A salt rock creep damage test device for multi-source signal synchronous acquisition

Abstract

The application relates to the fields of rock mechanics experiments and underground hydrogen storage technology, and discloses a salt rock creep damage test device for multi-source signal synchronous acquisition, wherein the outer shell is provided with a pressure chamber for testing a sample; an axial pressure loading system is used for applying axial load to the sample; a confining pressure loading system is used for applying confining pressure to the sample; a signal monitoring system is used for collecting multi-source signals of the sample, and the signal monitoring system comprises a displacement sensor, a plurality of ultrasonic probes, a plurality of acoustic emission probes and a resistivity testing system; a temperature control system is used for controlling a temperature environment in a test process; and a synchronous control unit is used for controlling synchronous operation and data collection of the axial pressure loading system, the confining pressure loading system, the signal monitoring system and the temperature control system. The application can solve the technical problems of single monitoring signal, asynchronous collection, non-realistic temperature simulation and lack of intelligent control in the prior art.

Description

Technical Field

[0001] This invention relates to the fields of rock mechanics experiments and underground hydrogen storage technology, and in particular to a salt rock creep damage test device for synchronous acquisition of multi-source signals. Background Technology

[0002] Salt rock is a typical nonlinear viscoplastic material, widely distributed in engineering scenarios such as underground salt cavern gas storage, oil storage, and nuclear waste disposal. Due to the significant creep and damage evolution behavior of salt rock under long-term loading conditions, its mechanical properties and stability directly affect the safe operation and service life of underground storage facilities. To study the mechanical response of salt rock under complex stress conditions, it is usually necessary to accurately characterize its creep properties and damage mechanisms through laboratory experiments.

[0003] Problems with existing technology: First, the monitoring signals are singular and cannot fully reflect the damage evolution. Most existing salt rock creep test devices adopt single signal monitoring methods, such as traditional mechanical measurement methods such as strain, stress or displacement. They can only obtain macroscopic deformation information on the sample surface and cannot capture multidimensional information on the initiation and propagation of microcracks inside the material, thus failing to fully reflect the damage evolution process inside the salt rock.

[0004] Second, asynchronous acquisition of multi-source signals makes data fusion difficult. Although some studies have introduced acoustic emission (AE), resistivity or temperature signal monitoring to obtain information on internal material damage, these monitoring systems are often physically separated from the loading device. Each signal acquisition system operates independently and lacks a unified time reference, resulting in asynchronous signal acquisition and difficulty in data fusion, making it impossible to achieve real-time collaborative analysis of multi-source signals during creep.

[0005] Third, the temperature simulation is not realistic and cannot reflect the deep environment. The temperature control of existing test devices mostly adopts external heating or cooling methods, which cannot accurately simulate the high temperature environment at the bottom of deep salt caves. Moreover, the coupling effect between the temperature field and the stress field is poor, making it difficult to realistically reproduce the mechanical behavior of deep salt rocks under long-term loads under laboratory conditions.

[0006] Fourth, the loading accuracy is low and there is a lack of intelligent control. The loading system and monitoring system of traditional test devices lack an effective feedback linkage mechanism, which makes it impossible to achieve intelligent loading control based on real-time monitoring data. The loading accuracy and stability are insufficient, making it difficult to meet the requirements of long-term creep test for loading continuity and accuracy.

[0007] Therefore, there is an urgent need to develop a new type of salt rock creep damage testing device that can integrate multi-source sensing modules, realize synchronous signal acquisition and fusion analysis, and have intelligent loading control functions, in order to solve the technical problems in the existing technology such as single monitoring signal, asynchronous acquisition, unrealistic temperature simulation and lack of intelligent control. Summary of the Invention

[0008] The purpose of this invention is to provide a salt rock creep damage testing device for synchronous acquisition of multi-source signals, aiming to solve or improve at least one of the above-mentioned technical problems. It integrates multi-source sensing modules, realizes synchronous signal acquisition and fusion analysis, and has intelligent loading control function, so as to solve the technical problems in the prior art such as single monitoring signal, asynchronous acquisition, unrealistic temperature simulation and lack of intelligent control.

