High-temperature and high-pressure rock hollow cylinder torsional shear physical multi-parameter measurement method

Abstract

The invention discloses a high-temperature and high-pressure rock hollow cylinder torsional shear physical multi-parameter measurement method, and relates to the technical field of rock mass mechanical tests. The method comprises the following steps: step 1, mounting a hollow rock sample in a measuring device; step 2, providing torque for the hollow rock sample; 3, starting a temperature control system, and heating the measuring device by using a temperature control outer lining; 4, during acoustic emission test, completing acoustic emission test related tests in combination with the temperature coupling torsional shear test; 5, completing ultrasonic test related tests; step 6, obtaining changes of resistivity under different environment conditions; step 7, simulating compressed air energy storage tests in different environments with a temperature coupling torsional shear test; and 8, completing multi-parameter measurement. The temperature control system, the ultrasonic testing system, the acoustic emission testing system and the resistivity testing system are freely combined and selected in a narrow reaction space according to test requirements.

Description

Technical Field

[0001] This invention relates to the field of rock mechanics testing technology, and more specifically, to a multi-parameter physical measurement method for torsional shear of a hollow rock cylinder under high temperature and pressure. Background Technology

[0002] Triaxial rock testing is an important method in rock mechanics research. Its test results can more comprehensively reflect the mechanical properties of soil and rock under initial geostress conditions, which is of great significance for engineering design. With the increasing number of deep rock engineering projects in my country, complex engineering geological problems such as active faults, high geostress, high geotemperature, and underground natural gas storage have emerged. Therefore, conducting indoor mechanical experiments under different environments is an important scientific issue in the field of rock mechanics.

[0003] Currently, triaxial compression tests mainly consist of uniaxial, conventional triaxial, true triaxial, dynamic impact, and rheological tests. These methods cannot effectively simulate complex geological environments in the laboratory. For example, the test device in the Chinese patent "A Torque Shear Tester for Hollow Rock Cylinders to Improve Torque Application Accuracy" (application number: 201611029623.7) uses conventional strain gauges to measure the strain of the inner ring of the hollow cylinder, resulting in poor measurement accuracy. Furthermore, it is only applicable to a true and false triaxial torsion shear test at room temperature, and its function is relatively limited. It lacks triaxial tests that consider the coupling of multiple physical fields such as rock static load, rheology, temperature, acoustic emission, ultrasound, and resistivity.

[0004] Therefore, as engineering geological conditions gradually become more complex, it is necessary to improve the functionality of existing rock mechanics testing technologies, conduct deeper rock mechanics tests, realize multi-field coupled testing technologies for rock static load, rheology, temperature, acoustic emission, ultrasonic waves, resistivity, etc., and simultaneously realize compressed gas energy storage test research. It is also necessary to develop a multi-parameter physical measurement method for torsional shear of high-temperature and high-pressure hollow rock cylinders. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the above-mentioned background technology and to provide a method for measuring multiple physical parameters of torsional shear in a high-temperature and high-pressure hollow rock cylinder.

[0006] To achieve the above objectives, the technical solution of the present invention is: a method for measuring multiple physical parameters of torsional shear in a hollow rock cylinder under high temperature and high pressure, characterized by comprising the following steps:

[0007] Step 1: Install the hollow rock sample inside the measuring device;

[0008] Step 2: The oil delivery channel at the top of the inner cavity of the confining pressure barrel is used by the controller to deliver oil to the outer pressure. The first channel delivers oil to the cavity inside the hollow rock sample to provide inner confining pressure. The oil delivery channel of the axial loading force-applying oil cavity delivers oil to the axial force-applying oil cavity, thereby pushing the piston to apply axial force. The combined torque transmission structure drives the force transmission shaft to make circular motion to provide torque to the hollow rock sample.

[0009] Step 3: Turn on the temperature control system and use the temperature control liner to heat the measuring device. After reaching the set expected test target temperature, the temperature remains constant. Perform rock hollow cylinder torsion shear tests on samples at different temperatures. The temperature control liner wraps the force-applying oil cavity structure and the confining pressure barrel structure. The temperature control liner is connected to the temperature control console through a temperature wire. The temperature sensor is set on the inner wall of the top of the confining pressure barrel.

