Dynamic triaxial testing apparatus

Abstract

The application discloses a dynamic-static separation type experimental device for measuring triaxial dynamic mechanical properties of rock, wherein a dynamic Hopkinson pressure bar module and a static triaxial loading module form a dynamic-static separation loading structure; a first piston and a second piston are respectively arranged separately from a first loading oil cylinder and a second loading oil cylinder, and are directly in contact with two ends of a sample and not directly in contact with a pressure chamber; an incident bar and a transmission bar are respectively in contact with outer end faces of the first piston and the second piston but are not connected; static axial pressure is provided by the first loading oil cylinder and the second loading oil cylinder, dynamic balance of the first piston and the second piston is realized through parallel pipelines of the first loading oil cylinder and the second loading oil cylinder, and the static axial pressure is not transmitted through the incident bar or the transmission bar; a dynamic shock wave is transmitted from the incident bar to the transmission bar through the first piston, the sample and the second piston, and is not transmitted through the oil cylinder structure. The device realizes strict physical path separation of static load and dynamic load, and can support long-term creep and relaxation experiments after impact disturbance.

Description

Technical Field

[0001] This application belongs to the field of rock dynamics testing, specifically relating to a dynamic-static separation experimental device for measuring the triaxial dynamic mechanical properties of rocks. Background Technology

[0002] Deep rock masses exist in a high-stress environment and exhibit unique dynamic-static combined loading mechanical responses under dynamic disturbances such as blasting excavation, TBM rock breaking, and seismic wave propagation. Their failure mechanisms differ significantly from those of shallow rock masses. Therefore, experimental devices capable of simulating dynamic impact disturbances under high-stress conditions have become crucial tools for deep rock mechanics research. To address this need, a dynamic-static combined triaxial Hopkinson bar experimental system has been designed, attempting to integrate the static triaxial loading module with the dynamic SHPB module. However, the following shortcomings remain: 1) Severe dynamic-static coupling interference, making it impossible to maintain axial static pressure after impact: Existing devices typically apply static axial pressure directly to the Hopkinson bar, causing the dynamic shock wave to superimpose with the static load as it propagates along the bar. At the moment of impact, the static load sensor signal saturates and distorts, making servo control impossible. After the impact, the static pressure system depressurizes to zero within milliseconds, making it impossible to conduct long-term creep or relaxation experiments on a timescale ranging from hours to months after the impact disturbance. This means that current technology can only acquire data at the instant of impact, making it difficult to study the time-dependent evolution of deep surrounding rock after disturbance, which is seriously inconsistent with actual engineering conditions.

[0003] 2) Dynamic loads cause large confining pressure fluctuations, making boundary conditions difficult to control: During dynamic impact, the specimen expands in volume due to the Poisson effect, rapidly compressing the hydraulic oil within the confining pressure chamber. Because hydraulic oil has a high bulk modulus, even small volume changes can cause significant confining pressure fluctuations. Traditional devices exhibit large confining pressure fluctuations, easily causing experimental boundary conditions to deviate from preset values, leading to the failure of dynamic stress balance criteria and unreliable experimental data. Existing device designs often rely on empirical trial-and-error, lacking confining pressure fluctuation prediction models based on oil compressibility and specimen volume deformation, and also lacking servo compensation algorithms coupled with hardware structure. This results in blind confining pressure control, making it difficult to perform parametric design for different lithologies and impact intensities.

[0004] 3) Mismatched measurement systems and incoordination of static and dynamic data: The sampling rate of static deformation measurement sensors is typically only 1-10 kHz, making it difficult to capture microsecond-level dynamic strain; while dynamic strain gauges, although capable of capturing high-frequency signals, cannot operate stably in long-term aging experiments. Existing technologies lack effective dual-sampling-rate data fusion methods, resulting in the inability to accurately reconstruct complete stress-strain-time curves under combined static and dynamic loading. Summary of the Invention

[0005] The purpose of this application is to provide a dynamic-static separation experimental device for measuring the triaxial dynamic mechanical properties of rocks. It adopts a dynamic-static separation loading structure to achieve strict physical path separation between static and dynamic loads, and can support long-term creep and relaxation experiments after impact disturbance.

[0006] The technical solution adopted in this application is: A dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks includes: Dynamic Hopkinson bar module for generating and measuring dynamic shock waves, including incident and transmission bars and strain gauges on the bars; A static triaxial loading module for applying static axial pressure includes a first loading cylinder and its first piston, a second loading cylinder and its second piston, a pressure chamber, and a load-bearing frame. The dynamic Hopkinson pressure bar module and the static triaxial loading module form a dynamic-static separation loading structure: the first piston and the second piston are separately set from the first loading cylinder and the second loading cylinder, respectively, and are in direct contact with both ends of the sample but not in direct contact with the pressure chamber; the incident rod and the transmission rod are in contact with the outer end faces of the first piston and the second piston, respectively, but are not connected; the static axial pressure is provided by the first loading cylinder and the second loading cylinder, and the dynamic balance of the first piston and the second piston is achieved through the parallel pipeline of the first loading cylinder and the second loading cylinder, without being transmitted through the incident rod or the transmission rod; the dynamic shock wave is transmitted from the incident rod through the first piston, the sample, and the second piston to the transmission rod, without being transmitted through the cylinder structure; Also includes: A high-frequency servo confining pressure stabilization module is used to suppress confining pressure fluctuations caused by dynamic impacts, including the confining pressure chamber and its servo valve and controller; The dual sampling rate data acquisition and fusion module is used to simultaneously acquire static and dynamic data and fuse the two sets of data to obtain a complete dynamic-static combined full stress-strain curve.

[0007] Preferably, the dynamic-static separation loading structure adopts asymmetric axial pressure compensation control: the first loading cylinder adopts a large buffer chamber with fixed volume as a passive support end; the second loading cylinder adopts active control with a high-frequency servo valve as a dynamic compensation end; during dynamic impact, the first piston moves backward under the impact force of the incident rod, the volume of the large buffer chamber of the first loading cylinder increases and the pressure drops instantaneously, and the high-frequency servo valve of the second loading cylinder detects the pressure change and quickly releases pressure to compensate, so that the total axial pressure fluctuation is controlled within five percent of the set value.

[0008] Preferably, the large buffer chamber of the first loading cylinder is filled with hydraulic oil and compressible nitrogen, and the chamber of the second loading cylinder is filled with hydraulic oil.

[0009] Preferably, the volume of the confining pressure cavity ;in: The bulk elastic modulus of the hydraulic oil within the confining pressure cavity; For the volume change of the sample, we have , The initial volume of the sample. For the volumetric strain of the sample, we have , This represents the axial strain increment of the specimen. Let be the radial strain increment of the specimen, and , The Poisson's ratio of the sample; Set the initial confining pressure value.