[0009] To achieve the above objectives, the present invention provides the following solution: The present invention provides a salt rock creep damage testing device for multi-source signal synchronous acquisition, comprising: The outer casing is equipped with a pressure chamber for testing the sample; An axial compression loading system is used to apply an axial load to the specimen; A confining pressure loading system is used to apply confining pressure to the specimen; The signal monitoring system is used to acquire multi-source signals of the sample, including a displacement sensor, multiple ultrasonic probes, multiple acoustic emission probes, and a resistivity testing system. Temperature control system, used to control the temperature environment during the test; The synchronization control unit is used to control the synchronous operation and data acquisition of the axial pressure loading system, the confining pressure loading system, the signal monitoring system, and the temperature control system.

[0010] Optionally, the axial pressure loading system includes an upper pressure head and a lower pressure head, both of which have graphene blocks embedded inside. The graphene blocks are hollow inside and are used to inject fluid through a first hydraulic pump and a first oil tank.

[0011] Optionally, the pressing head is provided with multiple acoustic emission interfaces and multiple ultrasonic interfaces for connecting the acoustic emission probe and the ultrasonic probe.

[0012] Optionally, the displacement sensor has an I-shaped structure, with its axial rod used to monitor the axial displacement of the sample and its transverse rod used to monitor the transverse displacement of the sample.

[0013] Optionally, the resistivity testing system includes a resistivity signal acquisition unit and two sets of graphene electrodes. The two sets of graphene electrodes are respectively embedded in a pair of graphene blocks, forming a closed circuit with the sample, for real-time monitoring of the resistivity change of the sample.

[0014] Optionally, the temperature control system includes a temperature sensor, a confining pressure temperature controller, a temperature control center, and a pressure head temperature controller, which are used to control the confining pressure oil temperature, the overall temperature regulation, and the pressure head oil temperature, respectively.

[0015] Optionally, the axial load system further includes an axial loading device, an axial sensor, an electric lead screw driver, and an axial control center for precise control and data recording of the axial load.

[0016] Optionally, the confining pressure loading system includes a second oil injection port, a second hydraulic pump, a second oil tank, a confining pressure sensor, a confining pressure controller, and a confining pressure control center, for applying, controlling, and monitoring the confining pressure, wherein the second oil injection port is located on the pressure chamber.

[0017] Optionally, the signal monitoring system further includes an ultrasonic signal collector and an acoustic emission signal collector, which are used to receive and process the signals collected by the ultrasonic probe and the acoustic emission probe, respectively.

[0018] Optionally, the ultrasonic probe is externally connected to the outside of the upper pressure head and the lower pressure head, and the acoustic emission probe is embedded in the displacement sensor.

[0019] The present invention discloses the following technical effects: This invention constructs a multi-physics field signal synchronous acquisition system by integrating multiple sensing modules such as stress, strain, acoustic emission, electrical signals, ultrasound, and temperature. The synchronous control unit provides unified triggering and coordinated control for each system, ensuring that all signal acquisition systems have a unified time reference, significantly improving the timeliness and consistency of the data. Through the fusion analysis of multi-source signals, it can comprehensively reflect the damage and deformation evolution laws within salt rock, overcoming the shortcomings of existing technologies that rely on single monitoring signals and cannot comprehensively characterize damage evolution.

[0020] This invention organically combines an axial compression loading system, a confining pressure loading system, and a signal monitoring system to form a compact, integrated structure. Graphene blocks are embedded inside the upper and lower pressure heads, serving both as a heat-conducting medium for temperature control and as electrodes for resistivity monitoring, achieving an integrated design of structure and function. This integrated layout simplifies the experimental operation process, reduces system errors, and improves overall reliability and experimental efficiency.

[0021] This invention employs an upper and lower pressure head structure with a hollow interior and embedded graphene blocks. A temperature-controlled fluid is injected into the pressure head via a hydraulic pump and oil tank. Utilizing the excellent thermal conductivity of graphene, precise temperature control of the sample tip is achieved. Simultaneously, the confining pressure loading system is equipped with an independent temperature control loop, capable of simulating both the ambient temperature of the bottom layer and the axial temperature of the bottom layer, more realistically reproducing the temperature environment of deep salt caverns. This is suitable for simulating the long-term creep and damage evolution processes of salt rocks.