[0010] Step 4: When conducting acoustic emission experiments, install the acoustic emission probe, side displacement sensor, and axial displacement sensor, and complete the relevant acoustic emission tests in conjunction with the temperature-coupled torsion-shear test; the acoustic emission probe is attached to the sample surface, one end of the acoustic emission signal wire is connected to the acoustic emission probe, and the other end is connected to the acoustic emission test system; the side displacement sensor is set on the left and right sides of the sample, and the lower end of the axial displacement sensor is connected to the lower base, and the upper end is connected to the extension of the upper pressure head;

[0011] Step 5: During the ultrasonic test, the ultrasonic signal wire transmits the signal to the ultrasonic testing system to detect the waveform of the changes in the internal structure of the sample during the experiment, thus completing the relevant ultrasonic test. The test consists of an ultrasonic transmitting and receiving device, an ultrasonic signal wire, an ultrasonic clamping spring, and an ultrasonic testing system. Both ends of the sample are in contact with the ultrasonic transmitting and receiving device. The ultrasonic clamping spring is mounted on the ultrasonic transmitting and receiving device. One end of the ultrasonic signal wire is connected to the ultrasonic clamping spring, and the other end is connected to the ultrasonic testing system.

[0012] Step 6: When performing resistivity testing, after the upper electrode plate discharges onto the sample, the current is transmitted to the resistivity testing system through the lower electrode plate and the wire, thereby obtaining the change in resistivity under different environmental conditions; the upper electrode plate is installed at the upper end of the sample, and the lower electrode plate is installed at the lower end of the sample. The upper electrode plate and the lower electrode plate are respectively connected to the resistivity testing system through wires.

[0013] Step 7: During the compressed gas energy storage test, open the gas cylinder switch valve and check valve, observe the first flow rate gauge and the first flow pressure gauge, and record their values. Adjust the check valve to the target test pressure, and adjust the shut-off valve to observe the second flow rate gauge and the second flow pressure gauge until the target test pressure is reached. Simulate compressed gas energy storage tests under different environments with temperature-coupled torsion-shear tests. The gas cylinder is connected to the second channel in sequence through the first flow rate gauge, the first flow pressure gauge, and the check valve. The gas cylinder is equipped with a gas cylinder switch valve. The first channel is connected to the second flow rate gauge, the second flow pressure gauge, and the shut-off valve in sequence outside the lower base.

[0014] Step 8: Oil is supplied to the lower force-applying oil chamber through the oil supply channel to push the piston upward to unload. At the same time, oil is pumped out and unloaded in the reaction space through the oil supply channel at the bottom of the confining pressure barrel. Oil is pumped out and unloaded inside the sample through the second channel. After removing the lower base, the sample is removed to complete the multi-parameter measurement.

[0015] In the above technical solution, the measuring device includes a force-applying oil chamber structure, a pressure-containing barrel structure, and a force-transmitting structure, wherein the force-applying oil chamber structure contains a force-applying oil chamber.

[0016] The confining pressure barrel structure is located at the bottom of the force-applying oil cavity structure, and the confining pressure barrel structure contains the inner cavity of the confining pressure barrel.

[0017] The force transmission structure includes a force transmission shaft, a piston, and a combined torque transmission structure; the upper end of the force transmission shaft is connected to the combined torque transmission structure, and the lower end passes through the force application oil chamber structure, the force application oil chamber, and the confining pressure barrel structure from top to bottom, and is located inside the confining pressure barrel; the piston is fitted on the part of the force transmission shaft located in the force application oil chamber, and the piston divides the force application oil chamber into an upper force application oil chamber and a lower force application oil chamber.

[0018] The upper force-applying oil chamber, the lower force-applying oil chamber, the top of the inner cavity of the confining pressure barrel, and the bottom of the inner cavity of the confining pressure barrel are all provided with oil supply channels for connecting to external hydraulic components.

[0019] The sample is located between the lower end of the force transmission shaft and the inner wall of the bottom of the confining pressure barrel.

[0020] In the above technical solution, the lower end of the force transmission shaft is connected to an upper pressure head by a snap-fit, and a lower pressure head is provided on the inner wall of the bottom of the confining pressure barrel. The sample is located between the upper pressure head and the lower pressure head.

[0021] The confining pressure barrel structure includes a rigid sleeve, a lower base, and an upper base. The lower end of the rigid sleeve is fixed to the lower base, and the upper end is fixed to the upper base. The rigid sleeve, the lower base, and the upper base form the inner cavity of the confining pressure barrel.

[0022] The upper end of the force-applying oil cavity structure is provided with a sealing cap, and the lower end is fixedly connected to the upper base.

[0023] The first channel is connected to the upper end of the sample at one end, and the other end passes through the upper pressure head and the lower base in sequence to connect with the outside; the second channel is connected to the lower end of the sample at one end, and the other end passes through the lower pressure head and the lower base in sequence to connect with the outside.

[0024] In the above technical solution, the ultrasonic transmitting and receiving device is located at the lower end of the upper pressure head and the upper end of the lower pressure head.

[0025] In the above technical solution, in step 1, the lower end of the sample is bonded with epoxy resin to the lower pressure head, and the upper end is bonded with epoxy resin to the upper pressure head.