[0010] Preferably, the high-frequency servo confining pressure stabilization module adopts a high-frequency servo pressure relief control strategy: when an increase in confining pressure is detected, the controller drives the servo valve to quickly open the oil drain channel and release the pressure. Oil, making Discharge speed satisfy: ,in for The discharge speed at all times, For flow coefficient, for The opening area of ​​the servo valve at any given time. for Constant pressure, For return oil pressure, The density of the hydraulic oil in the confining pressure chamber.

[0011] Preferably, the high-frequency servo confining pressure stabilization module adopts a shock wave synchronous trigger-prediction-compensation timing control strategy: the incident wave signal is monitored in real time by strain gauges on the incident rod; when the strain gauges detect that the incident wave amplitude exceeds a set threshold, the signal is used as a trigger source to advance the response. Time sends feedforward compensation commands to the controller, where, The distance from the strain gauge to the first piston. To determine the elastic wave velocity in the incident rod, the controller pre-adjusts the opening area of ​​the servo valve before the shock wave reaches the first piston, so that the axial pressure is already in a pre-compensated state at the moment of impact.

[0012] Preferably, the dual-sampling-rate data acquisition and fusion module includes a hardware synchronization triggering unit, a static acquisition channel operating at a first sampling rate, a dynamic acquisition channel operating at a second sampling rate, and a data fusion processor. The hardware synchronization triggering unit generates a synchronization trigger signal based on the same physical event, simultaneously activating the static acquisition channel and the dynamic acquisition channel to achieve microsecond-level time synchronization. The data fusion processor is used to perform time alignment, vibration decoupling, stress correction, and cross-channel splicing of the two sets of data to reconstruct a complete dynamic-static combined full stress-strain curve.

[0013] Preferably, the hardware synchronization triggering unit includes a trigger strain gauge, a threshold discrimination circuit, and a TTL pulse generator attached to the incident rod. The trigger strain gauge is connected to the first channel of the ultra-dynamic strain gauge. When the bullet impacts the incident rod, the trigger strain gauge detects the incident wave signal. After passing through the threshold discrimination circuit, the TTL pulse generator generates a TTL rising edge pulse signal and simultaneously outputs it to the external trigger port of the ultra-dynamic strain gauge. This activates the dynamic acquisition channel for high-speed acquisition at a sampling rate of 10 MHz and activates the static acquisition channel for data stream interruption marking at a sampling rate of 10 kHz. The static acquisition channel and the dynamic acquisition channel are synchronously activated by the same TTL rising edge, achieving a time synchronization accuracy of ±1 μs.

[0014] Preferably, the data fusion processor includes: Time alignment unit, used to align all data based on absolute time; An adaptive filtering unit is used to filter the measured signal from the static acquisition channel to separate the actual sample deformation and vibration noise. The dynamic-static deformation decoupling unit is used to remove inertial displacement from the measured signal to obtain the true dynamic deformation of the sample; Circumferential deformation indirect measurement unit, used to indirectly measure the circumferential deformation of the specimen; The triaxial static load correction unit is used to correct dynamic stress so that the absolute reference of the dynamic stress curve is consistent with the static load system. The data stitching unit is used to stitch together the pre-impact static segment, the dynamic segment during impact, the transition fusion segment, and the post-impact static segment to form a complete stress-strain curve.

[0015] Preferably, the working principle of the time alignment unit is as follows: the physical time when the stress wave arrives at the end face of the sample is taken as the physical time zero point of the dynamic channel. , , This refers to the time when the TTL trigger pulse is emitted. Let be the propagation time of the stress wave from the trigger point to the end face of the specimen. , The distance from the strain gauge on the incident rod to the first piston is denoted as . The elastic wave velocity in the incident rod; dynamic data is... As an absolute time reference, pre-calibration determines the relative time difference of the static channel. Static channel data overall translation Back alignment.

[0016] Preferably, the adaptive filtering unit works by using a 4th-order Butterworth low-pass filter, whose frequency response function is: The filter order n=4, and the cutoff frequency is automatically adjusted according to the reflected wave energy. ,in The initial cutoff frequency, The adjusted cutoff frequency. For adaptive coefficients, For the energy of the reflected wave, This represents the maximum reflected wave energy.

[0017] Preferably, the working principle of the dynamic-static deformation decoupling unit is as follows: the strain gauge channel synchronously acquires reflected wave signals. Through reflected wave signals Estimate the inertial displacement of the incident rod ,in, The transfer coefficient between the frame and the incident rod was determined through calibration tests. The distance from the strain gauge to the first piston. The elastic wave velocity in the incident rod; from the measured signal Remove the inertial displacement of the incident rod The dynamic deformation of the actual sample was obtained: .

[0018] Preferably, the working principle of the circumferential deformation indirect measurement unit is: based on the indirect measurement method of volume conservation, the axial deformation of the sample is measured in real time. Changes in the volume of oil in the confining pressure chamber According to the volume conservation equation Reverse calculation of radial deformation of the specimen Thus, the circumferential strain is obtained. ,in, This represents the volume change of the sample. The diameter of the sample is 1. This represents the height of the sample.

[0019] Preferably, the working principle of the triaxial static load correction element is: using the triaxial corrected dynamic stress formula. ,in The steady-state static load before impact is determined by the average value of the pre-impact in the static channel. For the dynamic stress calculated by the SHPB three-wave method, To compensate for fluctuations under static load servo conditions, data is recorded from a static channel at a sampling rate of 10 kHz, upsampled to a 10 MHz time axis through cubic spline interpolation, and then superimposed point-to-point with the dynamic data.

[0020] Preferably, the working principle of the data splicing unit is as follows: Define transition time window ,in The end time of the dynamic process. This is the moment when the static vibration has completely decayed. Transitional fusion stress for: , in, The weighting coefficients for dynamic data adopt an exponential decay form. , The transition time constant; The dynamic stress calculated using the SHPB three-wave method; The filtered static stress; Permanent deformation caused by impact for:

[0021] in, This represents the average strain during the statically stable phase after the impact. This is the static stability period following the impact; This represents the average strain during the statically stable phase before impact. This is the static and stable period before the impact; The complete strain data after the impact is stitched together as follows:

[0022] in, For the complete strain sequence of the specimen, Strain measured in a static channel. This represents the static stability strain value before impact. For dynamic strain increments, To facilitate integration and adaptation during the transition period; The complete stress splicing is as follows:

[0023] in, For a complete stress sequence of the specimen, Stress measured in the static channel. This represents the filtered static stress.