[0022] This invention constructs an intelligent loading control system based on multi-source feedback signals through a synchronous control unit. It can automatically adjust loading parameters according to real-time monitored signals such as stress, strain, and acoustic emission, thereby achieving automatic adjustment and stable control of the loading process. This ensures the continuity and accuracy of stress or strain loading, overcoming the problems of low loading accuracy and lack of intelligent control in existing technologies. Attached Figure Description

[0023] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the pressure head structure of the present invention.

[0024] In the diagram: 1. Outer shell; 2. Pressure chamber; 3. Axial loading device; 4. Axial sensor; 5. Electric lead screw driver; 6. Axial control center; 7. Upper pressure head; 8. Lower pressure head; 9. First graphene block; 10. Second graphene block; 11. Temperature sensor; 12. Confining pressure temperature controller; 13. Temperature control center; 14. Second oil injection port; 15. Second hydraulic pump; 16. Second oil tank; 17. Displacement sensor; 18. Ultrasonic probe; 19. Upper acoustic emission probe; 20. Lower ultrasonic probe; 21. Lower acoustic emission probe; 22. Ultrasonic signal acquisition device; 3. Acoustic emission signal acquisition device; 24. Confining pressure sensor; 25. Confining pressure controller; 26. Confining pressure control center; 27. Indenter temperature controller; 28. First hydraulic pump; 29. ​​First oil tank; 30. Resistivity signal acquisition device; 31. Graphene electrode; 32. Sample; 33. Third oil injection port; 34. First acoustic emission interface; 35. Second acoustic emission interface; 36. Third acoustic emission interface; 37. Fourth acoustic emission interface; 38. First oil injection port; 39. First ultrasonic interface; 40. Second ultrasonic interface; 41. Third ultrasonic interface; 42. Fourth ultrasonic interface. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0027] Reference Figures 1 to 2 This invention provides a multi-source signal synchronous acquisition salt rock creep damage testing device, comprising: The outer casing 1 is provided with a pressure chamber 2 for testing the sample 32; Axial compression loading system is used to apply axial load to specimen 32; A confining pressure loading system is used to apply confining pressure to specimen 32; The signal monitoring system is used to acquire multi-source signals from the sample 32, including displacement sensor 17, multiple ultrasonic probes, multiple acoustic emission probes, and resistivity testing system; Temperature control system, used to control the temperature environment during the test; The synchronization control unit is used to control the synchronous operation and data acquisition of the axial compression loading system, confining pressure loading system, signal monitoring system, and temperature control system.

[0028] The graphene block serves a dual function of thermal and electrical conductivity, acting as both a temperature conduction medium for sample end temperature control and an electrode material for resistivity monitoring. This significantly improves the functional integration of the indenter structure and reduces the interference of additional components on the sample stress state. Utilizing graphene's excellent in-plane thermal conductivity, rapid and uniform temperature distribution at the indenter-sample contact surface can be achieved, avoiding measurement errors caused by local temperature gradients and improving the accuracy of temperature simulation. Integrating the temperature control channel and electrodes inside the indenter avoids the space occupied by external heating devices in the pressure chamber, making the device structure more compact and facilitating the placement of more sensors within a limited space.

[0029] Furthermore, the multiple ultrasonic probes are designated as an upper ultrasonic probe 18 and a lower ultrasonic probe 20.

[0030] Furthermore, the multiple acoustic emission probes are designated as upper acoustic emission probe 19 and lower acoustic emission probe 21.

[0031] In one embodiment of the present invention, the axial compression loading system includes an upper pressure head 7 and a lower pressure head 8, both of which have graphene blocks embedded inside. The graphene blocks are hollow inside and are used to inject fluid through a first hydraulic pump 28 and a first oil tank 29.

[0032] Furthermore, the two graphene blocks are the first graphene block 9 and the second graphene block 10, respectively.

[0033] Furthermore, the lower pressure head 8 is also provided with a first oil injection hole 38, and the upper pressure head 7 is also provided with a third oil injection hole 33.