[0026] The rigid sleeve is sealed to the lower base to form the reaction space of the sample; the upper pressure head is snapped to the force transmission shaft, and the lower end of the force application oil cavity structure is fixedly connected to the upper base.

[0027] In the above technical solution, in step 1, the internal strain testing device is placed inside the sample and fixed; the internal strain testing device includes, from top to bottom, an LVDT shell, a conversion cone shell, and a base shell; the upper end of the LVDT is located outside the LVDT shell, and the lower end is located inside the LVDT shell; the upper end of the conversion cone is located inside the LVDT shell and contacts the lower end of the LVDT, and the lower end is located inside the conversion cone shell; the upper end of the base is located inside the base shell.

[0028] Multiple compression probes have one end in contact with the inner wall of the sample and the other end radially passing through the outer shell of the conversion cone and contacting the lower end of the conversion cone. The contact point between the compression probe and the conversion cone is an inclined platform, and a semi-compression spring is installed inside the compression probe.

[0029] In the above technical solution, the tilt angle of the tilting platform is 45°; a combined fixing shim is provided between the LVDT housing and the conversion cone housing.

[0030] The method of using the internal strain testing device in the above technical solution includes the following steps:

[0031] The compression probe is pressed against the inner wall of the sample to elongate or contract;

[0032] When the semi-compression spring contracts, the tip of the conversion cone moves towards the upper end of the inclined platform, causing the conversion cone to rise, which in turn causes the LVDT to rise.

[0033] When the semi-compression spring extends, the tip of the conversion cone moves towards the lower end of the inclined platform, causing the conversion cone to descend, which in turn drives the LVDT to descend.

[0034] The inclined platform is made at 45°, and the height at which the conversion cone rises or falls is the displacement generated in the transverse direction of the sample.

[0035] Compared with the prior art, the present invention has the following advantages:

[0036] 1) Due to the limited internal space of the sample, it is impossible to place a radial displacement sensor, but the vertical space is sufficient. Therefore, this invention designs an internal strain testing device that converts the internal radial displacement of the rock into vertical displacement, and the measurement accuracy of the inner ring strain of the sample is high.

[0037] 2) The present invention designs a temperature control system to simulate the rock strength under high temperature and high pressure geological conditions, and can carry out torsional shear tests on hollow rock cylinders under high temperature and high pressure conditions.

[0038] 3) This invention designs an ultrasonic testing system that can measure the changes in the internal structure of rock samples during the test and complete the data analysis of waveform changes during the test.

[0039] 4) This invention designs an acoustic emission testing system to measure the strain and acoustic energy accumulation of rocks under complex terrain and geological conditions, and completes the acoustic emission test during the experiment.

[0040] 5) This invention designs a resistivity testing system to determine the resistivity of rocks under complex stress paths.

[0041] 6) The temperature control system, ultrasonic testing system, acoustic emission testing system and resistivity testing system of the present invention can be freely combined and selected according to the test requirements within a small reaction space. Attached Figure Description

[0042] Figure 1 This is a schematic diagram of the structure of the present invention. Figure 1 .

[0043] Figure 2 This is a schematic diagram of the structure of the present invention. Figure 2 .

[0044] Figure 3 This is a schematic diagram of the internal strain testing device.

[0045] Figure 4 A cross-section of the internal strain testing device Figure 1 .

[0046] Figure 5 A cross-section of the internal strain testing device Figure 2 .

[0047] Wherein, A - sample, 100 - force-applying oil chamber structure, 110 - force-applying oil chamber, 111 - upper force-applying oil chamber, 112 - lower force-applying oil chamber, 120 - sealing cover, 121 - first fixing bolt, 200 - confining pressure barrel structure, 210 - confining pressure barrel inner cavity, 220 - lower pressure head, 221 - second fixing bolt, 231 - rigid sleeve, 232 - lower base, 233 - upper base, 234 - third bolt, 300 - force transmission structure, 310 - Force transmission shaft, 320 - Piston, 330 - Combined torque transmission structure, 331 - Rigid bolt, 340 - Upper indenter, 341 - Extension, 400 - Internal strain testing device, 410 - LVDT housing, 411 - LVDT, 420 - Conversion cone housing, 421 - Conversion cone, 430 - Base housing, 431 - Base, 440 - Compression probe, 441 - Inclined platform, 442 - Semi-compression spring, 450 - Combined fixing pad 510-Oil delivery channel, 520-First channel, 530-Second channel, 540-Gas cylinder switch valve, 550-Gas cylinder, 561-First flow rate gauge, 562-Second flow rate gauge, 571-First flow and pressure gauge, 572-Second flow and pressure gauge, 581-Check valve, 582-Stop valve, 610-Acoustic emission probe, 620-Acoustic emission signal wire, 630-Acoustic emission testing system, 640-Ultrasonic emission and reception device, 650-Ultrasonic signal wire, 660-Ultrasonic compression spring, 670-Ultrasonic testing system, 710-Side displacement sensor, 720-Axial displacement sensor, 800-Temperature control system, 810-Temperature control liner, 811-Temperature wire, 820-Temperature sensor, 830-Temperature control console, 900-Resistivity testing system, 910-Upper electrode plate, 920-Lower electrode plate, 930-Wire, 940-Resistivity testing system. Detailed Implementation

[0048] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings, but these descriptions are not intended to limit the invention and are merely illustrative. The advantages of the present invention will become clearer and easier to understand through this description.