[0024] Preferably, the data fusion processor further includes a consistency verification unit, which employs a multi-channel cross-validation mechanism to verify the reliability of the data fusion. Under static steady state, axial compression Confining pressure Axial deformation of the specimen and radial deformation The consistency constraints of the rock mechanics constitutive relation should be satisfied: , , ,

[0025] in, For axial stress, The cross-sectional area of ​​the sample. For confining pressure stress, For axial strain, The initial height of the sample. For radial strain, The initial diameter of the sample; For the linear elastic stage, the generalized Hooke's law should be satisfied: ,

[0026] in, The elastic modulus of the rock. The Poisson's ratio of the rock; The system calculates the residuals in real time: ,

[0027] in, For axial strain consistency residuals, For radial strain consistency residuals; If the residual exceeds the set threshold, it is determined that there is drift or poor contact in a certain channel. The system will automatically mark the data for that period and prompt for recalibration.

[0028] The beneficial effects of this application are: This application employs a dynamic-static separation loading structure. The SHPB rod only contacts the outer end face of the piston and does not bear static load. The SHPB rod only transmits dynamic impact force, while the axial static load is directly applied in balance through the first and second pistons. Dynamic and static loads do not interfere with each other, achieving strict physical path separation between them. The static load sensor always measures only static force and is unaffected by dynamic wave interference. After the impact, the hydraulic cylinder servo system can continue to maintain pressure, and the static load will not be released. This allows for creep and relaxation experiments lasting from seven days to six months after the impact disturbance. This application adds a high-frequency servo confining pressure stabilization module and a dual-sampling-rate data acquisition and fusion module, which can suppress confining pressure fluctuations caused by dynamic impacts and obtain complete dynamic-static combined stress-strain curves.

[0029] This device adopts asymmetric axial pressure compensation control, which simplifies the traditional dual control and dual compensation to single-end active compensation, reducing the number of servo control ports by half, reducing system complexity and cost, while improving response speed, ensuring axial pressure stability during impact, and providing accurate initial conditions for subsequent long-term tests.

[0030] The quantitative design of the confining pressure cavity volume changes the traditional reliance on trial and error, ensuring that the confining pressure fluctuation is always controlled within 5% of the set value.

[0031] By actively relieving pressure and compensating for excess oil caused by dynamic impact, the dynamic stability of the confining pressure is rapidly released, further improving the dynamic stability of the confining pressure and ensuring that the dynamic stress balance criterion is effectively established.

[0032] This device adopts a shock wave synchronous trigger-prediction-compensation timing control strategy. This "predictive" control strategy shortens the compensation response time from the traditional "detection delay + valve delay" to only the valve mechanical delay, thus improving the real-time performance of axial pressure maintenance.

[0033] Hardware synchronization only solves the problem of simultaneous startup. Setting up a time alignment unit allows the zero-point time of dynamic and static data to be aligned based on the physical laws of stress wave propagation. During impact, the measured signal from the static acquisition channel is composed of the superposition of actual sample deformation and vibration noise; an adaptive filtering unit is set up to eliminate vibration noise. During dynamic impact, the superposition of actual sample deformation and the inertial displacement of the incident rod caused by the shock wave makes it impossible to directly read the sample deformation; a dynamic-static deformation decoupling unit is set up to eliminate the inertial displacement of the incident rod, ensuring the accuracy of dynamic deformation data. Due to chamber space limitations and high-pressure sealing requirements, it is difficult to directly place circumferential strain gauges on the sample surface; an indirect circumferential deformation measurement unit is set up to indirectly measure the circumferential deformation of the sample. Traditional SHPB... The two-wave / three-wave method assumes that the specimen has no initial static load. However, in reality, the specimen is subjected to a triaxial static load. The stress wave generated by the dynamic impact is a transient increment superimposed on the static load. More importantly, the static load servo system is compensating at the moment of impact, and the static load itself has a slight fluctuation. This fluctuation is not negligible on the dynamic time scale (microsecond level) and must be accurately separated from the dynamic stress. Setting up a triaxial static load correction unit can ensure that the absolute reference of the dynamic stress curve is consistent with the static load system, avoiding the error of the traditional assumption that the dynamic stress starts from zero. The data stitching unit realizes seamless stitching of the static segment before impact, the dynamic segment during impact, the transition fusion segment, and the static segment after impact. For the first time, a complete stress-strain curve covering the evolution from microsecond-level dynamic response to day-month-level aging is obtained.

[0034] The consistency verification unit ensures the physical consistency between the 10 kHz and 10 MHz data sets, ensuring that the fused data conforms to the consistency constraints of rock mechanics constitutive relations, effectively preventing fusion errors caused by sensor failures, and greatly improving the reliability of experimental data. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the dynamic-static separation experimental device for measuring the triaxial dynamic mechanical properties of rocks in this application.

[0036] Figure 2 for Figure 1 Cross-sectional view at point AA.

[0037] Figure 3This is a flowchart illustrating the main working process of the static-dynamic separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks in this application.

[0038] In the figure: 1-Incident rod; 2-First loading cylinder; 3-Parallel pipeline; 4-Pressure chamber; 5-Second loading cylinder; 6-Transmission rod; 7-Bearing frame; 8-First piston; 9-Second piston; 10-Sample. Detailed Implementation

[0039] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0040] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0041] Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0042] The features and performance of this application will be further described in detail below with reference to the embodiments.

[0043] This application discloses a dynamic-static separation experimental device for measuring the triaxial dynamic mechanical properties of rocks, including a dynamic Hopkinson pressure bar module, a static triaxial loading module, a high-frequency servo confining pressure stabilization module, a dual-sampling-rate data acquisition and fusion module, and a long-term pressure holding and aging experimental module. The dynamic Hopkinson pressure bar module is used to generate and measure dynamic shock waves, including an incident rod 1 and a transmission rod 6, as well as strain gauges on the rods. The static triaxial loading module is used to apply static axial pressure, including a first loading cylinder 2 and its first piston 8, a second loading cylinder 5 and its second piston 9, a pressure chamber 4, and a bearing frame 7 (first...). Loading cylinder 2 and second loading cylinder 5 are fixed on the bearing frame 7); the high-frequency servo confining pressure stabilization module is used to suppress confining pressure fluctuations caused by dynamic impacts, including the confining pressure chamber and its servo valve and controller (the servo valve is used to release pressure from the confining pressure chamber, and the controller is used to control the servo valve); the dual sampling rate data acquisition and fusion module is used to simultaneously acquire static and dynamic data and fuse the two sets of data to obtain a complete dynamic-static combined full stress-strain curve; the long-term pressure holding and aging test module is used to maintain confining pressure and axial pressure for a long period of time (from seven days to six months) after impact disturbance in order to conduct creep and relaxation tests.