[0034] Furthermore, the synchronization control unit consists of an industrial PC (IPC) combined with a data acquisition module, preferably an industrial PC + NIPXIe system + LabVIEW, and its core function is time base unification and coordinated triggering.

[0035] In one embodiment of the present invention, the pressure head 8 is provided with multiple acoustic emission interfaces and multiple ultrasonic interfaces for connecting the acoustic emission probe and the ultrasonic probe.

[0036] Furthermore, the multiple acoustic emission interfaces are designated as a first acoustic emission interface 34, a second acoustic emission interface 35, a third acoustic emission interface 36, and a fourth acoustic emission interface 37.

[0037] Furthermore, the multiple ultrasonic interfaces are designated as a first ultrasonic interface 39, a second ultrasonic interface 40, a third ultrasonic interface 41, and a fourth ultrasonic interface 42.

[0038] The arrangement of multiple acoustic emission and ultrasonic interfaces enables multi-directional and multi-angle acquisition of sample damage signals, improving the spatial resolution of acoustic emission source localization and ultrasonic imaging, and enabling more accurate tracking of crack initiation location and propagation path. The integrated interface design of the indenter head 8 shortens the transmission path between the probe and the signal acquisition unit, reducing signal attenuation and electromagnetic interference, ensuring effective capture of weak acoustic emission signals and high-fidelity transmission of ultrasonic signals. The standardized interface design facilitates rapid probe installation, replacement, and calibration, improving test preparation efficiency while ensuring consistency in sensor placement across different batches of tests, thus enhancing data comparability.

[0039] In one embodiment of the present invention, the displacement sensor 17 has an I-shaped structure, with its axial rod used to monitor the axial displacement of the sample and its transverse rod used to monitor the transverse displacement of the sample.

[0040] The I-shaped structure enables simultaneous monitoring of the axial and lateral deformation of the sample using a single sensor, avoiding spatial interference and inconsistent measurement benchmarks caused by multiple independent sensors. This ensures the temporal synchronicity and spatial correspondence of deformation data in both directions. By simultaneously acquiring axial and lateral strain, the volumetric strain of the sample can be directly calculated, providing direct data support for studying the volumetric change patterns (such as dilatation or compaction) during salt rock creep. Based on the synchronously monitored axial and lateral displacement data, the dynamic Poisson's ratio of the material can be calculated in real time, providing key parameters for determining the material damage state and inverting constitutive model parameters.

[0041] In one embodiment of the present invention, the resistivity testing system includes a resistivity signal acquisition unit 30 and two sets of graphene electrodes 31. The two sets of graphene electrodes 31 are respectively embedded in a pair of graphene blocks and form a closed circuit with the sample 32 for real-time monitoring of the resistivity change of the sample.

[0042] Resistivity monitoring, as a non-destructive testing method, can reflect changes in the internal pore structure and microcrack development of sample 32 in real time without interrupting loading or damaging the sample 32, thus overcoming the limitation of mechanical monitoring, which can only reflect macroscopic deformation. During the creep damage process of salt rock, the generation and propagation of internal microcracks lead to significant changes in resistivity. By monitoring resistivity changes in real time, the accumulation of internal damage in the material can be predicted in advance, capturing the damage initiation moment earlier than acoustic emission signals. The graphene electrode 31 is in direct contact with the end face of sample 32. Utilizing the excellent conductivity and chemical stability of graphene, a stable ohmic contact is ensured between the electrode and the sample during long-term creep tests, avoiding the impact of contact resistance fluctuations on measurement accuracy.

[0043] In one embodiment of the present invention, the temperature control system includes a temperature sensor 11, a confining pressure temperature controller 12, a temperature control center 13, and a pressure head temperature controller 27, which are used to control the confining pressure oil temperature, the overall temperature regulation, and the pressure head oil temperature, respectively.

[0044] The separate design of the confining pressure temperature controller 12 and the pressure head temperature controller 27 enables independent control of the temperature of the confining pressure medium and the axial temperature of the sample 32. This allows for the simulation of temperature environments at different locations in deep salt caverns (around the wellbore and deep within the salt layer), improving the flexibility of temperature simulation. By setting the temperature difference between the confining pressure oil temperature and the pressure head oil temperature, a controllable temperature gradient can be formed inside the sample 32. This simulates the non-uniform temperature field caused by geothermal gradients and injection-production heat effects during actual reservoir operation, and allows for the study of creep damage behavior under temperature-stress coupling. The temperature control center 13 can adjust the temperature of each loop in real time based on the experimental plan or monitoring data feedback, achieving accurate reproduction of complex temperature histories, such as simulating temperature fluctuations or seasonal temperature changes during hydrogen injection into the reservoir.

