultaneously testing multiple core samples and forming intuitive comparative test.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of dry hot rock physical and mechanical research, and particularly relates to a high-temperature and high-pressure rock triaxial and hydraulic fracturing test system and method for loading multiple samples in separate compartments. BACKGROUND

[0002] Under the influence of atmospheric pollution and global warming caused by fossil fuels, countries around the world have begun to transform to a renewable and clean energy structure. Dry hot rock is usually buried thousands of meters deep, with a temperature greater than 200 DEG C, and contains abundant geothermal energy, and has the advantages of stable and continuous energy supply. The development of dry hot rock usually adopts an enhanced geothermal system, which injects high-pressure fluid into dry hot rock through a borehole, and expands the joint fissures of the rock mass through pressure to form a network of fissure seepage and heat exchange. The connectivity and formation of the fissure network have a huge impact on the exploitation of geothermal resources. Therefore, high-temperature and high-pressure rock triaxial and hydraulic fracturing tests are needed to better study the physical and mechanical properties of dry hot rock mass under high-temperature and high-pressure conditions and the behavior of the generated fissures under hydraulic fracturing stimulation.

[0003] At present, the hydraulic fracturing experiment can only test one sample, and because a high-temperature condition needs to be set, the heating and cooling time is relatively long, the test period is relatively long, and a contrast experiment of a stepped high temperature and high pressure cannot be directly formed. SUMMARY

[0004] The purpose of the present application is to provide a high-temperature and high-pressure rock triaxial and hydraulic fracturing test system and method for loading multiple samples in separate compartments, which can improve test efficiency, shorten test period, test multiple core samples at the same time, and form an intuitive contrast test.

[0005] In order to achieve the above purpose, the present application realizes the following technical scheme:

[0006] A high-temperature and high-pressure rock triaxial and hydraulic fracturing test system for loading multiple samples in separate compartments comprises a fracturing test compartment, which is placed in a heat preservation and insulation compartment, and is externally connected to a computer display, control and storage system and is controlled by a high-temperature heating and control system, an axial pressure loading and control system, a confining pressure loading and control system, a fracturing fluid injection pump and control system signal, the computer display, control and storage system is respectively connected in communication with the high-temperature heating and control system, the axial pressure loading and control system, the confining pressure loading and control system, the fracturing fluid injection pump and control system, and an acoustic emission monitoring system and an injection pressure monitoring system arranged in the fracturing test compartment, and the fracturing test compartment is divided into separate compartments.

[0007] Further, the fracturing test compartment is provided with a separate compartment frame, which comprises a frame fixing shaft and two vertically arranged separate compartment plates, each separate compartment plate is arranged with the fixing shaft as the center shaft and abuts against the inner wall of the fracturing test compartment.

[0008] Further, the axial pressure loading and control system is divided into four sub-chamber axial pressure loading and control systems according to the number of sub-chambers, respectively controlling the axial pressure loading of each single chamber; the confining pressure loading and control system is divided into four sub-chamber X-direction confining pressure loading and control systems and four sub-chamber Y-direction confining pressure loading and control systems according to the number of sub-chambers, respectively controlling the confining pressure loading of each single chamber in the X-direction and the Y-direction.

[0009] Further, a cold air machine is arranged at the opening and closing position of the heat insulation chamber to rapidly reduce the temperature of the fracturing test chamber.

[0010] A high-temperature and high-pressure rock triaxial test method for loading multiple samples in sub-chambers includes the following steps:

[0011] S1) Processing samples

[0012] The samples are processed into cuboids by a rock sample cutting machine to meet the size of the fracturing sub-chamber;

[0013] S2) Placing samples

[0014] Four processed samples a, b, c, and d are placed in the fracturing test single chamber in turn, and the two side surfaces of the samples are tightly attached to the sub-chamber plates;

[0015] S3) Fixing samples

[0016] The computer display, control and storage system controls the axial pressure loading and control system of each single chamber to push the axial steel plate to provide axial pressure, controls the single chamber X-direction confining pressure loading and control system to provide X-direction confining pressure, and controls the single chamber Y-direction confining pressure loading and control system to provide Y-direction confining pressure, thereby pre-applying a certain axial pressure and confining pressure to the samples for fixation;

