A servo-controlled continuous variable stiffness loading experimental system for deep coal and rock mass dynamic hazards

Abstract

The present invention discloses a servo-controlled continuous stiffness loading experimental system for deep coal-rock dynamic disasters, and relates to the technical field of deep engineering dynamic disaster simulation. In order to solve the problem that existing experimental equipment is difficult to simultaneously realize servo and continuously stiffness-changing loading to truly simulate coal-rock dynamic disasters, the following technical scheme is proposed: comprising an electro-hydraulic servo rock mechanics experimental system, an electromagnetic variable stiffness loader, a monitoring system, and an electronic control system; the rock mechanics experimental system applies external loads in a servo-controlled loading manner; the electromagnetic variable stiffness loader comprises a loading rod and a load-bearing platform; the monitoring system is used to monitor the entire process of coal-rock dynamic disaster incubation and occurrence in real time; the electronic control system can realize continuous and automatic changes in the stiffness of the coal-rock loading system. The servo-controlled continuous stiffness loading experimental system of the present invention can quantitatively calculate the energy input to the coal-rock by the loading system and automatically and continuously change the stiffness loading to adapt to the stress environment of the coal-rock mass in deep engineering.

Description

Technical Field

[0001] The present invention relates to the technical field of deep engineering dynamic disaster simulation, and in particular to a deep coal rock mass dynamic disaster servo continuous variable stiffness loading experimental system. Background Art

[0002] With the gradual depletion of surface and shallow mineral resources, deeper mining has become an inevitable trend in mineral resource development. However, deep mining faces numerous challenges, including high ground stress, complex geological conditions, and disturbances caused by mining activities, all of which are significant factors that can trigger dynamic hazards in coal and rock masses. These dynamic hazards, such as rock bursts, rockbursts, and mine tremors, not only threaten the lives of miners but also severely restrict the efficiency and safety of deep-seated mineral mining.

[0003] Currently, the scientific community has yet to fully understand the mechanisms of dynamic disasters in deep coal and rock masses. Therefore, there is an urgent need to realistically simulate the causative factors and environment in laboratory settings to further investigate their mechanisms. Mining activities are one of the primary causes of dynamic disasters in coal and rock masses. During mining, coal and rock masses are subject to stress redistribution, including radial stress unloading and tangential stress concentration, while also reducing the local stiffness of the surrounding rock. This stress redistribution and change in stiffness create the conditions for the occurrence of dynamic disasters.

[0004] Although some experimental devices have been developed to simulate the mechanical environment of deep coal and rock mass dynamic hazards, these devices still have some shortcomings. For example, the energy storage device in some devices is directly connected to the external load application system, which can cause the experimental results to be affected by the stiffness of the external load application system, thus failing to accurately reflect the dynamic response of the coal and rock mass under real mining conditions. In addition, the design of variable stiffness loading devices is complex, bulky, and expensive, and continuous variable stiffness loading is difficult to achieve. This limits the accuracy and practicality of experimental systems in simulating the entire process of deep coal and rock mass dynamic hazards.

[0005] Therefore, in order to further study the mechanism of dynamic disasters in deep coal and rock masses and improve the safety and efficiency of the mining process, it is necessary to develop an experimental system with independent functional modules that can truly simulate the entire process of deep coal and rock excavation. Summary of the Invention

[0006] The purpose of the present invention is to provide a deep coal rock dynamic disaster servo continuous variable stiffness loading experimental system to solve the problem that existing experimental equipment is difficult to simultaneously achieve servo and continuously variable stiffness loading to truly simulate coal rock dynamic disasters.

[0007] The technical solution of the present invention to solve the above technical problems is as follows:

[0008] A deep coal rock dynamic disaster servo continuous variable stiffness loading experimental system is characterized by comprising: an electro-hydraulic servo rock mechanics experimental system, a variable stiffness loader, a monitoring system, and an electronic control system. The bottom of the electro-hydraulic servo rock mechanics experimental system is connected to the variable stiffness loader, a rock sample is set at the bottom of the variable stiffness loader, and a pad is provided at the bottom of the rock sample.