[0044] Among them, such as Figure 1 and Figure 2 As shown, the dynamic Hopkinson pressure bar module and the static triaxial loading module form a dynamic-static separation loading structure: the first piston 8 and the second piston 9 are separately set with the first loading cylinder 2 and the second loading cylinder 5, respectively, and are in direct contact with both ends of the sample 10, but not in direct contact with the pressure chamber 4; the incident rod 1 and the transmission rod 6 are in contact with the outer end faces of the first piston 8 and the second piston 9, respectively, but are not connected; the static axial pressure is provided by the first loading cylinder 2 and the second loading cylinder 5, and the dynamic balance of the first piston 8 and the second piston 9 is achieved through the parallel pipeline 3 of the first loading cylinder 2 and the second loading cylinder 5, without passing through the incident rod 1 or the transmission rod 6; the dynamic shock wave is transmitted from the incident rod 1 through the first piston 8, the sample 10, and the second piston 9 to the transmission rod 6, without passing through the cylinder structure; In traditional devices, static load balance can only be achieved by connecting the hydrostatic piston to pressure chamber 4. The static axial pressure is directly applied to the SHPB rod, causing the dynamic shock wave to be transmitted to the cylinder, resulting in the dynamic shock wave and static load being superimposed (assuming the cross-sectional areas of the incident rod 1 and the transmission rod 6 are...). The cross-sectional area of ​​sample 10 is Static axial compression applied to specimen 10 Provided by the stress in the rod: ,because Stress in the rod Directly equal to the stress of the sample, during dynamic impact, the incident wave Superimposed on the static load, the total stress borne by specimen 10 is: , It is a reflected wave. (This refers to the static stress in the rod). This superposition causes the static load sensor to be constantly exposed to dynamic high-frequency signals, resulting in a significant deviation of the measured value from the true static load. Furthermore, the residual stress in the rod decays rapidly after the impact, and the static pressure returns to zero, which can easily lead to stress imbalance and experimental failure.

[0045] This application adopts a dynamic-static separation loading structure. The SHPB rod only contacts the outer end face of the piston and does not bear static load. The SHPB rod only transmits dynamic impact force, and the axial static load is directly applied in a balanced manner through the first piston 8 and the second piston 9 (the cross-sectional areas and impedances of the first piston 8 and the second piston 9 are symmetrical, and the output force of the first loading cylinder 2 is assumed to be...). F L The output of the second loading cylinder 5 is F R Controlled by the same servo valve and the same controller, it meets the requirements. F L = F R = F static The static compressive stress acting on specimen 10 is The total stress borne by specimen 10 , The static axial stress on specimen 10, for The static axial stress on specimen 10 at time moment for The static load sensor only measures the dynamic impact force at any given moment. F static Unaffected by dynamic waves, dynamic and static loads do not interfere with each other, achieving strict physical path separation between static and dynamic loads. The static load sensor always measures only static force and is not affected by dynamic waves (the incident rod 1 and the transmission rod 6 are in contact with the outer end faces of the first piston 8 and the second piston 9 respectively but are not connected, which can eliminate the interference of secondary incident waves). After the impact is completed, the hydraulic cylinder servo system can continue to maintain pressure, and the static load will not be released, thus supporting creep and relaxation experiments for up to seven days to six months after the impact disturbance.

[0046] Furthermore, this application adds a high-frequency servo confining pressure stabilization module and a dual sampling rate data acquisition and fusion module, which can suppress confining pressure fluctuations caused by dynamic impacts and obtain complete dynamic and static combined stress-strain curves.

[0047] Traditional devices typically employ symmetrical synchronous control with two cylinders on the left and right sides. During impact, the pressure on one side decreases while the pressure on the other side increases, causing the servo systems on both sides to pull against each other, resulting in a large response delay. In this embodiment, preferably, as follows... Figure 3As shown, the dynamic-static separation loading structure employs asymmetric axial pressure compensation control: the first loading cylinder 2 uses a large buffer chamber with a fixed volume as the passive support end; the second loading cylinder 5 uses a high-frequency servo valve for active control as the dynamic compensation end. During dynamic impact, the first piston 8 moves backward under the impact force of the incident rod 1, increasing the volume of the large buffer chamber of the first loading cylinder 2 and causing a sudden drop in pressure. The high-frequency servo valve of the second loading cylinder 5 detects the pressure change and quickly releases pressure to compensate, keeping the total axial pressure fluctuation within five percent of the set value. The formula for calculating the pressure fluctuation of the large buffer chamber of the first loading cylinder 2 is provided. ,in This represents the pressure change in the first loading cylinder 2. The bulk elastic modulus of the medium in the large buffer chamber of the first loading cylinder 2, For the cross-sectional area of ​​the first piston 8, For the displacement of the first piston 8, The initial volume of the two large buffer chambers of the first loading cylinder ( >500cm³), due to The pressure fluctuation of the first loading cylinder 2 is significantly suppressed, and the second loading cylinder 5 controls the total fluctuation within a certain range through active compensation. ,in The total axial compression change The change in output force of the first loading cylinder 2, The change in output force of the second loading cylinder 5, The initial axial pressure value is set. This device adopts asymmetric axial pressure compensation control, which simplifies the traditional dual-control dual-compensation to single-end active compensation, reducing the number of servo control ports by half, reducing system complexity and cost, while improving response speed, ensuring axial pressure stability during impact, and providing accurate initial conditions for subsequent long-term tests.

[0048] To further reduce the axial pressure fluctuation of the first loading cylinder 2, the large buffer chamber of the first loading cylinder 2 is filled with hydraulic oil and compressible nitrogen, and the chamber of the second loading cylinder 5 is filled with hydraulic oil. The bulk elastic modulus of the gas (about 1~2 MPa) is much smaller than that of the hydraulic oil (about 1.5 GPa). When the first piston 8 is impacted and moves backward, the gas medium produces a large compressible deformation, absorbing the impact energy, which significantly reduces the pressure change rate of the first loading cylinder 2 (under the same volume deformation, the pressure fluctuation on the gas side is only one-thousandth of that on the oil side). The gas side acts as an elastic cushion, while the hydraulic side maintains high-precision servo control. The two work together to achieve a hybrid effect of "soft buffer + hard control".

[0049] The design of the confining pressure cavity volume traditionally relies on trial and error based on experience. In this embodiment, the volume of the confining pressure cavity is preferably determined by... ;in: The bulk elastic modulus of the hydraulic oil within the confining pressure cavity; For the volume change of sample 10, we have , The initial volume of sample 10, For the volumetric strain of sample 10, we have , This represents the axial strain increment of specimen 10. The radial strain increment of specimen 10, and , The Poisson's ratio of sample 10 (usually 0.2~0.35); The initial confining pressure value is set. During dynamic impact, specimen 10 is subjected to axial compression, resulting in radial expansion (Poisson effect). This volume change... This will compress the hydraulic oil in the confining pressure chamber, causing the confining pressure to rise and change. The change in volume satisfies: In the formula The volume of the oil in the confining pressure chamber is approximately equal to the volume of the confining pressure chamber itself. To ensure that the confining pressure fluctuation does not exceed 5% of the initial confining pressure, i.e. Then it is necessary By designing a sufficiently large , making The pressure is always kept within acceptable limits. Furthermore, the symmetrical oil circuit design of pressure chamber 4 allows oil pressure fluctuations to self-cancel within the chamber. This scheme achieves quantitative design of the confining pressure chamber volume, changing the traditional reliance on trial and error and ensuring that confining pressure fluctuations are always controlled within 5% of the set value.