[0049] Referring to the attached diagram, the method for measuring multiple physical parameters of torsional shear in a hollow rock cylinder under high temperature and pressure includes the following steps:

[0050] Step 1: Install hollow rock sample A inside the measuring device;

[0051] Step 2: The oil delivery channel 510 at the top of the inner cavity 210 of the confining pressure barrel uses a controller to deliver oil to the outer pressure, and the first channel 520 delivers oil to the cavity inside the hollow rock sample A to provide inner confining pressure; the oil delivery channel 510 of the axial loading force-applying oil cavity 111 delivers oil to the axial force-applying oil cavity, thereby pushing the piston 320 to apply axial force; the combined torque transmission structure 330 drives the force transmission shaft 310 to make circular motion to provide torque to the hollow rock sample A, and the torque application control system controls the torque application rate;

[0052] Step 3: Turn on the temperature control system 800, use the temperature control liner 810 to heat the measuring device, and after reaching the set expected test target temperature, the temperature remains constant to carry out the rock hollow cylinder torsion shear test of sample A at different temperatures; the temperature control liner 810 wraps the force-applying oil cavity structure 100 and the confining pressure barrel structure 200, and the temperature control liner 810 is connected to the temperature control console 830 through the temperature wire 811; the temperature sensor 820 is set on the top inner wall of the confining pressure barrel inner cavity 210;

[0053] Step 4: When conducting acoustic emission experiments, install the acoustic emission probe 610, side displacement sensor 710, and axial displacement sensor 720, and complete the acoustic emission test related experiments in conjunction with the temperature coupling torsion-shear test; the acoustic emission probe 610 is attached to the surface of sample A, one end of the acoustic emission signal wire 620 is connected to the acoustic emission probe 610, and the other end is connected to the acoustic emission test system 630; the side displacement sensor 710 is set on the left and right sides of sample A, and the lower end of the axial displacement sensor 720 is connected to the lower base 232, and the upper end is connected to the extension 341 of the upper pressure head 340;

[0054] Step 5: During the ultrasonic test, the ultrasonic signal wire 650 transmits the signal to the ultrasonic testing system 670 to detect the waveform of the internal structural changes of sample A during the experiment, thus completing the relevant ultrasonic test. The system includes an ultrasonic transmitting and receiving device 640, an ultrasonic signal wire 650, an ultrasonic clamping spring 660, and an ultrasonic testing system 670. Both ends of sample A are in contact with the ultrasonic transmitting and receiving device 640. The ultrasonic clamping spring 660 is mounted on the ultrasonic transmitting and receiving device 640. One end of the ultrasonic signal wire 650 is connected to the ultrasonic clamping spring 660, and the other end is connected to the ultrasonic testing system 670.

[0055] Step 6: During resistivity testing, after the upper electrode 910 discharges onto sample A, the current is transmitted to the resistivity testing system 940 through the lower electrode 920 and the wire 930, thereby obtaining the change in resistivity under different environmental conditions; the upper electrode 910 is installed on the upper end of sample A, and the lower electrode 920 is installed on the lower end of sample A. The upper electrode 910 and the lower electrode 920 are respectively connected to the resistivity testing system 940 through the wire 930.

[0056] Step 7: During the compressed gas energy storage test, open the gas cylinder switch valve 540 and the 207 check valve 581, observe the first flow rate gauge 561 and the first flow pressure gauge 571, and record their values. Adjust the check valve 581 to the test target pressure, and adjust the stop valve 582 to observe the second flow rate gauge 562 and the second flow pressure gauge 572 until the target pressure required for the test is reached. Simulate compressed gas energy storage tests under different environments with temperature-coupled torsion-shear tests. The gas cylinder 550 is connected to the second channel 530 in sequence through the first flow rate gauge 561, the first flow pressure gauge 571, and the check valve 581. The gas cylinder 550 is equipped with a gas cylinder switch valve 540. The first channel 520 is connected to the second flow rate gauge 562, the second flow pressure gauge 572, and the stop valve 582 in sequence outside the lower base 232.