[0009] The electro-hydraulic servo rock mechanics experimental system is used for external load power source and adopts servo loading mechanism, which has infinite stiffness and will not affect the failure characteristics of coal and rock mass;

[0010] The variable stiffness loader includes a loading rod connected to the electro-hydraulic servo rock mechanics experimental system and a load-bearing platform arranged at the bottom of the loading rod, and an electromagnetic spring assembly is arranged between the loading rod and the load-bearing platform;

[0011] The stiffness of the variable stiffness loader represents the stiffness of the coal-rock mass loading system. It is connected to the electronic control system. Based on the relationship between the stress concentration of the coal-rock mass caused by deep coal mining or excavation activities and the stiffness of the loading system, the electronic control system changes the magnitude and direction of the current in the conductive coil of the variable stiffness loader, thereby adaptively and continuously changing the stiffness of the loading system.

[0012] The monitoring system includes acoustic emission probes and high-speed cameras. Multiple acoustic emission probes are fixed on the surface of the rock sample. A liftable bracket is provided on the side of the rock sample, and a high-speed camera is installed on the liftable bracket. The high-speed camera, liftable bracket, electro-hydraulic servo rock mechanics experimental system, variable stiffness loader and acoustic emission probes are all communicated with the electronic control system.

[0013] The rock mechanics experimental system uses a servo-controlled loading method to apply external loads, which sequentially connects a variable stiffness loader, a rock sample, and a pad. The variable stiffness loader includes a loading rod and a load-bearing platform, with an electromagnetic spring assembly installed between the loading rod and the load-bearing platform, including a high-strength magnet, a spring, a low-magnetic permeability sleeve, and a coil. The monitoring system includes multiple acoustic emission probes fixed to the surface of the rock sample and a high-speed camera installed on a liftable bracket on the side of the sample, which is used to monitor the entire process of coal rock dynamic disaster incubation and occurrence in real time. The electronic control system consists of electronic components and a program control system. It can program the magnitude and direction of the current in the electromagnetic variable stiffness loader according to the functional relationship between the loading state and the local stiffness of the surrounding rock, realizing continuous and automatic changes in the stiffness of the coal rock loading system. This overcomes the shortcomings of traditional experimental equipment that manually control the stiffness of the loading system and thus miss the optimal variable stiffness loading opportunity.

[0014] High-speed cameras and acoustic emission cameras, used as a physical and mechanical information monitoring system, can capture the entire process of coal and rock mass dynamic disaster development from multiple angles in real time. The electronic control system then adjusts the current magnitude and direction of the variable stiffness system's energized coils based on the relationship between loading and stiffness, thereby achieving adaptive variable stiffness loading. Equipped with a physical and mechanical information monitoring system that includes stress, strain, displacement, acoustic emission, and microseismic information, the entire process of coal and rock mass dynamic disaster development can be captured from multiple angles in real time to adjust stiffness.

[0015] Preferably, the electromagnetic spring assembly includes a low magnetic permeability sleeve, which is clamped in the load-bearing platform groove at the top of the load-bearing platform. The loading rod passes through the low magnetic permeability sleeve and acts on the load-bearing platform. A wire is sheathed on the outside of the low magnetic permeability sleeve.

[0016] Preferably, a lower magnet mounted on the top of the load-bearing platform is provided inside the conductor, and an elastic member and an upper magnet are sequentially provided on the top of the lower magnet; the load-bearing platform is installed between the upper magnet and the loading rod.

[0017] Preferably, a load-bearing platform is installed between the upper magnet and the loading rod.

[0018] Preferably, the electro-hydraulic servo rock mechanics experimental system includes a power system, a measurement system, a power control system, a testing machine frame and a protective net.

[0019] Preferably, the power system includes a loading cylinder, which is connected to a pressure push head, and the pressure push head applies pressure to the loading rod; a servo valve is provided on the loading cylinder.

[0020] Preferably, the measurement system includes a load sensor arranged at the bottom of the loading rod and a displacement sensor arranged on the side of the rock sample.

[0021] Preferably, the power control system includes a controller and a software system.

[0022] Preferably, an operating platform is provided at the bottom of the variable stiffness loader, and a test switch is provided at the side end of the operating platform.

[0023] The present invention has the following beneficial effects:

[0024] Improved experimental flexibility and accuracy: The system can automatically and continuously vary the stiffness of the loading system by adjusting the current flow (waveform, magnitude, and direction) in the energized coil. This design significantly enhances experimental flexibility, allowing researchers to easily adjust experimental conditions based on their needs. Furthermore, because the system precisely controls the loading process, it ensures the accuracy and reliability of experimental results, providing strong support for in-depth research into the mechanisms of dynamic disasters in coal and rock masses.