[0017] S4) For sample a, heating is performed by the high-temperature heating and control system, and the computer display, control and storage system is used to display and control the heating to the required test temperature Ta of sample a;

[0018] S5) For sample a, the single chamber X-direction confining pressure loading and control system provides X-direction confining pressure, and the single chamber Y-direction confining pressure loading and control system provides Y-direction confining pressure, and the computer display, control and storage system is used to display and control the required test confining pressure Pa of sample a;

[0019] S6) For sample a, the single chamber axial pressure loading and control system pushes the axial steel plate to provide axial pressure until sample a is destroyed;

[0020] S7) If the test temperature does not need to be changed, repeat step S5) to apply confining pressure Pb to sample b, and then repeat step S6); if the test temperature needs to be changed, repeat step S4) to heat sample b to temperature Tb, then repeat step S5) to apply confining pressure Pb to sample b, and then repeat step S6);

[0021] Then, the above steps are repeated for samples c and d in turn.

[0022] S8) After the test is completed, the axial pressure loading and control system and the confining pressure loading and control system are unloaded to normal pressure, then the temperature insulation and heat insulation compartment is opened, the temperature of the test compartment is lowered to normal temperature by a cooling fan, and then the sample is taken out of the fracturing test compartment.

[0023] S9) All test parameters and data are collected and stored by the computer display, control and storage system, analyzed and processed using built-in software, and the test results required for high-temperature and high-pressure triaxial test are obtained.

[0024] Further, in step S7), four samples a, b, c and d can be assembled, four test temperatures Ta, Tb, Tc and Td are set from low to high, and four confining pressure conditions Pa, Pb, Pc and Pd are loaded to form a comparative test.

[0025] A high-temperature and high-pressure hydraulic fracturing test method for multiple samples in separate compartments, comprising the following steps:

[0026] S1) Processing samples

[0027] The samples are processed into cuboid shape by a rock sample cutting machine, which meets the size of the fracturing compartment, and a hole is drilled in the Z direction, i.e. the axial pressure application direction, until the middle of the sample, and a prefabricated fracturing steel pipe is embedded, which is tightly connected to the hole by sealing glue;

[0028] S2) Placing samples

[0029] Four processed samples a, b, c and d are placed in the fracturing test single compartment in turn, the two side surfaces of the samples are tightly attached to the compartment plates, and the fracturing fluid injection pump and control system are connected to the fracturing steel pipes of the samples;

[0030] S3) Fixing samples

[0031] The computer display, control and storage system controls the axial pressure loading and control system of each single compartment to provide axial pressure by pushing the axial steel plate, controls the X-direction confining pressure loading and control system to provide X-direction confining pressure, and controls the Y-direction confining pressure loading and control system to provide Y-direction confining pressure, thereby pre-applying a certain axial pressure and confining pressure to fix the samples;

[0032] S4) for sample a, heating by high temperature heating and control system, and displaying and controlling the required test temperature Ta of sample a by computer display, control and storage system;

[0033] S5) for sample a, providing X direction confining pressure by single-chamber X direction confining pressure loading and control system, providing Y direction confining pressure by single-chamber Y direction confining pressure loading and control system, and displaying and controlling the required test confining pressure Pa of sample a by computer display, control and storage system;

[0034] S6) for sample a, providing axial pressure by single-chamber axial pressure loading and control system, and displaying and controlling the required test axial pressure Pa' of sample a by computer display, control and storage system;

[0035] S7) injecting fracturing fluid into sample a at a speed Va by fracturing fluid injection pump and control system until sample a is damaged, monitoring and recording the injected pressure data by injection pressure monitoring system, and displaying and controlling the required injection speed Va and injection pressure Pa" of sample a by computer display, control and storage system;

[0036] S8) if the test temperature does not need to be changed, repeating steps S5), S6) to apply confining pressure Pb and axial pressure Pb' to sample b, and then repeating step S7) at injection speed Vb; if the test temperature needs to be changed, repeating step S4) to heat sample b to temperature Tb, and then repeating steps S5), S6) to apply confining pressure Pb and axial pressure Pb' to sample b, and then repeating step S7) at injection speed Vb;

[0037] The above steps are repeated for samples c and d in turn;

[0038] S9) after the test is completed, the axial pressure loading and control system and the confining pressure loading and control system are unloaded to remove the axial pressure and confining pressure to normal pressure, then the heat insulation and heat preservation chamber is opened, the temperature of the test chamber is lowered to normal temperature by a cooling fan, and then the fracturing test chamber is opened to take out the sample;

[0039] S10) all test parameters and data are stored by computer display, control and storage system, and analyzed and processed by built-in software to obtain the test results required by high temperature and high pressure hydraulic fracturing test.