[0057] Step 8: Oil is supplied to the lower force-applying oil chamber 112 through the oil supply channel 510 to push the piston 320 upward to unload. At the same time, oil is pumped out and unloaded in the reaction space through the oil supply channel 510 at the bottom of the inner cavity 210 of the confining pressure tank. Oil is pumped out and unloaded inside the sample A through the second channel 530. After removing the lower base 232, the sample A is removed to complete the multi-parameter measurement.

[0058] The measuring device includes a force-applying oil chamber structure 100, a pressure-containing barrel structure 200, and a force-transmitting structure 300, wherein the force-applying oil chamber structure 100 contains a force-applying oil chamber 110.

[0059] The confining pressure barrel structure 200 is located at the bottom of the force-applying oil cavity structure 100, and the confining pressure barrel structure 200 is the confining pressure barrel inner cavity 210.

[0060] The force transmission structure 300 includes a force transmission shaft 310, a piston 320, and a combined torque transmission structure 330. The upper end of the force transmission shaft 310 is connected to the combined torque transmission structure 330, and the lower end passes through the force application oil chamber structure 100, the force application oil chamber 110, and the confining pressure barrel structure 200 from top to bottom, and is located inside the confining pressure barrel cavity 210. The piston 320 is fitted on the part of the force transmission shaft 310 located in the force application oil chamber 110, and the piston 320 divides the force application oil chamber 110 into an upper force application oil chamber 111 and a lower force application oil chamber 112.

[0061] The upper force-applying oil chamber 111, the lower force-applying oil chamber 112, the top of the confining pressure barrel inner cavity 210, and the bottom of the confining pressure barrel inner cavity 210 are all provided with oil delivery channels 510 for connecting to external hydraulic components.

[0062] Sample A is located between the lower end of the force transmission shaft 310 and the bottom inner wall of the confining pressure barrel cavity 210.

[0063] The lower end of the force transmission shaft 310 is connected to the upper pressure head 340 by a snap fastener, and the bottom inner wall of the inner cavity 210 of the confining pressure barrel is provided with a lower pressure head 220. The sample A is located between the upper pressure head 340 and the lower pressure head 220.

[0064] The confining pressure barrel structure 200 includes a rigid sleeve 231, a lower base 232 and an upper base 233. The lower end of the rigid sleeve 231 is fixed to the lower base 232 and the upper end is fixed to the upper base 233. The rigid sleeve 231, the lower base 232 and the upper base 233 form the inner cavity 210 of the confining pressure barrel.

[0065] The upper end of the force-applying oil cavity structure 100 is provided with a sealing cover 120, and the lower end is fixedly connected to the upper base 233.

[0066] One end of the first channel 520 is connected to the upper end of sample A, and the other end passes through the upper pressure head 340 and the lower base 232 to communicate with the outside. One end of the second channel 530 is connected to the lower end of sample A, and the other end passes through the lower pressure head 220 and the lower base 232 to communicate with the outside.

[0067] The ultrasonic transmitting and receiving device 640 is located at the lower end of the upper pressure head 340 and the upper end of the lower pressure head 220.

[0068] In step 1, the lower end of sample A is bonded with epoxy resin to the lower pressure head 220 and the upper end is bonded with epoxy resin to the upper pressure head 340.

[0069] The rigid sleeve 231 is sealed with the lower base 232 to form the reaction space of sample A; the upper pressure head 340 is snapped to the force transmission shaft 310, and the lower end of the force application oil cavity structure 100 is fixedly connected to the upper base 233.

[0070] In step 1, the internal strain testing device 400 is placed inside and fixed inside the sample A; the internal strain testing device 400 includes, from top to bottom, an LVDT housing 410, a conversion cone housing 420, and a base housing 430; the upper end of the LVDT 411 is located outside the LVDT housing 410, and the lower end is located inside the LVDT housing 410; the upper end of the conversion cone 421 is located inside the LVDT housing 410 and contacts the lower end of the LVDT 411, and the lower end is located inside the conversion cone housing 421; the upper end of the base 431 is located inside the base housing 430.

[0071] Multiple compression probes 440 have one end in contact with the inner wall of sample A and the other end radially through the outer shell 420 of the conversion cone and in contact with the lower end of the conversion cone 421. The contact point between the compression probe 440 and the conversion cone 421 is an inclined platform 441. A semi-compression spring 442 is provided inside the compression probe 440.

[0072] The tilt angle of the tilting platform 441 is 45°; a combined fixing shim 450 is provided between the LVDT housing 410 and the conversion cone housing 420.

[0073] The method of using the internal strain testing device 400 includes the following steps:

[0074] The compression probe 440 presses against the inner wall of sample A to elongate or contract;

[0075] When the semi-compression spring 442 contracts, the tip of the conversion cone 421 moves towards the upper end of the inclined platform 441, causing the conversion cone 421 to rise, which in turn causes the LVDT 411 to rise.