[0025] Comprehensive multi-angle monitoring: The system integrates multiple monitoring methods, including stress, strain, displacement, acoustic emission, and high-speed video, enabling real-time, multi-angle monitoring and observation of the development and occurrence of coal and rock dynamic disasters. This comprehensive monitoring approach helps reveal the mechanical behavior and failure modes of coal and rock masses, providing a scientific basis for assessing disaster risks and formulating disaster prevention measures.

[0026] Simulating realistic stress paths and stiffness environments: The system automatically and continuously adjusts its stiffness based on the degree of stress concentration (loading) experienced by coal and rock masses during deep mining or underground excavation. This design enables the system to realistically simulate the stress paths and stiffness environments experienced by various types of dynamic disasters, such as rock bursts, rockbursts, and mining tremors, occurring in deep coal and rock masses. This provides an important tool for uncovering the mechanisms of these disasters.

[0027] Enhanced universality of the experimental device: Through the adaptive continuously variable stiffness system, the experimental device can automatically adjust its stiffness according to the external loading state and the changes in the local stiffness of the surrounding rock, without the need for manual judgment of the loading state; this automated adjustment mechanism enhances the universality of the experimental device, making it applicable to different types of coal rock dynamic disaster research.

[0028] Promoting Scientific Research and Engineering Applications: The successful development of this experimental system not only provides strong experimental equipment support for scientific research but is also expected to promote the advancement and development of related engineering technologies. For example, in areas such as mining and underground space utilization, the system is expected to provide important technical support and solutions for disaster prevention, mitigation, and safety assurance. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the structure of the deep coal and rock mass dynamic disaster servo continuous variable stiffness loading experimental system of the present invention;

[0030] Figure 2 This is a schematic diagram of the structure of the variable stiffness loader of the deep coal and rock mass dynamic disaster servo continuous variable stiffness loading experimental system of the present invention;

[0031] Figure 3 This is a schematic diagram of the internal structure of the variable stiffness loader of the deep coal and rock mass dynamic disaster servo continuous variable stiffness loading experimental system of the present invention;

[0032] Figure 4 This is a schematic diagram of the acoustic emission probe structure of the deep coal and rock mass dynamic disaster servo continuous variable stiffness loading experimental system of the present invention;

[0033] Figures 1 to 4The reference numerals shown in the figure respectively represent: high-speed camera 1, liftable bracket 2, electro-hydraulic servo rock mechanics experimental system 3, loading cylinder 31, pressure push head 32, test switch 33, electronic control system 4, operating table 5, variable stiffness loader 6, loading rod 61, upper magnet 610, lower magnet 611, low magnetic permeability sleeve 612, wire 62, load-bearing platform 63, elastic member 64, nut 65, groove 66, load-bearing platform groove 67, load-bearing platform 69, rock sample 7, pad 8, acoustic emission probe 9. DETAILED DESCRIPTION

[0034] The following is a clear and complete description of the technical solution of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0035] Please refer to Figure 1-4 This embodiment provides a servo-controlled continuous variable stiffness loading experimental system for deep coal and rock mass dynamic hazards. This system is designed to simulate the changes in stress and surrounding rock stiffness during deep coal and rock mass excavation, thereby further studying the mechanisms of coal and rock mass dynamic hazards. The following is a detailed description of this experimental system.

[0036] The experimental system primarily consists of an operating table 5 and an electro-hydraulic servo rock mechanics experimental system 3. The operating table 5 serves as the supporting platform for the entire experimental system, with the electro-hydraulic servo rock mechanics experimental system 3 installed on top. The electro-hydraulic servo rock mechanics experimental system 3 is the core device for applying external loads and comprises key components such as a power system, a measurement system, a power control system, a testing machine frame, and a protective net. The power system includes a loading cylinder 31, which, through a connection to a pressure pusher 32, applies pressure to a loading rod 61 to load the rock specimen 7. To ensure loading accuracy and stability, a servo valve is installed on the loading cylinder 31 to precisely control the pressure pusher 32. The measurement system includes a load sensor located at the bottom of the loading rod 61 and a displacement sensor located to the side of the rock specimen 7. These sensors monitor load and displacement changes in real time during the loading process, providing an important basis for collecting and analyzing experimental data. The power control system includes a controller and a software system, which work together to achieve precise control of the entire experimental system and data acquisition. The testing machine frame provides a stable support structure for the entire experimental system, while the protective net is used to protect the safety of experimental personnel and equipment.