[0050] In this embodiment, preferably, the high-frequency servo confining pressure stabilization module adopts a high-frequency servo pressure relief control strategy: when the pressure sensor detects an increase in confining pressure, the controller drives the servo valve to quickly open the oil drain channel and release the pressure. Oil, making Discharge speed satisfy: ,in for The discharge speed at all times, For flow coefficient, for The opening area of ​​the servo valve at any given time. for Constant pressure, For return oil pressure, The density of the hydraulic oil within the confining pressure chamber is defined as follows: Through active pressure relief compensation, excess oil caused by dynamic impact is rapidly released, further improving the dynamic stability of the confining pressure and ensuring the effective establishment of the dynamic stress balance criterion.

[0051] In this embodiment, preferably, as follows: Figure 3 As shown, the high-frequency servo confining pressure stabilization module adopts a shock wave synchronous trigger-prediction-compensation timing control strategy: the incident wave signal is monitored in real time by the strain gauge on the incident rod 1. When the strain gauge detects that the incident wave amplitude exceeds the set threshold, the signal is used as the trigger source to advance the response. Time sends feedforward compensation commands to the controller, where, The distance from the strain gauge to the first piston 8. The elastic wave velocity in incident rod 1 ( Approximately 5000 m / s , The controller pre-adjusts the servo valve opening area before the shock wave reaches the first piston 8, ensuring that the axial pressure is already in a pre-compensated state at the moment of impact. In traditional devices, servo compensation usually only starts after the pressure sensor detects the fluctuation, resulting in unavoidable detection delay and valve response delay (typically 2~5 ms). For dynamic shocks lasting only 100~200 μs, this passive compensation is often lagging. This device adopts a shock wave synchronous trigger-prediction-compensation timing control strategy. This "preemptive" control strategy shortens the compensation response time from the traditional "detection delay + valve delay" to only the valve mechanical delay, improving the real-time performance of axial pressure maintenance.

[0052] In this embodiment, preferably, the dual-sampling-rate data acquisition and fusion module includes a hardware synchronization triggering unit, a static acquisition channel operating at a first sampling rate, a dynamic acquisition channel operating at a second sampling rate, and a data fusion processor; the hardware synchronization triggering unit generates a synchronization trigger signal based on the same physical event, simultaneously activating the static acquisition channel and the dynamic acquisition channel to achieve microsecond-level time synchronization; the data fusion processor is used to perform time alignment, vibration decoupling, stress correction, and cross-channel splicing of the two sets of data to reconstruct a complete dynamic-static combined full stress-strain curve.

[0053] In this embodiment, preferably, as follows: Figure 3As shown, the hardware synchronization triggering unit includes a trigger strain gauge attached to the incident rod 1, a threshold discrimination circuit, and a TTL pulse generator. The trigger strain gauge is connected to the first channel of the ultra-dynamic strain gauge. When the bullet impacts the incident rod 1, the trigger strain gauge detects the incident wave signal. After passing through the threshold discrimination circuit, the TTL pulse generator generates a TTL rising edge pulse signal and simultaneously outputs it to the external trigger port of the ultra-dynamic strain gauge. This activates the dynamic acquisition channel for high-speed acquisition at a sampling rate of 10 MHz, and activates the static acquisition channel for data stream interruption marking at a sampling rate of 10 kHz. The static and dynamic acquisition channels are synchronously activated by the same TTL rising edge, achieving a time synchronization accuracy of ±1 μs. This hardware-level solution fundamentally solves the problem of different time references between the static and dynamic systems, laying the physical foundation for subsequent accurate data stitching and serving as the first step and key prerequisite for dynamic and static data fusion.

[0054] In dynamic and static combined loading tests, data fusion processing has long faced the following four levels of technical challenges: 1) Different time reference sources lead to data splicing incompatibility: The static triaxial loading system uses a fully digital servo controller with a sampling rate of 10 kHz, and the time reference is provided by the controller's internal clock. The dynamic SHPB system, on the other hand, uses an ultra-dynamic strain gauge with a sampling rate of 10 MHz, and the time reference is provided by the strain gauge's own clock. The two systems operate independently, and the physical moment of impact cannot be precisely aligned in the two sets of data, inevitably resulting in time misalignment or overlap when splicing dynamic and static data; 2) Signal aliasing and distortion of static sensors at the moment of impact: The impact duration is approximately 100~300 μs, which happens to cover the natural vibration frequency of the compression bar and frame (typically 500 Hz~5 Hz). 1) The signals collected by the static displacement sensor and pressure sensor at the moment of impact are not the actual deformation of the specimen 10, but a mixture of the inertial displacement of the compression bar, the resonance of the frame and the deformation of the specimen 10. Direct reading will lead to a serious overestimation of permanent deformation; 2) The dynamic strain gauge cannot give the residual state after impact: The SHPB strain gauge can only measure the dynamic stress wave and cannot reflect the residual strain of the specimen 10 after the impact. The static LVDT is still in the vibration decay period within a few milliseconds after the impact, and the reading is unreliable. Therefore, the true initial state after impact, that is, the starting point of creep or relaxation test, has long lacked an accurate means of measurement; 3) The difference between dynamic and static sampling rates creates a huge data gap: There is a 1000-fold difference in sampling rates between 10 kHz and 10 MHz. Direct interpolation will lead to the loss of dynamic details or distortion of static trends.

[0055] Therefore, this application features a specially designed data fusion processor: In this embodiment, preferably, the data fusion processor includes: Time alignment unit, used to align all data based on absolute time; An adaptive filtering unit is used to filter the measured signal from the static acquisition channel to separate the deformation and vibration noise of the real sample 10. The dynamic-static deformation decoupling unit is used to remove inertial displacement from the measured signal to obtain the actual dynamic deformation of the sample 10; The circumferential deformation indirect measurement unit is used to indirectly measure the circumferential deformation of the sample 10; The triaxial static load correction unit is used to correct dynamic stress so that the absolute reference of the dynamic stress curve is consistent with the static load system. The data stitching unit is used to stitch together the pre-impact static segment, the dynamic segment during impact, the transition fusion segment, and the post-impact static segment to form a complete stress-strain curve.