[0076] When the semi-compression spring 442 extends, the tip of the conversion cone 421 moves towards the lower end of the inclined platform 441, causing the conversion cone 421 to descend, which in turn drives the LVDT 411 to descend.

[0077] The inclined platform 441 is made at 45°, and the height of the conversion cone 421 rising or falling is the displacement generated in the transverse direction of the sample A.

[0078] In actual use, the lower pressure head 220 is fixed to the lower base 232 by the second fixing bolt 221; the sealing cover 120 is fixed to the upper end of the force-applying oil cavity structure 100 by the first fixing bolt 121; the lower base 232 and the upper base 233 are fixedly connected by the third bolt 234; which facilitates disassembly and maintenance.

[0079] The combined torque transmission structure 330 is connected to the force transmission shaft 310 by a rigid bolt 331, so that torque is applied to the force transmission shaft 310; when the torque is applied, the entire measuring device remains stationary relative to the force transmission shaft 310 to avoid data errors.

[0080] The upper pressure head 340 and upper base 233, the lower pressure head 220 and lower base 232 are used for the entry of various test sensors.

[0081] Sealing rings are provided between the lower base 232 and the rigid sleeve 231, between the upper base 233 and the rigid sleeve 231, and between the upper base 233 and the force transmission shaft 310. The sample A is wrapped with a heat-shrink sleeve to prevent penetration.

[0082] The ultrasonic transmitting and receiving device 640 is installed on the upper pressure head 340 and the lower pressure head 220 respectively. The ultrasonic signal wire 650 transmits the signal to the ultrasonic testing system 670 to detect the waveform of the internal structural changes of the sample A during the experiment, and completes the ultrasonic test.

[0083] The internal strain testing device 400 is placed inside the sample A, and the base 431 is fixed with bolts.

[0084] The tip of the LVDT411 probe contacts the upper end of the conversion cone 421. The conversion cone housing 420 and the combined fixing pad 450 fix and guide the conversion cone 421, which receives the LVDT411 probe.

[0085] The compression probe 440 passes through the conversion cone housing 420 such that the tip of the lower end of the conversion cone 421 rests on the inclined platform 441 at the upper end of the compression probe 440; there are three compression probes 440.

[0086] The compression probe 440 contains a semi-compression spring 442, which allows the compression probe 440 to measure the inward and outward displacement of the sample A.

[0087] During the compressed gas energy storage test, the first channel 520 and the second channel 530 were converted into gas channels.

[0088] This invention simulates high and low temperatures by changing the temperature under controllable temperature conditions, and can complete the temperature-mechanical coupled torsion-shear test of a hollow cylinder by loading in both axial and horizontal directions.

[0089] In the process of controlling temperature change, this invention adds an ultrasonic testing system 670 to simulate ultrasonic testing during the torsion shear test of a hollow rock cylinder under different temperature and pressure conditions, detect the waveform generated by the rock under different test conditions, and perform ultrasonic testing.

[0090] In the process of controlling temperature change, this invention adds an acoustic emission testing system 630 to simulate acoustic emission testing during the torsion shear test of a hollow rock cylinder under different temperature and pressure conditions. Based on this, experimental research is carried out on the initiation, propagation and penetration of microcracks in rocks under multi-field coupling.

[0091] In the process of controlling temperature change, the present invention adds a resistivity testing system 940 to simulate the resistivity test during the torsion shear test of a hollow rock cylinder under different temperature and pressure conditions.

[0092] In the process of controlling temperature change, this invention adds a compressed gas energy storage test. Given that pressure and temperature have a significant impact on underground gas storage projects under complex terrain and geological conditions, a compressed gas energy storage test system is added to realize a compressed gas energy storage simulation test study that takes into account the stress principal axis rotation effect.

[0093] In summary, this invention can effectively simulate engineering construction conditions under complex underground conditions. It employs servo loading devices, temperature and air pressure loading systems, ultrasonic waves, acoustic emission, and resistivity testing methods to conduct multi-parameter physical measurement tests on the torsional shear of hollow rock cylinders under high temperature and high pressure.

[0094] All other unspecified parts belong to the prior art.