[0037] A variable stiffness loader 6 is connected to the bottom of the electro-hydraulic servo rock mechanics experimental system 3. A key component of the experimental system, variable stiffness loader 6 enables continuous variation in loading stiffness, thereby simulating the changing stiffness environment of deep coal and rock masses during excavation. The variable stiffness loader 6 comprises a loading rod 61 and a load-bearing platform 63, with an electromagnetic spring assembly positioned between them. The electromagnetic spring assembly includes a wire 62 sleeved around the loading rod 61. A low-permeability sleeve 612 is positioned within the wire 62, which is locked within a load-bearing platform groove 67 at the top of the load-bearing platform 63. The loading rod 61 passes through the low-permeability sleeve 612 and acts on the load-bearing platform 69, ensuring stable current flow in the wire 62 while preventing current from interfering with the loading rod 61 and other components. A lower magnet 611 is positioned within the wire 62, with an elastic member 64 and an upper magnet 610 positioned on top of the lower magnet 611. The upper magnet 610 and the lower magnet 611 are connected by an elastic member 64, which can be a spring or other elastic component to form an electromagnetic spring assembly. When current flows through the wire 62, a magnetic force is generated between the upper magnet 610 and the lower magnet 611. This magnetic force, combined with the elastic force of the elastic member 64, adjusts the stiffness of the loading rod 61.

[0038] To further enhance the stability and load-bearing capacity of the variable-stiffness loader 6, a load-bearing platform 69 is installed between the upper magnet 610 and the loading rod 61. The load-bearing platform 69 can distribute the load borne by the loading rod 61, thereby extending the service life of the loading rod 61 and improving the stability of the entire experimental system.

[0039] A pad 8 is placed at the bottom of the rock sample 7. Multiple acoustic emission probes 9 are fixed to the surface of the rock sample 7. These probes can monitor the internal crack activity and failure characteristics of the rock sample 7 in real time during loading. The other side of the acoustic emission probes 9 is connected to the electronic control system 4, which transmits the monitoring data in real time to a computer for analysis.

[0040] To record the failure process of rock specimen 7, the experimental system also features a liftable support 2 and a high-speed camera 1. The liftable support 2 can be adjusted in height according to experimental requirements, allowing the high-speed camera 1 to be positioned appropriately on the lift platform of the liftable support 2. By adjusting the height and angle of the lift platform, the high-speed camera 1 can directly face the rock specimen 7, capturing detailed data on rock deformation and failure. The high-speed camera 1, liftable support 2, electro-hydraulic servo rock mechanics experimental system 3, variable stiffness loader 6, and acoustic emission probe 9 are all connected to an electronic control system 4, enabling real-time data transmission and sharing.

[0041] Before the experiment begins, a comprehensive inspection of the experimental system is required. First, check the equipment for oil and air leaks and ensure that all connections are secure. Next, perform a safety check to ensure that all safety devices, including emergency stop buttons and limit switches, are in working order. Furthermore, verify that all remote control valves remain open. This ensures that the system can automatically respond and protect the safety of both personnel and equipment in the event of an unexpected power, gas, or oil outage.

[0042] After completing the inspection, start assembling the variable stiffness loader 6. First, fix the lower magnet 611 with five nuts 65, which are located at the four corners and the middle of the magnet. At the same time, connect austenitic stainless steel high-strength springs at corresponding positions. These springs are arranged in the middle of the circular groove 68 of the magnet on the lower magnet 611. Place the lower magnet 611 in the middle of the groove 66 on the load-bearing platform 63 and tightly connect it to the load-bearing platform 63 using the other side of the nut 65. Next, for the upper magnet 610 of the same size as the lower magnet 611, similarly connect five high-strength springs in the circular groove 68 of the magnet and fix them with nuts 65 at the four corners and the middle of the upper magnet 610. Then, place the load-bearing platform 69, which is slightly smaller than the upper magnet 610, in the middle of the upper magnet and connect it at the midpoints of the four sides of the load-bearing platform through nuts 65. At the same time, weld the loading rod 61 and the load-bearing platform 69 together to form a complete loading structure. Finally, cover the low permeability sleeve 612, ensuring that it fits into the bearing platform groove 67, and wind the wire 62 along the low permeability sleeve 612. Connect the other end of the wire 62 to the electronic control system 4 to complete the overall assembly of the variable stiffness loader 6.