[0040] Further, in step S8), four samples a, b, c and d can be assembled, four test temperatures Ta, Tb, Tc and Td are set from low to high, four confining pressure conditions Pa, Pb, Pc and Pd and four axial pressure conditions Pa', Pb', Pc' and Pd' are loaded, and four injection speeds Va, Vb, Vc and Vd are set to form a comparative test.

[0041] Compared with the prior art, the present application has the following advantages:

[0042] The application is a high-temperature and high-pressure rock triaxial and hydraulic fracturing test system and method for multiple samples in separate compartments, which improves test efficiency, shortens test period, can simultaneously test multiple core samples and can form intuitive comparative test. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 is a system structure schematic diagram of the application.

[0044] Figure 2 is a fracturing test compartment structure exploded schematic diagram of the application.

[0045] Figure 3 is a compartment grid structure schematic diagram of the application.

[0046] Figure 4 is a fracturing single-compartment structure schematic diagram of the application.

[0047] The drawing mark: 1, fracturing fluid injection pump and control system; 2, high-temperature heating and control system; 3, fracturing test compartment; 31, separate compartment axial pressure loading and control system; 311, single-compartment axial pressure loading and control system; 32, separate compartment X-direction confining pressure loading and control system; 321, single-compartment X-direction confining pressure loading and control system; 33, separate compartment grid; 331, grid fixed shaft; 332, separate compartment plate; 34, separate compartment Y-direction confining pressure loading and control system; 341, single-compartment Y-direction confining pressure loading and control system; 35, fracturing single-compartment; 4, axial pressure loading and control system; 5, confining pressure loading and control system; 6, injection pressure monitoring system; 7, acoustic emission monitoring system; 8, computer display, control and storage system; 9, heat preservation and insulation compartment; 10, cold air blower. DETAILED DESCRIPTION

[0048] The embodiments of the application are further described in detail below with reference to the drawings.

[0049] As Figure 1As shown, a high-temperature and high-pressure rock triaxial and hydraulic fracturing test system for multi-block samples in separate compartments includes a fracturing test compartment 3 placed in a heat preservation and insulation compartment 9, which can avoid heat loss, accelerate the heating speed, and ensure test safety through insulation. The fracturing test compartment 3 is externally connected to a computer display, control and storage system 8 and is controlled by a high-temperature heating and control system 2, an axial pressure loading and control system 4, a confining pressure loading and control system 5, a fracturing fluid injection pump and control system 1 signal. The computer display, control and storage system 8 is respectively connected in communication with the high-temperature heating and control system 2, the axial pressure loading and control system 4, the confining pressure loading and control system 5, the fracturing fluid injection pump and control system 1, and an acoustic emission monitoring system 7 and an injection pressure monitoring system 6 arranged in the fracturing test compartment 3, so as to change the temperature and pressure conditions in the fracturing test compartment 3, control the injection of fracturing fluid, monitor and record the injection pressure and acoustic emission events; the computer display, control and storage system 8 can display and store the changes of each parameter in real time, control the related systems to change the parameters, and process the test and monitoring data by using the built-in processing software. The heat preservation and insulation compartment 9 is provided with a cold air blower 10 at the opening and closing position, which can quickly reduce the temperature of the fracturing test compartment 3.