Claims

1. A method for measuring multiple physical parameters of torsional shear in a hollow rock cylinder under high temperature and pressure, characterized in that, Includes the following steps: Step 1: Install the hollow rock sample (A) inside the measuring device; Step 2: The oil delivery channel (510) at the top of the inner cavity (210) of the confining pressure barrel uses the controller to deliver oil to the outer pressure. The first channel (520) delivers oil to the cavity inside the hollow rock sample (A) to provide inner confining pressure. The oil delivery channel (510) of the axial loading force-applying oil cavity (111) delivers oil to the axial force-applying oil cavity, thereby pushing the piston (320) to apply axial force. The combined torque transmission structure (330) drives the force transmission shaft (310) to make circular motion to provide torque to the hollow rock sample (A). Step 3: Turn on the temperature control system (800), use the temperature control liner (810) to heat the measuring device, and after reaching the set expected test target temperature, the temperature remains constant to carry out the rock hollow cylinder torsion shear test of the sample (A) at different temperatures; the temperature control liner (810) wraps the force-applying oil cavity structure (100) and the confining pressure barrel structure (200), and the temperature control liner (810) is connected to the temperature control console (830) through the temperature wire (811); the temperature sensor (820) is set on the top inner wall of the confining pressure barrel cavity (210); Step 4: When conducting acoustic emission experiments, install the acoustic emission probe (610), side displacement sensor (710), and axial displacement sensor (720), and complete the acoustic emission test related experiments in conjunction with the temperature coupling torsion shear test; the acoustic emission probe (610) is attached to the surface of the sample (A), one end of the acoustic emission signal wire (620) is connected to the acoustic emission probe (610), and the other end is connected to the acoustic emission test system (630); the side displacement sensor (710) is set on the left and right sides of the sample (A), and the lower end of the axial displacement sensor (720) is connected to the lower base (232), and the upper end is connected to the extension (341) of the upper pressure head (340); Step 5: During the ultrasonic test, the ultrasonic signal wire (650) transmits the signal to the ultrasonic testing system (670) to detect the waveform of the internal structural changes of the sample (A) during the experiment, and completes the relevant ultrasonic test; ultrasonic transmitting and receiving device (640), ultrasonic signal wire (650), ultrasonic clamping spring (660) and ultrasonic testing system (670); both the upper and lower ends of the sample (A) are in contact with the ultrasonic transmitting and receiving device (640), the ultrasonic clamping spring (660) is set on the ultrasonic transmitting and receiving device (640), one end of the ultrasonic signal wire (650) is connected to the ultrasonic clamping spring (660) and the other end is connected to the ultrasonic testing system (670); Step 6: During resistivity testing, after the upper electrode (910) discharges onto the sample (A), the current is transmitted to the resistivity testing system (940) through the lower electrode (920) and the wire (930), thereby obtaining the change in resistivity under different environmental conditions; the upper electrode (910) is installed on the upper end of the sample (A), and the lower electrode (920) is installed on the lower end of the sample (A). The upper electrode (910) and the lower electrode (920) are respectively connected to the resistivity testing system (940) through the wire (930); Step 7: When conducting the compressed gas energy storage test, open the gas cylinder switch valve (540) and the 207 check valve (581), observe the first flow rate gauge (561) and the first flow pressure gauge (571), record their values, adjust the check valve (581) to the test target pressure, and adjust the stop valve (582) to observe the second flow rate gauge (562) and the second flow pressure gauge (572) until the test target pressure is reached; simulate compressed gas energy storage test under different environments with temperature-coupled torsion shear test; the gas cylinder (550) is connected to the second channel (530) in sequence through the first flow rate gauge (561), the first flow pressure gauge (571), and the check valve (581), and the gas cylinder (550) is equipped with a gas cylinder switch valve (540); the first channel (520) is connected to the second flow rate gauge (562), the second flow pressure gauge (572) and the stop valve (582) in sequence outside the lower base (232); Step 8: Oil is supplied to the lower force-applying oil chamber (112) through the oil supply channel (510) to push the piston (320) to move upward for unloading. At the same time, oil is pumped out and unloaded in the reaction space through the oil supply channel (510) at the bottom of the inner cavity (210) of the confining pressure barrel. Oil is pumped out and unloaded inside the sample (A) through the second channel (530). After removing the lower base (232), the sample (A) is removed to complete the multi-parameter measurement.

2. A method for measuring multiple physical parameters of torsional shear in a hollow rock cylinder under high temperature and pressure, characterized in that: The measuring device includes a force-applying oil chamber structure (100), a pressure-containing barrel structure (200), and a force transmission structure (300), wherein the force-applying oil chamber structure (100) contains a force-applying oil chamber (110); The confining pressure barrel structure (200) is located at the bottom of the force-applying oil cavity structure (100), and the confining pressure barrel structure (200) contains the confining pressure barrel inner cavity (210); The force transmission structure (300) includes a force transmission shaft (310), a piston (320), and a combined torque transmission structure (330); the upper end of the force transmission shaft (310) is connected to the combined torque transmission structure (330), and the lower end passes through the force application oil chamber structure (100), the force application oil chamber (110), and the confining pressure barrel structure (200) from top to bottom, and is located in the inner cavity (210) of the confining pressure barrel; the piston (320) is fitted on the part of the force transmission shaft (310) located in the force application oil chamber (110), and the piston (320) divides the force application oil chamber (110) into an upper force application oil chamber (111) and a lower force application oil chamber (112); The upper force-applying oil chamber (111), the lower force-applying oil chamber (112), the top of the confining pressure barrel inner cavity (210), and the bottom of the confining pressure barrel inner cavity (210) are all provided with oil supply channels (510) for connecting with external hydraulic components; The sample (A) is located between the lower end of the force transmission shaft (310) and the bottom inner wall of the confining pressure barrel cavity (210).