[0056] Hardware synchronization only solves the problem of simultaneous startup. Setting up a time alignment unit allows the zero-point time of dynamic and static data to be aligned based on the physical laws of stress wave propagation. During impact, the measured signal from the static acquisition channel is composed of the superposition of deformation and vibration noise from the actual sample 10. An adaptive filtering unit is set up to eliminate vibration noise. During dynamic impact, the superposition of deformation of the actual sample 10 and inertial displacement of the incident rod 1 caused by the shock wave makes it impossible to directly read the deformation of the sample 10. A dynamic-static deformation decoupling unit is set up to eliminate the inertial displacement of the incident rod 1, ensuring the accuracy of dynamic deformation data. Due to the limitations of chamber space and high-pressure sealing requirements, it is difficult to directly arrange circumferential strain gauges on the surface of the sample 10. An indirect circumferential deformation measurement unit is set up to indirectly measure the circumferential deformation of the sample 10. Traditional... The SHPB two-wave / three-wave method assumes that specimen 10 has no initial static load. However, in reality, specimen 10 is subjected to a triaxial static load. The stress wave generated by the dynamic impact is a transient increment superimposed on the static load. More importantly, the static load servo system is compensating at the moment of impact, and the static load itself has a slight fluctuation. This fluctuation is not negligible on the dynamic time scale (microsecond level) and must be accurately separated from the dynamic stress. Setting up a triaxial static load correction unit can ensure that the absolute reference of the dynamic stress curve is consistent with the static load system, avoiding the error of the traditional assumption that the dynamic stress starts from zero. The data stitching unit realizes seamless stitching of the static segment before impact, the dynamic segment during impact, the transition fusion segment, and the static segment after impact. For the first time, a complete stress-strain curve covering the entire evolution from microsecond-level dynamic response to day-month-level aging is obtained.

[0057] In this embodiment, preferably, the working principle of the time alignment unit is as follows: the physical time when the stress wave reaches the end face of the sample 10 is taken as the physical time zero point of the dynamic channel. , , This refers to the time when the TTL trigger pulse is emitted. Let be the propagation time of the stress wave from the trigger point to the end face of specimen 10. , The distance from the strain gauge on the incident rod 1 to the first piston 8 is [missing information]. The elastic wave velocity in incident rod 1; dynamic data is... As an absolute time reference, pre-calibration determines the relative time difference of the static channel. Static channel data overall translation Post-alignment. Because the sensors in the static channel are mounted on the frame of pressure chamber 4, their signal propagation path differs from that of the pressure rod, resulting in a fixed system delay. A pre-calibration experiment (such as gently tapping the incident rod 1 to generate a weak vibration at a known time, and comparing the responses of the two channels) determines the relative time difference of the static channel. The time alignment unit is based on the physical laws of stress wave propagation rather than simple interpolation alignment, ensuring precise synchronization of the two sets of data in a physical sense, fundamentally eliminating time misalignment.

[0058] In this embodiment, preferably, the adaptive filtering unit works by using a 4th-order Butterworth low-pass filter, whose frequency response function is: The filter order n=4, and the cutoff frequency is automatically adjusted based on the reflected wave energy (measured by the oscilloscope channel). ,in The initial cutoff frequency, The adjusted cutoff frequency. For adaptive coefficients, For the energy of the reflected wave, The maximum reflected wave energy is [value missing]. During the impact, the vibration noise mainly originates from the inertial vibration of the incident rod 1 and the frame. Its spectral characteristics are related to the impact intensity, and the stronger the impact, the richer the high-frequency components. Generally, the natural fundamental frequency of the frame-compression rod system is usually higher than 1.5 kHz, while the effective frequency components of the static deformation of the sample 10 are lower than 0.5 kHz, and the cutoff frequency [value missing]. f c A frequency of 1 kHz can effectively separate the two, but when the impact intensity is low, the frame vibration energy is weak, and the dominant vibration frequency may be lower than 1 kHz. Appropriately increasing the frequency is necessary. To retain more static details, the filter cutoff frequency is adaptively adjusted according to the impact intensity, which effectively eliminates high-frequency vibration noise of the frame and retains the true static deformation signal of sample 10 to the greatest extent, thus achieving a dynamic balance between noise suppression and signal fidelity.

[0059] In this embodiment, preferably, the working principle of the dynamic-static deformation decoupling unit is as follows: the strain gauge channel synchronously acquires reflected wave signals. Through reflected wave signals Estimate the inertial displacement of incident rod 1 ,in, The transfer coefficient between the frame and incident rod 1 was determined through calibration tests. The distance from the strain gauge to the first piston 8. The elastic wave velocity in incident rod 1; from the measured signal Remove the inertial displacement of incident rod 1 The dynamic deformation of real sample 10 was obtained: During dynamic impact, the measured signal from the axial displacement sensor... y ( t It consists of two parts: 10 real specimens with deformation. x ( t and the inertial displacement of the incident rod 1 caused by the shock wave. n ( t The overlap of the two factors makes it impossible to directly read the deformation of sample 10. The dynamic and static deformation decoupling unit effectively separates the interference of frame resonance and column inertial vibration on displacement measurement during the impact process, solves the problem of static sensor signal overlap and distortion in the prior art, and ensures the accuracy of dynamic deformation data.

[0060] In this embodiment, preferably, the working principle of the circumferential deformation indirect measurement unit is: based on the indirect measurement method of volume conservation, the axial deformation of the sample 10 is measured in real time. Changes in the volume of oil in the confining pressure chamber (Monitored by cylinder displacement or flow meter), based on the volume conservation equation Radial deformation of sample 10 was reversed. Thus, the circumferential strain is obtained. ,in, This represents the volume change of sample 10. The sample diameter is 10. The height of specimen 10 is shown. It eliminates the need to attach circumferential strain gauges to the surface of specimen 10, solving the technical challenge of directly measuring circumferential deformation under high-pressure triaxial conditions, while simultaneously improving measurement reliability and testing efficiency.

[0061] In this embodiment, preferably, the working principle of the triaxial static load correction unit is: using the triaxial corrected dynamic stress formula. ,in The steady-state static load before impact is determined by the average value of the pre-impact in the static channel. For the dynamic stress calculated by the SHPB three-wave method, To compensate for static load servo fluctuations, data is recorded from the static channel at a sampling rate of 10 kHz, upsampled to a 10 MHz time axis using cubic spline interpolation, and then superimposed point-to-point with the dynamic data. This precisely isolates and corrects the minute fluctuations of static load servo compensation at the moment of impact from the dynamic stress, avoiding the error of the traditional assumption that dynamic stress starts from zero, and ensuring that the absolute benchmark of the dynamic stress curve is consistent with that of the static load system.

[0062] In this embodiment, preferably, as follows: Figure 3 As shown, the working principle of the data splicing unit is as follows: Define transition time window ,in The end time of the dynamic process. This is the moment when the static vibration has completely decayed. Transitional fusion stress for: , in, The weighting coefficients for dynamic data (ensuring a smooth transition from dynamic to static data without abrupt changes) adopt an exponential decay form. , The transition time constant; The dynamic stress calculated using the SHPB three-wave method; The filtered static stress; Permanent deformation caused by impact for:

[0063] in, This represents the average strain during the statically stable phase after the impact. The static stabilization period after the impact (the time interval corresponding to the average value within 100 ms after the vibration decay is complete). This represents the average strain during the statically stable phase before impact. The static stable period before the trigger (the time interval corresponding to the average value within 100 ms before triggering); The complete strain data after the impact is stitched together as follows:

[0064] in, For the complete strain sequence of sample 10, Strain measured in a static channel. This represents the static stability strain value before impact. For dynamic strain increments, To facilitate integration and adaptation during the transition period; The complete stress splicing is as follows:

[0065] in, For the complete stress sequence of sample 10, Stress measured in the static channel. This represents the filtered static stress.