[0045] In one embodiment of the present invention, the axial load system further includes an axial loading device 3, an axial sensor 4, an electric lead screw driver 5, and an axial control center 6, for achieving precise control and data recording of the axial load.

[0046] The electric lead screw driver 5, in conjunction with the axial sensor 4, forms a closed-loop control system, enabling high-precision, high-resolution control of axial load or displacement. This meets the stability requirements of creep tests for long-term constant stress or constant strain loading. The axial control center 6 supports multiple loading modes, including force control, displacement control, and strain control, and can smoothly switch between modes to adapt to loading needs under different research objectives. For example, it can initially use force control to load to the target value and then switch to strain control to maintain the load. The axial control center 6 records parameters such as force, displacement, and time in real time during the loading process, sharing a time reference with the synchronous control unit. This ensures accurate correspondence between mechanical data and multi-source monitoring data, providing a complete data chain for subsequent data analysis.

[0047] In one embodiment of the present invention, the confining pressure loading system includes a second oil injection port 14, a second hydraulic pump 15, a second oil tank 16, a confining pressure sensor 24, a confining pressure controller 25, and a confining pressure control center 26, for applying, controlling, and monitoring confining pressure. The second oil injection port 14 is located on the pressure chamber 2.

[0048] The confining pressure loading system, in conjunction with the axial pressure loading system, can simulate the triaxial stress state of specimen 32 under the combined action of axial and confining pressures, more realistically reflecting the complex stress environment of deep salt rock and overcoming the limitation of uniaxial tests that cannot consider lateral constraints. The confining pressure controller 24 is independent of the axial control center 6, enabling separate control and coordinated loading of axial and confining pressures, supporting various stress path tests, such as axial loading under constant confining pressure and true triaxial tests with simultaneous increases in axial and confining pressures. The design of the second oil injection hole 14 on the pressure chamber 2 facilitates the injection and discharge of the confining pressure medium, and allows for the replenishment or replacement of hydraulic oil during the test, maintaining the sealing of the pressure chamber 2 and the stability of the confining pressure system.

[0049] In one embodiment of the present invention, the signal monitoring system further includes an ultrasonic signal acquisition unit 22 and an acoustic emission signal acquisition unit 23, which are used to receive and process the signals acquired by the ultrasonic probe and the acoustic emission probe, respectively.

[0050] The ultrasonic signal acquisition unit 22 and the acoustic emission signal acquisition unit 23 are optimized for the different characteristics of the two signals, respectively. The ultrasonic acquisition unit 22 has high-frequency broadband reception capability, suitable for the accurate acquisition of ultrasonic transmission and reflection signals; the acoustic emission acquisition unit 23 has high sensitivity and low noise characteristics, suitable for the detection and parameter extraction of weak acoustic emission events. The dedicated acquisition unit has a built-in digital signal processing module, which can perform signal filtering, amplification, and characteristic parameter extraction in real time, reducing data transmission volume and improving system response speed. The two acquisition units achieve unified triggering and clock synchronization through a synchronization control unit, ensuring strict alignment of ultrasonic detection and acoustic emission monitoring on the time axis, facilitating multi-signal fusion analysis, such as using acoustic emission event localization to guide the pinpoint detection of ultrasonic waves. In one embodiment of the present invention, the ultrasonic probe is externally connected to the outside of the upper pressure head 7 and the lower pressure head 8, and the acoustic emission probe is embedded in the displacement sensor 17.