[0043] Place the assembled variable-stiffness loader 6 on the loading platform of the electro-hydraulic servo rock mechanics experimental system 3. Secure a ring of acoustic emission probes 9 to the rock sample 7, and connect the other side of the acoustic emission probes to the electronic control system 4. Next, place the rock sample 7 directly below the variable-stiffness loader 6, with a spacer 8 underneath. Adjust the adjustable high-speed camera bracket 2 to the appropriate distance and secure the high-speed camera 1 to the bracket's lifting platform. By adjusting the height and angle of the lifting platform, the high-speed camera 1 is positioned directly above the rock sample 7, capturing detailed data on rock deformation and failure.

[0044] With all preparations complete, the experiment began. First, the power system of the electro-hydraulic servo rock mechanics experimental system 3 was activated, applying pressure to the loading rod 61 via the loading cylinder 31 and the pressure pusher 32. During the loading process, the measurement system monitored load and displacement changes in real time and transmitted the data to the electronic control system 4 for analysis. Simultaneously, the acoustic emission probe 9 monitored the crack activity and failure characteristics within the rock specimen 7 in real time and transmitted the data to a computer in real time. A high-speed camera 1 captured the failure images of the rock specimen 7 in real time, providing an important basis for the collection and analysis of experimental data.

[0045] During the experiment, the electronic control system 4 adjusts the current applied to the variable-stiffness loader 6 to alter its stiffness. The electronic control system 4 can set different current waveforms, magnitudes, and directions based on experimental requirements, thereby enabling continuous adjustment of the loading system's stiffness. This design overcomes the limitation of traditional loading equipment, which can only achieve a single, specific stiffness in each experiment, and enables more precise and quantitative analysis of the stress path and energy during the dynamic failure process of coal and rock masses.

[0046] By integrating monitoring equipment such as stress, strain, displacement, acoustic emission, and high-speed cameras, the experiment was able to capture key physical and mechanical information about the coal and rock mass during loading in real time. Stress monitoring equipment records stress changes in the coal and rock mass in real time, revealing its mechanical behavior and failure mode. Strain data reflects the degree of deformation and reveals its elastic and plastic deformation characteristics. Displacement monitoring equipment records displacement changes in the coal and rock mass, analyzing its stability and predicting failure locations. Acoustic emission technology captures the formation and expansion of internal microcracks, monitors crack activity, assesses failure characteristics, and provides real-time warnings. High-speed cameras record the dynamic process of rock failure, including the formation and expansion of cracks and the ejection of coal and rock fragments during dynamic disasters such as rock bursts.

[0047] The core advantage of this experimental system lies in its ability to automatically and continuously vary the stiffness of the loading system by adjusting the current flow (waveform, magnitude, and direction) in the energized coil. This design not only enhances experimental flexibility but also simplifies the system structure, providing an efficient and precise solution for variable stiffness requirements in engineering applications. Furthermore, by constructing a physical and mechanical information monitoring system that integrates stress, strain, displacement, acoustic emission, and high-speed video monitoring, it enables real-time, multi-angle, and comprehensive monitoring and observation of the incubation and occurrence of coal and rock mass dynamic hazards, providing scientific data for revealing the mechanisms of different types of deep coal and rock mass dynamic hazards.

[0048] Furthermore, the system automatically and continuously adjusts the stiffness of the loading system (and surrounding rock) based on the correlation between the external loading state and changes in the local stiffness of the surrounding rock. Specifically, excavation operations lead to stress concentration and a decrease in surrounding rock stiffness. Based on the functional relationship between the stress state (degree of concentration) of coal and rock masses and the stiffness of the surrounding rock, this system, through programmed control of the current flow in the energized coil, implements this functional relationship in physical experiments, thereby achieving the adaptive and continuously variable stiffness function of the loading system. This system thus eliminates the need for manual judgment of the loading state to determine when to adjust stiffness, thus overcoming the shortcomings of existing technologies.