[0066] A dual-channel weighted fusion algorithm was used to process the transition period data after the impact. After the impact, the specimen 10 underwent permanent deformation (plastic deformation). This value is the initial condition for subsequent creep / relaxation tests. It is essential to accurately extract the key initial condition of permanent deformation. Since the static channel is still in the vibration decay period after the impact, direct reading will produce errors. Therefore, the method of subtracting permanent deformation from the average strain is adopted.

[0067] Furthermore, in this embodiment, preferably, the data fusion processor further includes a consistency verification unit, which employs a multi-channel cross-validation mechanism to verify the reliability of the data fusion. Under static steady state, axial compression Confining pressure Axial deformation of sample 10 and radial deformation The consistency constraints of the rock mechanics constitutive relation should be satisfied: , , ,

[0068] in, For axial stress, The cross-sectional area of ​​sample 10 is... For confining pressure stress, For axial strain, The initial height of sample 10 For radial strain, The initial diameter of sample 10; For the linear elastic stage, the generalized Hooke's law should be satisfied: ,

[0069] in, The elastic modulus of the rock. The Poisson's ratio of the rock; The system calculates the residuals in real time: ,

[0070] in, For axial strain consistency residuals, For radial strain consistency residuals; If the residual exceeds the set threshold, it is determined that there is drift or poor contact in a certain channel. The system will automatically mark the data for that period and prompt for recalibration.

[0071] The consistency verification unit ensures the physical consistency between the 10 kHz and 10 MHz data sets, ensuring that the fused data conforms to the consistency constraints of rock mechanics constitutive relations, effectively preventing fusion errors caused by sensor failures, and greatly improving the reliability of experimental data.

[0072] In this embodiment, the long-term pressure holding and aging test module includes: The pressure holding control unit is used to close the oil drain valve of the confining pressure chamber after the impact is completed, so that the servo system enters the pressure holding mode. The first loading cylinder 2 provides flexible support, and the servo valve of the second loading cylinder 5 performs zero-point drift compensation. It can operate continuously under the conditions of confining pressure fluctuation ≤3% and axial pressure fluctuation ≤2%. The aging data recording unit is used to continuously record the deformation data of the sample 10 at a third sampling rate lower than the first sampling rate during the pressure holding period, so as to draw creep curves or relaxation curves and realize the study of the long-term aging evolution law after impact disturbance.

[0073] The embodiments described above are some, but not all, of the embodiments of this application. The detailed description of the embodiments of this application is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

Claims

1. A dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks, comprising: Dynamic Hopkinson bar module for generating and measuring dynamic shock waves, including incident and transmission bars and strain gauges on the bars; A static triaxial loading module for applying static axial pressure includes a first loading cylinder and its first piston, a second loading cylinder and its second piston, a pressure chamber, and a load-bearing frame. The device is characterized in that: The dynamic Hopkinson pressure bar module and the static triaxial loading module form a dynamic-static separation loading structure: the first piston and the second piston are separately set from the first loading cylinder and the second loading cylinder, respectively, and are in direct contact with both ends of the sample but not in direct contact with the pressure chamber; the incident rod and the transmission rod are in contact with the outer end faces of the first piston and the second piston, respectively, but are not connected; the static axial pressure is provided by the first loading cylinder and the second loading cylinder, and the dynamic balance of the first piston and the second piston is achieved through the parallel pipeline of the first loading cylinder and the second loading cylinder, without being transmitted through the incident rod or the transmission rod; the dynamic shock wave is transmitted from the incident rod through the first piston, the sample, and the second piston to the transmission rod, without being transmitted through the cylinder structure; The device further includes: A high-frequency servo confining pressure stabilization module is used to suppress confining pressure fluctuations caused by dynamic impacts, including the confining pressure chamber and its servo valve and controller; The dual sampling rate data acquisition and fusion module is used to simultaneously acquire static and dynamic data and fuse the two sets of data to obtain a complete dynamic-static combined full stress-strain curve; The dynamic-static separation loading structure adopts asymmetric axial pressure compensation control: the first loading cylinder uses a large buffer chamber with a fixed volume as a passive support end; the second loading cylinder uses a high-frequency servo valve for active control as a dynamic compensation end; during dynamic impact, the first piston moves backward under the impact force of the incident rod, the volume of the large buffer chamber of the first loading cylinder increases and the pressure drops instantaneously, and the high-frequency servo valve of the second loading cylinder detects the pressure change and quickly releases pressure to compensate, so that the total axial pressure fluctuation is controlled within five percent of the set value; The dual-sampling-rate data acquisition and fusion module includes a hardware synchronization triggering unit, a static acquisition channel operating at the first sampling rate, a dynamic acquisition channel operating at the second sampling rate, and a data fusion processor. The hardware synchronization triggering unit generates a synchronization trigger signal based on the same physical event, simultaneously activating the static and dynamic acquisition channels to achieve microsecond-level time synchronization. The data fusion processor is used to perform time alignment, vibration decoupling, stress correction, and cross-channel splicing of the two sets of data to reconstruct a complete dynamic-static combined full stress-strain curve.

2. The dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks as described in claim 1, characterized in that, The large buffer chamber of the first loading cylinder is filled with hydraulic oil and compressible nitrogen, while the chamber of the second loading cylinder is filled with hydraulic oil.

3. The dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks as described in claim 1, characterized in that, Volume of confining pressure cavity ;in: The bulk elastic modulus of the hydraulic oil within the confining pressure cavity; Let be the volume change of the sample, where , The initial volume of the sample. Let be the volumetric strain of the specimen, where , This represents the axial strain increment of the specimen. Let be the radial strain increment of the specimen, and , The Poisson's ratio of the sample; Set the initial confining pressure value.

4. The dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks as described in claim 3, characterized in that, The high-frequency servo confining pressure stabilization module employs a high-frequency servo pressure relief control strategy: when an increase in confining pressure is detected, the controller drives the servo valve to quickly open the oil relief channel, releasing the pressure. Oil, making Discharge speed satisfy: ,in for The discharge speed at all times, For flow coefficient, for The opening area of ​​the servo valve at any given time. for Constant pressure, For return oil pressure, The density of the hydraulic oil in the confining pressure chamber.

