Fault stress disturbance physical simulation system and method

Abstract

The invention discloses a fault stress disturbance physical simulation system and method, and relates to the technical field of oil and gas field development. A physical simulation system for disturbance of a fault stress field comprises a strain calculation module which is used for calculating data of a 3D displacement field, a 3D strain field and a 3D deformation field of an object to be measured in the loading process through three-dimensional reconstruction and a digital image correlation algorithm according to surface feature changes of an image of the object to be measured; and the model optimization module is used for adjusting a digital modeling design method according to the data of the 3D displacement field, the 3D strain field and the 3D deformation field to obtain an optimal modeling method. In addition, the invention further discloses a fault stress field disturbance physical simulation system based on the system. According to the method, the problem of verifying the accuracy of a finite element solution result is solved, the modeling technology is optimized and adjusted, the optimal modeling method is conveniently obtained and popularized and applied to three-dimensional modeling, and therefore the disturbance rule of a fault on ground stress is found out.

Description

Technical Field

[0001] The invention relates to the technical field of oil and gas field development, and in particular to a fault stress disturbance physical simulation system and method. Background Art

[0002] Geostress plays an important role in the integrated development of tight gas geological engineering. Accurate identification of the direction of geostress helps to more accurately design the best combination of the orientation of natural fractures, artificial fractures and wellbore trajectories; through the detailed interpretation of geostress around the well, it helps to optimize drilling parameters, reduce various complexities such as wellbore collapse and leakage, and shorten the drilling cycle; the magnitude of geostress determines whether the formation can be compressed, the geostress difference is the main controlling factor of the complexity of the fracture, and the geostress direction controls the extension direction of the fracture. The application of geostress runs through the entire process of tight gas development. Former researchers have made rapid progress in several aspects of technology, including geostress testing based on cores and hydraulic fracturing, geostress prediction based on acoustic logging and seismic inversion, and numerical simulation based on finite elements. In actual engineering, engineers have realized that geostress has obvious heterogeneity in both the vertical and horizontal directions. The main controlling factors and their influencing mechanisms that cause these irregular changes in stress fields are not fully studied at present, but it is a general consensus that faults have a strong disturbance to the stress field. Understanding the disturbance law of faults on ground stress is of great significance to regional stress research.

[0003] Theoretical research on the stress field distribution at the tip of a single crack in a homogeneous plane still requires the establishment of partial differential equations through complex functions, and the solution process is often extremely complicated. Therefore, numerical solution has become the most commonly used method for fault stress disturbance. However, the unit division, shape function selection, iteration parameter selection, correct initial values ​​and boundary conditions, and appropriate criterion selection will have a significant impact on the accuracy and results of the simulation. Therefore, it is necessary to establish an experimental method for verifying the accuracy of finite element solution results in order to optimize and adjust the modeling technology.

[0004] The physical simulation of fault stress field disturbance is invisible and intangible. Some scholars have also tried to explore this direction in the research literature and proposed to use photoelastic experiments to visualize stress fields. The experiment needs to be based on transparent plastic materials such as acrylic as experimental samples, relying on strict optical design to present stress difference patterns under stress. This experiment has an inherent defect, that is, the sample material cannot reflect the true situation of the formation, and the experimental results are difficult to quantify, and the subsequent support research capabilities are insufficient. Therefore, there is a need for a physical simulation system for fault stress field disturbance to solve the problem that the accuracy of finite element solution results cannot be verified. Summary of the invention

[0005] The technical problem to be solved by the present invention is how to verify the accuracy of the finite element solution results and optimize and adjust the modeling technology. The purpose is to provide a fault stress field disturbance physical simulation system to solve the above problems.

[0006] The technical problem to be solved by the present invention is how to verify the accuracy of the finite element solution results and optimize and adjust the modeling technology. The purpose is to provide a fault stress field disturbance physical simulation method to solve the above problems.

[0007] The present invention is achieved through the following technical solutions:

[0008] A fault stress field disturbance physical simulation system comprises a strain calculation module: used for calculating the surface feature changes of the image of the object to be tested through three-dimensional reconstruction and digital image correlation algorithm, and obtaining the 3D displacement field, 3D strain field and 3D deformation field data of the object to be tested during the loading process; and a model optimization module: used for adjusting the digital modeling design method according to the above 3D displacement field, the above 3D strain field and the above 3D deformation field data to obtain the optimal modeling method.

[0009] The above-mentioned fault stress disturbance physical simulation system includes a model application module; the above-mentioned model application module is used to apply the above-mentioned optimal modeling method to three-dimensional modeling to obtain the disturbance law of the fault on the ground stress.