[0050] Specifically, the fracturing fluid injection pump and control system 1 is composed of a fracturing fluid storage tank, a fracturing fluid injection pump, an injection pump control system, and a liquid injection pipe. The fracturing fluid storage tank contains water and supercritical CO 2 and other fracturing fluids. One end of the liquid injection pipe is connected to the fracturing fluid storage tank, and the other end is provided with four injection ports and is respectively connected to the fracturing steel pipes of the samples in the fracturing single compartment 35. The injection flow rate can be controlled, and the rock sample can be fractured by injecting fracturing fluid into the rock sample. The high-temperature heating and control system 2 is composed of an electric heating wire and a heating control system. The electric heating wire is located at the position of the wall of the fracturing test compartment, and heat is provided by the electric heating wire to change and record the temperature in the fracturing test compartment 3. The axial pressure loading and control system 4 is composed of a servo hydraulic machine and an axial steel plate. The servo hydraulic machine is located at the bottom of the test fracturing compartment 3 and is a Z-direction axial force system, which is divided into four compartment loading modules and can provide different axial forces for the four compartments, respectively, to perform triaxial tests or provide the required axial force for hydraulic fracturing tests, and the axial force is recorded. The confining pressure loading and control system 5 is an X and Y direction confining pressure system composed of a servo hydraulic machine and X and Y direction steel plates. The servo hydraulic machine is located outside the fracturing test compartment 3 and is divided into four compartment loading modules, which can provide different confining pressures for the four compartments, respectively, to perform triaxial tests or provide the required confining pressure for hydraulic fracturing tests, and the confining pressure is recorded. The injection pressure monitoring system 6 is arranged with a pressure probe near the prefabricated fracturing steel pipe of the liquid injection pipe of the fracturing fluid injection pump and control system 1, which can monitor and record the injection pressure. The acoustic emission monitoring system 7 is arranged with an acoustic emission probe in the fracturing test compartment 3, which can monitor the acoustic waves generated by the deformation and failure of the sample throughout the process, locate the fracture, and reflect the process and severity of the fracture formation.

[0051] As Figure 2 , 3 , 4, the fracturing test bin 3 is divided into four bins, and the fracturing test bin 3 is provided with a bin frame 33, which includes a frame fixing shaft 331 and two vertically arranged bin plates 332. Each bin plate 332 is centered on the fixing shaft 331 and abuts the inner wall of the fracturing test bin 3, i.e., the fracturing test bin 3 is divided into four fracturing single bins 35.

[0052] The axial pressure loading and control system 4 is divided into four bin axial pressure loading and control systems 41 according to the number of bins, which respectively control the axial pressure loading of each fracturing single bin 35; the confining pressure loading and control system 5 is divided into four bin X-direction confining pressure loading and control systems 32 and four bin Y-direction confining pressure loading and control systems 34 according to the number of bins, which respectively control the confining pressure loading of each single bin in the X-direction and the Y-direction. The establishment of axial pressure and confining pressure is provided by a servo motor pushing a steel plate, which converts voltage signals into torque and speed to drive the control object, with very accurate position accuracy. During the process of pressurization and fracturing, the acoustic emission monitoring system 7 monitors the acoustic waves generated by the deformation and failure of the sample throughout the process, locates the fracture and reflects the process and severity of crack formation; the injection pressure monitoring system 6 monitors the change of injection pressure throughout the process. Embodiment

[0053] A high-temperature and high-pressure rock triaxial test method for loading multiple samples in separate bins, comprising the following steps:

[0054] S1) Processing the sample

[0055] The sample is processed into a cuboid shape by a rock sample cutting machine to meet the size of the fracturing bin;

[0056] S2) Placing the sample

[0057] Four processed samples a, b, c, and d are placed in the fracturing single bin 35 in turn, with the two side surfaces of the sample abutting the bin plate 332;

[0058] S3) Fixing the sample

[0059] The computer display, control and storage system 8 controls the single bin axial pressure loading and control system 311 to push the axial steel plate to provide axial pressure, controls the single bin X-direction confining pressure loading and control system 321 to provide X-direction confining pressure, and controls the single bin Y-direction confining pressure loading and control system 341 to provide Y-direction confining pressure, thereby pre-applying a certain axial pressure and confining pressure to the sample for fixation;

[0060] S4) For sample a, heating by high temperature heating and control system 2, and displaying and controlling the required test temperature Ta for sample a by computer display, control and storage system 8;

[0061] S5) For sample a, providing X-direction confining pressure by single-chamber X-direction confining pressure loading and control system 321, providing Y-direction confining pressure by single-chamber Y-direction confining pressure loading and control system 341, and displaying and controlling the required test confining pressure Pa for sample a by computer display, control and storage system 8;

[0062] S6) For sample a, pushing the axial steel plate by single-chamber axial pressure loading and control system 311 until the sample a is destroyed;