[0049] This experimental system can automatically and continuously adjust the system stiffness according to the degree of stress concentration (loading) in the coal and rock mass during deep mining or underground space excavation, thereby realistically simulating the stress path and stiffness environment experienced by different types of dynamic disasters such as rock burst, rock burst, and mining tremors in deep coal and rock masses. This technology breaks through the limitations of traditional devices that require manual judgment of loading status and the timing of stiffness changes, and achieves accurate simulation of the incubation and occurrence process of different types of coal and rock dynamic disasters, making the developed experimental device more universal. Through the above-mentioned adaptive continuously variable stiffness system, different types of dynamic disasters in deep coal and rock masses can be more accurately reproduced under controllable laboratory variable conditions, providing strong experimental equipment support for studying the mechanism of dynamic disasters in deep coal and rock masses.

[0050] To sum up, the deep coal and rock dynamic disaster servo continuous variable stiffness loading experimental system provided in this embodiment realizes real-time, multi-angle comprehensive monitoring and observation of the incubation and occurrence process of deep coal and rock dynamic disasters by adopting key components and monitoring equipment such as electro-hydraulic servo rock mechanics experimental system, variable stiffness loader, acoustic emission probe, high-speed camera, etc.

[0051] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A deep coal rock mass dynamic disaster servo continuous variable stiffness loading experimental system, characterized by: include: An electro-hydraulic servo rock mechanics experimental system (3), a variable stiffness loader (6), a monitoring system, and an electronic control system (4), wherein the bottom of the electro-hydraulic servo rock mechanics experimental system (3) is connected to the variable stiffness loader (6), a rock sample (7) is provided at the bottom of the variable stiffness loader (6), and a pad (8) is provided at the bottom of the rock sample (7); the electro-hydraulic servo rock mechanics experimental system (3) is used for an external load power source; The variable stiffness loader (6) comprises a loading rod (61) connected to the electro-hydraulic servo rock mechanics experimental system (3) and a load-bearing platform (63) arranged at the bottom of the loading rod (61), and an electromagnetic spring assembly is provided between the loading rod (61) and the load-bearing platform (63); The variable stiffness loader (6) is connected to the electronic control system (4), and the electronic control system (4) changes the magnitude and direction of the current in the conductive coil of the variable stiffness loader (6), thereby adaptively and continuously changing the stiffness of the loading system; The monitoring system comprises an acoustic emission probe (9) and a high-speed camera (1); a plurality of the acoustic emission probes (9) are fixed on the surface of the rock sample (7); a liftable bracket (2) is provided on the side of the rock sample (7); the high-speed camera (1) is provided on the liftable bracket (2); the high-speed camera (1), the liftable bracket (2), the electro-hydraulic servo rock mechanics experimental system (3), the variable stiffness loader (6) and the acoustic emission probe (9) are all connected to the electronic control system (4); The electromagnetic spring assembly includes a low-permeability sleeve (612), the low-permeability sleeve (612) is clamped in a load-bearing platform groove (67) at the top of the load-bearing platform (63), the loading rod (61) passes through the low-permeability sleeve (612) and acts on the load-bearing platform (69), and the low-permeability sleeve (612) is externally sleeved with a wire (62); A lower magnet (611) mounted on the top of the load-bearing platform (63) is provided inside the wire (62), and an elastic member (64) and an upper magnet (610) are sequentially provided on the top of the lower magnet (611); the load-bearing platform (69) is installed between the upper magnet (610) and the loading rod (61).

2. The deep coal and rock mass dynamic disaster servo continuous variable stiffness loading experimental system according to claim 1 is characterized in that: The electro-hydraulic servo rock mechanics experimental system (3) comprises a power system, a measurement system, a power control system, a testing machine frame and a protective net.

3. The deep coal and rock mass dynamic disaster servo continuous variable stiffness loading experimental system according to claim 2 is characterized in that: The power system comprises a loading oil cylinder (31), the loading oil cylinder (31) is connected to a pressure push head (32), and the pressure push head (32) applies pressure to the loading rod (61); a servo valve is provided on the loading oil cylinder (31).

4. The deep coal and rock mass dynamic disaster servo continuous variable stiffness loading experimental system according to claim 2 is characterized in that: The measurement system comprises a load sensor arranged at the bottom of the loading rod (61) and a displacement sensor arranged on the side of the rock sample (7).

5. The deep coal and rock mass dynamic disaster servo continuous variable stiffness loading experimental system according to claim 2 is characterized in that: The power control system includes a controller and a software system.

6. The deep coal and rock mass dynamic disaster servo continuous variable stiffness loading experimental system according to claim 1 is characterized in that: An operating platform (5) is provided at the bottom of the variable stiffness loader (6), and a test switch (33) is provided at the side end of the operating platform (5).

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