5. The dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks as described in claim 1, characterized in that, The high-frequency servo confining pressure stabilization module employs a shock wave synchronous trigger-prediction-compensation timing control strategy: the incident wave signal is monitored in real time by strain gauges on the incident rod; when the strain gauges detect that the incident wave amplitude exceeds a set threshold, the signal is used as the trigger source to advance the response. Time sends feedforward compensation commands to the controller, where, The distance from the strain gauge to the first piston. To determine the elastic wave velocity in the incident rod, the controller pre-adjusts the opening area of ​​the servo valve before the shock wave reaches the first piston, so that the axial pressure is already in a pre-compensated state at the moment of impact.

6. The dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks as described in claim 5, characterized in that, The hardware synchronization triggering unit includes a trigger strain gauge attached to the incident rod, a threshold discrimination circuit, and a TTL pulse generator. The trigger strain gauge is connected to the first channel of the ultra-dynamic strain gauge. When the bullet hits the incident rod, the trigger strain gauge detects the incident wave signal. After passing through the threshold discrimination circuit, the TTL pulse generator generates a TTL rising edge pulse signal and simultaneously outputs it to the external trigger port of the ultra-dynamic strain gauge. This activates the dynamic acquisition channel for high-speed acquisition at a sampling rate of 10 MHz and activates the static acquisition channel for data stream interruption marking at a sampling rate of 10 kHz. The static acquisition channel and the dynamic acquisition channel are synchronously activated by the same TTL rising edge, achieving a time synchronization accuracy of ±1 μs.

7. The dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks as described in claim 1 or 6, characterized in that, The data fusion processor includes: Time alignment unit, used to align all data based on absolute time; An adaptive filtering unit is used to filter the measured signal from the static acquisition channel to separate the actual sample deformation and vibration noise. The dynamic-static deformation decoupling unit is used to remove inertial displacement from the measured signal to obtain the true dynamic deformation of the sample; Circumferential deformation indirect measurement unit, used to indirectly measure the circumferential deformation of the specimen; The triaxial static load correction unit is used to correct dynamic stress so that the absolute reference of the dynamic stress curve is consistent with the static load system. The data stitching unit is used to stitch together the pre-impact static segment, the dynamic segment during impact, the transition fusion segment, and the post-impact static segment to form a complete stress-strain curve.

8. The dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks as described in claim 7, characterized in that, The working principle of the time alignment unit is as follows: the physical time when the stress wave arrives at the end face of the sample is taken as the physical time zero point of the dynamic channel. , , This refers to the time when the TTL trigger pulse is emitted. Let be the propagation time of the stress wave from the trigger point to the end face of the specimen. , The distance from the strain gauge on the incident rod to the first piston is denoted as . The elastic wave velocity in the incident rod; dynamic data is... As an absolute time reference, pre-calibration determines the relative time difference of the static channel. Static channel data overall translation Back alignment.

9. The dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks as described in claim 7, characterized in that, The adaptive filtering unit works by using a 4th-order Butterworth low-pass filter, whose frequency response function is: The filter order n=4, and the cutoff frequency is automatically adjusted according to the reflected wave energy. ,in The initial cutoff frequency, The adjusted cutoff frequency. For adaptive coefficients, For the energy of the reflected wave, This represents the maximum reflected wave energy.

10. The dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks as described in claim 7, characterized in that, The working principle of the dynamic-static deformation decoupling unit is: the strain gauge channel synchronously acquires reflected wave signals. Through reflected wave signals Estimate the inertial displacement of the incident rod ,in For the inertial displacement of the incident rod, The transfer coefficient between the frame and the incident rod was determined through calibration tests. The distance from the strain gauge to the first piston. The elastic wave velocity in the incident rod; from the measured signal Remove the inertial displacement of the incident rod The dynamic deformation of the actual sample was obtained: , This represents the dynamic deformation of a real sample.

11. The dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks as described in claim 7, characterized in that, The working principle of the circumferential deformation indirect measurement unit is: based on the indirect measurement method of volume conservation, it measures the axial deformation of the sample in real time. Changes in the volume of oil in the confining pressure chamber According to the volume conservation equation Reverse calculation of radial deformation of the specimen Thus, the circumferential strain is obtained. ,in, This represents the volume change of the sample. The diameter of the sample is 1. This represents the height of the sample.

12. The dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks as described in claim 7, characterized in that, The working principle of the triaxial static load correction element is: it uses the triaxial corrected dynamic stress formula. ,in For triaxial correction of dynamic stress, The steady-state static load before impact is determined by the average value of the pre-impact in the static channel. For the dynamic stress calculated by the SHPB three-wave method, To compensate for fluctuations under static load servo conditions, data is recorded from a static channel at a sampling rate of 10 kHz, upsampled to a 10 MHz time axis through cubic spline interpolation, and then superimposed point-to-point with the dynamic data.

13. The dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks as described in claim 7, characterized in that, The working principle of the data splicing unit is as follows: Define transition time window ,in The end time of the dynamic process. This is the moment when the static vibration has completely decayed. Transitional fusion stress for: ， in, The weighting coefficients for dynamic data adopt an exponential decay form. , The transition time constant; The dynamic stress calculated using the SHPB three-wave method; The filtered static stress; Permanent deformation caused by impact for: in, This represents the average strain during the statically stable phase after the impact. This is the static stability period following the impact; This represents the average strain during the statically stable phase before impact. This is the static and stable period before the impact; The complete strain data after the impact is stitched together as follows: in, This is the complete strain sequence of the specimen. Strain measured in a static channel. This represents the static stability strain value before impact. For dynamic strain increments, To facilitate integration and adaptation during the transition period; The complete stress splicing is as follows: in, For a complete stress sequence of the specimen, Stress measured in the static channel. The filtered static stress, This refers to the physical moment when the stress wave reaches the end face of the sample, i.e., the physical time zero point of the dynamic channel. For triaxial correction of dynamic stress, For steady-state static load before impact, This is for static load servo compensation fluctuations.

14. The dynamic-static separation experimental apparatus for measuring the triaxial dynamic mechanical properties of rocks as described in claim 7, characterized in that, The data fusion processor also includes a consistency verification unit, which uses a multi-channel cross-validation mechanism to verify the reliability of the data fusion. Under static steady state, axial compression Confining pressure Axial deformation of the specimen and radial deformation The consistency constraints of the rock mechanics constitutive relation should be satisfied: , ， ， in, For axial stress, The cross-sectional area of ​​the sample. For confining pressure stress, For axial strain, The initial height of the sample. For radial strain, The initial diameter of the sample; For the linear elastic stage, the generalized Hooke's law should be satisfied: , in, The elastic modulus of the rock. The Poisson's ratio of the rock; The system calculates the residuals in real time: , in, For axial strain consistency residuals, For radial strain consistency residuals; If the residual exceeds the set threshold, it is determined that a certain channel has drift or poor contact. The system will automatically mark the data for that period and prompt for recalibration.

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