[0063] S7) If the test temperature does not need to be changed, repeating step S5) to apply confining pressure Pb to sample b, and then repeating step S6); if the test temperature needs to be changed, repeating step S4) to heat sample b to temperature Tb, then repeating step S5) to apply confining pressure Pb to sample b, and then repeating step S6);

[0064] The above steps are repeated in turn for samples c and d;

[0065] S8) After the test is completed, the axial pressure loading and control system 4 and the confining pressure loading and control system 5 are unloaded to atmospheric pressure, then the heat insulation chamber 9 is opened, the temperature of the fracturing test chamber 3 is lowered to room temperature by the air cooler 10, and then the fracturing test chamber 3 is opened to take out the sample;

[0066] S9) All test parameters and data are stored by computer display, control and storage system 8, analyzed and processed using built-in software, and the required test results of high temperature and high pressure triaxial test are obtained.

[0067] Further, in step S7), four samples a, b, c, and d can be assembled for the test, four test temperatures Ta, Tb, Tc, and Td are set from low to high, and four confining pressure conditions Pa, Pb, Pc, and Pd are loaded to form a comparative test. Embodiment

[0068] A high temperature and high pressure hydraulic fracturing test method for multi-piece samples with separate chamber loading, comprising the following steps:

[0069] S1) Processing the sample

[0070] The sample is processed into a cuboid shape by a rock sample cutting machine, which meets the size of the fracturing separate chamber, and a hole is drilled in the Z direction, i.e. the axial pressure application direction, to the middle of the sample, and a prefabricated fracturing steel pipe is embedded, which is tightly connected to the hole by sealing glue;

[0071] S2) Placing the sample

[0072] Four pieces of processed sample a, b, c, d are put into the single chamber 3 in turn, the two sides of the sample are tightly attached to the chamber plate 332, and the fracturing fluid injection pump and control system 1 is connected with the fracturing steel tube of the sample;

[0073] S3) Fix the sample

[0074] The computer display, control and storage system 8 controls the axial pressure loading and control system 311 to push the axial steel plate to provide axial pressure, controls the single chamber X-direction confining pressure loading and control system 321 to provide X-direction confining pressure, and controls the single chamber Y-direction confining pressure loading and control system 341 to provide Y-direction confining pressure, so as to pre-apply a certain axial pressure and confining pressure to the sample for fixation;

[0075] S4) For sample a, heating is performed by the high-temperature heating and control system 2, and the computer display, control and storage system 8 is used to display and control the heating to the required test temperature Ta of sample a;

[0076] S5) For sample a, the X-direction confining pressure is provided by the single chamber X-direction confining pressure loading and control system 321, the Y-direction confining pressure is provided by the single chamber Y-direction confining pressure loading and control system 341, and the computer display, control and storage system 8 is used to display and control the required test confining pressure Pa of sample a;

[0077] S6) For sample a, the axial pressure is provided by the single chamber axial pressure loading and control system 311, and the computer display, control and storage system 8 is used to display and control the required test axial pressure Pa' of sample a;

[0078] S7) The fracturing fluid injection pump and control system 1 injects the fracturing fluid into sample a at a speed Va until sample a is damaged, the injection pressure data is monitored and recorded by the injection pressure monitoring system 6, and the computer display, control and storage system 8 is used to display and control the required injection speed Va and injection pressure Pa" of sample a;

[0079] S8) If the test temperature does not need to be changed, steps S5) and S6) are repeated to apply confining pressure Pb and axial pressure Pb' to sample b, and then step S7) is repeated at injection speed Vb; if the test temperature needs to be changed, step S4) is repeated to heat sample b to temperature Tb, and then steps S5) and S6) are repeated to apply confining pressure Pb and axial pressure Pb' to sample b, and then step S7) is repeated at injection speed Vb;

[0080] The above steps are repeated in turn for samples c and d;

[0081] S9) After the test is completed, the axial pressure loading and control system 4 and the confining pressure loading and control system 5 are unloaded to normal pressure, and then the temperature insulation compartment 9 is opened, the temperature of the fracturing test compartment 3 is lowered to normal temperature by the air cooler 10, and then the fracturing test compartment 3 is opened to take out the sample;

[0082] S10) All test parameters and data are stored by the computer display, control and storage system 8, analyzed and processed by the built-in software, and the test results required by the high-temperature and high-pressure hydraulic fracturing test are obtained.