[0051] The ultrasonic probe is externally connected to the upper pressure head 7 and the lower pressure head 8, facilitating adjustment of the probe position and angle according to experimental requirements, enabling targeted detection of different areas of the sample 32. The acoustic emission probe is embedded in the displacement sensor 17, close to the surface of the sample 32, improving the sensitivity of detecting internal damage events in the sample 32. The differentiated arrangement of the ultrasonic probe and the acoustic emission probe effectively avoids mutual interference between the two types of signals in the transmission path. The ultrasonic signal propagates through the solid medium of the pressure head, while the acoustic emission signal is directly coupled through the surface of the sample 32, ensuring the signal quality of each. This arrangement makes full use of the space outside the pressure head and inside the pressure chamber 2, avoiding crowded probe arrangement, ensuring effective working space for each sensor, and facilitating observation and operation maintenance during the experiment.

[0052] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0053] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A multi-source signal synchronous acquisition salt rock creep damage testing device, characterized in that, include: The outer shell (1) is provided with a pressure chamber (2) for testing the sample (32); An axial compression loading system is used to apply an axial load to the specimen (32); A confining pressure loading system for applying confining pressure to the specimen (32); The signal monitoring system is used to collect multi-source signals of the sample (32), including a displacement sensor (17), multiple ultrasonic probes, multiple acoustic emission probes and a resistivity testing system; Temperature control system, used to control the temperature environment during the test; The synchronization control unit is used to control the synchronous operation and data acquisition of the axial pressure loading system, the confining pressure loading system, the signal monitoring system, and the temperature control system.

2. The salt rock creep damage testing device for multi-source signal synchronous acquisition according to claim 1, characterized in that, The axial pressure loading system includes an upper pressure head (7) and a lower pressure head (8). Both the upper pressure head (7) and the lower pressure head (8) are embedded with graphene blocks. The graphene blocks are hollow inside and are used to inject fluid through a first hydraulic pump (28) and a first oil tank (29).

3. The salt rock creep damage testing device for multi-source signal synchronous acquisition according to claim 2, characterized in that, The pressure head (8) is provided with multiple acoustic emission interfaces and multiple ultrasonic interfaces for connecting the acoustic emission probe and the ultrasonic probe.

4. The salt rock creep damage testing device for multi-source signal synchronous acquisition according to claim 1, characterized in that, The displacement sensor (17) has an I-shaped structure, with its axial rod used to monitor the axial displacement of the sample and its transverse rod used to monitor the transverse displacement of the sample.

5. The salt rock creep damage testing device for multi-source signal synchronous acquisition according to claim 2, characterized in that, The resistivity testing system includes a resistivity signal acquisition unit (30) and two sets of graphene electrodes (31). The two sets of graphene electrodes (31) are respectively embedded in a pair of graphene blocks, forming a closed circuit with the sample (32) for real-time monitoring of the resistivity change of the sample.

6. The salt rock creep damage testing device for multi-source signal synchronous acquisition according to claim 1, characterized in that, The temperature control system includes a temperature sensor (11), a confining pressure temperature controller (12), a temperature control center (13), and a pressure head temperature controller (27), which are used to control the confining pressure oil temperature, the overall temperature regulation, and the pressure head oil temperature, respectively.

7. The salt rock creep damage testing device for multi-source signal synchronous acquisition according to claim 1, characterized in that, The axial load system also includes an axial loading device (3), an axial sensor (4), an electric lead screw driver (5), and an axial control center (6) for achieving precise control and data recording of axial load.

8. The salt rock creep damage testing device for multi-source signal synchronous acquisition according to claim 1, characterized in that, The confining pressure loading system includes a second oil injection port (14), a second hydraulic pump (15), a second oil tank (16), a confining pressure sensor (24), a confining pressure controller (25), and a confining pressure control center (26), which are used to apply, control, and monitor the confining pressure. The second oil injection port (14) is located on the pressure chamber.

9. The salt rock creep damage testing device for multi-source signal synchronous acquisition according to claim 1, characterized in that, The signal monitoring system also includes an ultrasonic signal collector (22) and an acoustic emission signal collector (23), which are used to receive and process the signals collected by the ultrasonic probe and the acoustic emission probe, respectively.

10. The salt rock creep damage testing device for multi-source signal synchronous acquisition according to claim 2, characterized in that, The ultrasonic probe is externally connected to the upper pressure head (7) and the lower pressure head (8), and the acoustic emission probe is embedded in the displacement sensor (17).

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