3. The method for measuring multiple physical parameters of torsional shear in a high-temperature, high-pressure hollow rock cylinder according to claim 2, characterized in that: The lower end of the force transmission shaft (310) is connected to an upper pressure head (340) by a snap fastener, and a lower pressure head (220) is provided on the bottom inner wall of the inner cavity (210) of the confining pressure barrel. The sample (A) is located between the upper pressure head (340) and the lower pressure head (220). The confining pressure barrel structure (200) includes a rigid sleeve (231), a lower base (232) and an upper base (233). The lower end of the rigid sleeve (231) is fixed to the lower base (232) and the upper end is fixed to the upper base (233). The rigid sleeve (231), the lower base (232) and the upper base (233) form the inner cavity (210) of the confining pressure barrel. The upper end of the force-applying oil cavity structure (100) is provided with a sealing cap (120), and the lower end is fixedly connected to the upper base (233); One end of the first channel (520) is connected to the upper end of the sample (A), and the other end passes through the upper pressure head (340) and the lower base (232) to communicate with the outside. One end of the second channel (530) is connected to the lower end of the sample (A), and the other end passes through the lower pressure head (220) and the lower base (232) to communicate with the outside.

4. The method for measuring multiple physical parameters of torsional shear in a high-temperature, high-pressure hollow rock cylinder according to claim 3, characterized in that: The ultrasonic transmitting and receiving device (640) is located at the lower end of the upper pressure head (340) and the upper end of the lower pressure head (220).

5. The method for measuring multiple physical parameters of torsional shear in a high-temperature, high-pressure hollow rock cylinder according to claim 4, characterized in that: In step 1, the lower end of sample A is bonded with epoxy resin to the lower pressure head 220 and the upper end is bonded with epoxy resin to the upper pressure head 340. The rigid sleeve 231 is sealed with the lower base 232 to form the reaction space of sample A; the upper pressure head 340 is snapped to the force transmission shaft 310, and the lower end of the force application oil cavity structure 100 is fixedly connected to the upper base 233.

6. The method for measuring multiple physical parameters of torsional shear in a high-temperature, high-pressure hollow rock cylinder according to claim 5, characterized in that: In step 1, the internal strain testing device (400) is placed inside and fixed inside the sample A; the internal strain testing device (400) includes, from top to bottom, an LVDT shell (410), a conversion cone shell (420), and a base shell (430); the upper end of the LVDT (411) is located outside the LVDT shell (410), and the lower end is located inside the LVDT shell (410); the upper end of the conversion cone (421) is located inside the LVDT shell (410) and contacts the lower end of the LVDT (411), and the lower end is located inside the conversion cone shell (420); the upper end of the base (431) is located inside the base shell (430); Multiple compression probes (440) have one end in contact with the inner wall of the sample (A) and the other end radially through the outer shell (420) of the conversion cone and in contact with the lower end of the conversion cone (421). The contact point between the compression probe (440) and the conversion cone (421) is an inclined platform (441). A semi-compression spring (442) is provided inside the compression probe (440).

7. The method for measuring multiple physical parameters of torsional shear in a high-temperature, high-pressure hollow rock cylinder according to claim 6, characterized in that: The tilting angle of the tilting platform (441) is 45°; a combined fixing shim (450) is provided between the LVDT housing (410) and the conversion cone housing (420).

8. The method for measuring multiple physical parameters of torsional shear in a high-temperature, high-pressure hollow rock cylinder according to claim 7, characterized in that: The method of using the internal strain testing device (400) includes the following steps: The compression probe (440) presses against the inner wall of the sample (A) to elongate or contract; When the semi-compression spring (442) contracts, the tip of the conversion cone (421) moves towards the upper end of the inclined platform (441), causing the conversion cone (421) to rise, which in turn causes the LVDT (411) to rise. When the semi-compression spring (442) extends, the tip of the conversion cone (421) moves towards the lower end of the inclined platform (441), causing the conversion cone (421) to descend, which in turn drives the LVDT (411) to descend. The inclined platform (441) is made at 45°, and the height of the conversion cone (421) rising or falling is the displacement generated in the transverse direction of the specimen (A).

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