[0083] Further, in step S8), four kinds of samples a, b, c and d can be assembled, four test temperatures Ta, Tb, Tc and Td are set from low to high, four confining pressure conditions Pa, Pb, Pc and Pd and four axial pressure conditions Pa', Pb', Pc' and Pd' are loaded, and four injection speeds Va, Vb, Vc and Vd are set to form a comparative test.

[0084] The above is only a preferred embodiment of the present application, and it should be noted that those skilled in the art can make improvements and refinements without departing from the concept of the present application, and these improvements and refinements should also be considered within the scope of protection of the present application.

Claims

1. A high temperature and high pressure rock triaxial and hydraulic fracturing test system of multi-block samples in separate compartments, comprising a fracturing test compartment, characterized in that: The fracturing test chamber is placed in the heat preservation and insulation chamber, and is externally connected with a computer display, control and storage system, and is controlled by a high temperature heating and control system, an axial pressure loading and control system, a confining pressure loading and control system, a fracturing fluid injection pump and control system, the computer display, control and storage system is respectively connected with the high temperature heating and control system, the axial pressure loading and control system, the confining pressure loading and control system, the fracturing fluid injection pump and control system and an acoustic emission monitoring system and an injection pressure monitoring system arranged in the fracturing test chamber, and the fracturing test chamber is divided into chambers; The fracturing test chamber is provided with a chamber grid, which comprises a grid fixing shaft and two vertically arranged chamber plates, and each chamber plate is arranged around the fixing shaft as a center shaft and abuts against the inner wall of the fracturing test chamber; The axial pressure loading and control system is divided into four chamber axial pressure loading and control systems according to the number of chambers, and each chamber axial pressure loading and control system controls the axial pressure loading of each single chamber, and the confining pressure loading and control system is divided into four chamber X-direction confining pressure loading and control systems and four chamber Y-direction confining pressure loading and control systems according to the number of chambers, and each chamber X-direction confining pressure loading and control system and each chamber Y-direction confining pressure loading and control system controls the X-direction and Y-direction confining pressure loading of each single chamber.

2. The high temperature and high pressure rock triaxial and hydraulic fracturing test system of the multi-block sample with bin loading according to claim 1, characterized in that: A cold air machine is arranged at the opening and closing position of the heat preservation and insulation chamber, which can rapidly reduce the temperature of the fracturing test chamber.

3. The high-temperature high-pressure rock triaxial test method of the compartmental loading multi-block specimen high-temperature high-pressure rock triaxial and hydraulic fracturing test system according to claim 1, characterized in that The method comprises the following steps: S1) processing a sample The sample is processed into a cuboid shape by a rock sample cutting machine, so as to meet the size of the fracturing chamber; S2) placing the sample Four processed samples a, b, c and d are sequentially placed in the fracturing test chamber, and two side surfaces of the sample abut against the chamber plates; S3) fixing the sample The axial pressure loading and control system of each single chamber is controlled by the computer display, control and storage system to push the axial steel plate to provide axial pressure, the X-direction confining pressure loading and control system of each single chamber is controlled to provide X-direction confining pressure, and the Y-direction confining pressure loading and control system of each single chamber is controlled to provide Y-direction confining pressure, so as to preliminarily apply certain axial pressure and confining pressure to the sample for fixation; S4) for the sample a, heating is performed by the high temperature heating and control system, and the computer display, control and storage system is used to display and control the heating to the required test temperature Ta of the sample a; S5) for the sample a, the X-direction confining pressure loading and control system of the single chamber is used to provide X-direction confining pressure, and the Y-direction confining pressure loading and control system of the single chamber is used to provide Y-direction confining pressure, and the computer display, control and storage system is used to display and control the required test confining pressure Pa of the sample a; S6) for the sample a, the axial steel plate is pushed by the axial pressure loading and control system of the single chamber to provide axial pressure until the sample a is damaged; S7) if the test temperature does not need to be changed, step S5) is repeated, the confining pressure Pb is applied to the sample b, and then step S6) is repeated; if the test temperature needs to be changed, step S4) is repeated, the sample b is heated to the temperature Tb, then step S5) is repeated, the confining pressure Pb is applied to the sample b, and then step S6) is repeated; The above steps are sequentially repeated for the samples c and d. S8) After the test is completed, the axial pressure loading and control system and the confining pressure loading and control system are unloaded to normal pressure, and then the temperature insulation compartment is opened, the temperature of the test compartment is lowered to normal temperature by a cooling fan, and then the fracturing test compartment is opened to take out the sample; S9) All test parameters and data are stored by the computer display, control and storage system, analyzed and processed by the built-in software, and the test results required by the high-temperature and high-pressure triaxial test are obtained.

4. The high-temperature and high-pressure rock triaxial test method of the split-chamber loading multi-piece sample according to claim 3, characterized in that: In step S7), four kinds of samples a, b, c and d can be assembled, and four test temperatures Ta, Tb, Tc and Td are set from low to high, and four confining pressure conditions Pa, Pb, Pc and Pd are loaded to form a contrast test.

5. A high temperature and high pressure hydraulic fracturing test method of a high temperature and high pressure rock triaxial and hydraulic fracturing test system of a compartmentalized loading multi-block sample according to claim 1, characterized by Comprising the following steps: S1) Processing the sample The sample is processed into a cuboid shape by a rock sample cutting machine, which meets the size of the fracturing split chamber, and a hole is drilled in the middle of the sample along the Z direction, i.e., the axial pressure application direction, and a prefabricated fracturing steel pipe is embedded, and the steel pipe is tightly connected with the hole through sealing glue; S2) Placing the sample Four processed samples a, b, c and d are placed in the fracturing test single chamber in turn, the two side surfaces of the sample are tightly attached to the split chamber plate, and the fracturing fluid injection pump and control system is connected with the sample steel pipe; S3) Fixing the sample The axial steel plate is pushed to provide axial pressure by controlling the axial pressure loading and control system of each single chamber through the computer display, control and storage system, the X-direction confining pressure loading and control system is controlled to provide X-direction confining pressure, and the Y-direction confining pressure loading and control system is controlled to provide Y-direction confining pressure, so as to pre-apply a certain axial pressure and confining pressure to the sample for fixation; S4) For sample a, heating is performed by the high-temperature heating and control system, and the computer display, control and storage system is used to display and control the heating to the required test temperature Ta of sample a; S5) For sample a, the X-direction confining pressure is provided by the single chamber X-direction confining pressure loading and control system, the Y-direction confining pressure is provided by the single chamber Y-direction confining pressure loading and control system, and the computer display, control and storage system is used to display and control the required test confining pressure Pa of sample a; S6) For sample a, the axial pressure is provided by the single chamber axial pressure loading and control system, and the computer display, control and storage system is used to display and control the required test axial pressure Pa' of sample a; S7) The fracturing fluid is injected into sample a at a speed Va by the fracturing fluid injection pump and control system until sample a is destroyed, the pressure data of the injection is monitored and recorded by the injection pressure monitoring system, and the computer display, control and storage system is used to display and control the required injection speed Va and injection pressure Pa" of sample a; S8) If the test temperature does not need to be changed, steps S5) and S6) are repeated to apply confining pressure Pb and axial pressure Pb' to sample b, and then step S7) is repeated at injection speed Vb; if the test temperature needs to be changed, step S4) is repeated to heat sample b to temperature Tb, and then steps S5) and S6) are repeated to apply confining pressure Pb and axial pressure Pb' to sample b, and then step S7) is repeated at injection speed Vb; Then, the above steps are repeated for the samples c and d in turn; S9) After the test is completed, the axial pressure loading and control system and the confining pressure loading and control system are unloaded to normal pressure, and then the temperature insulation and heat insulation bin is opened, the temperature of the test bin is reduced to normal temperature by the air cooler, and then the fracturing test bin is opened to take out the sample; S10) All test parameters and data are stored by the computer display, control and storage system, and analyzed and processed by the built-in software to obtain the test results required by the high temperature and high pressure hydraulic fracturing test.

6. The method according to claim 5, wherein the method is characterized by: In step S8), four samples a, b, c and d can be assembled, four test temperatures Ta, Tb, Tc and Td are set from low to high, four confining pressure conditions Pa, Pb, Pc and Pd and four axial pressure conditions Pa', Pb', Pc' and Pd' are loaded, and four injection speeds Va, Vb, Vc and Vd are set to form a comparative test.

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