[0010] The above-mentioned fault stress disturbance physical simulation system includes a stress implementation system and a deformation digitization monitoring system; the above-mentioned stress implementation system is used to simulate the in-situ ground stress of the above-mentioned object to be tested during the loading process; the above-mentioned deformation digitization monitoring system is used to collect digital speckle images of the above-mentioned object to be tested before and after loading and deformation through the above-mentioned stress implementation system, and identify surface feature changes through the digital speckle images for calculation by the above-mentioned strain calculation module.

[0011] The stress implementation system comprises a stress controller, a hydraulic station and a hydraulic loading system. The stress controller is used to control the hydraulic loading system through the hydraulic station to generate in-situ stress on the object to be tested.

[0012] The above-mentioned deformation digitization monitoring system includes a light source, at least one industrial camera, a deformation analysis processing station and a monitoring controller; the above-mentioned light source is used as the digital speckle of the above-mentioned object to be measured; the at least one industrial camera is used to obtain the digital speckle image of the surface of the above-mentioned object to be measured before and after deformation; the above-mentioned deformation analysis processing station is used to identify the surface feature changes of the above-mentioned object to be measured according to the digital speckle image; the above-mentioned monitoring controller is used to control the above-mentioned light source, at least one industrial camera and the above-mentioned deformation analysis processing station respectively.

[0013] The resolution of at least one of the above industrial cameras is 12 million at 30fps, the strain measurement accuracy of the above deformation analysis and processing station is 0.002%, and the maximum strain range of the above deformation analysis and processing station is 2000%.

[0014] The above deformation numerical monitoring system uses digital image correlation method to quantitatively analyze the full-field displacement and strain.

[0015] The digital image correlation method includes continuously dividing the speckle image of the object surface before deformation into a plurality of sub-areas of the same size as correlation areas, using the center point of the correlation area as the point to be measured, matching the divided correlation area with the speckle image of the object surface after deformation to obtain the image coordinates of the corresponding image sub-area and the center point of the sub-area, calculating the displacement of the point to be measured, and obtaining the strain information through numerical difference calculation.

[0016] The equipment parameter configuration of the above hydraulic station includes a test space net width ≥ 500, a test force of 0 to 1000 kN, a piston displacement of 100 mm, and control parameters including force and displacement.

[0017] The object to be tested is a core or a core simulation sample corresponding to the formation rock mass.

[0018] The object to be measured is a cube with a size of 50 mm to 150 mm.

[0019] A fault stress disturbance physical simulation method comprises the following steps: S1: using three-dimensional reconstruction and digital image correlation algorithm to calculate the surface feature changes of the image of the object to be tested during the loading process, 3D displacement field, 3D strain field and 3D deformation field data; S2: adjusting the digital modeling design method according to the above 3D displacement field, the above 3D strain field and the above 3D deformation field data to obtain the optimal modeling method.

[0020] The above-mentioned method for simulating the physical disturbance of fault stress comprises the following steps: S3: applying the above-mentioned optimal modeling method to three-dimensional modeling to obtain the disturbance law of the fault on the ground stress.

[0021] Before implementing step S1, the in-situ stress of the object to be tested during loading is simulated; the surface features of the object to be tested before and after loading and deformation are collected, and the changes in the surface features of the object to be tested are identified.

[0022] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0023] This application uses three-dimensional reconstruction and digital image correlation algorithms to obtain the corresponding coordinate changes of each pixel in the image, thereby calculating the 3D displacement field, 3D strain field and 3D deformation field data in the process, and then adjusting and optimizing the digital modeling design method, facilitating the promotion and application of three-dimensional modeling, and finding out the disturbance law of faults on ground stress. The present invention solves the verification of the accuracy of finite element solution results and realizes the optimization and adjustment of modeling technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope. For those of ordinary skill in the art, other relevant drawings can be obtained based on these drawings without creative work. In the drawings:

[0025] Figure 1 This is an example diagram of the method of the fault stress disturbance physical simulation experimental analysis system of Example 1 of the present application.

[0026] Figure 2 is a schematic diagram of a fault stress disturbance physical simulation experimental analysis system according to Example 1 of the present application;

[0027] Figure 3 is a schematic diagram of sample loading in Example 1 of the present application;

[0028] Figure 4 is a schematic diagram of the initial state of the sample of Example 1 of the present application;

[0029] Figure 5 is a schematic diagram of the loading completion state of Example 1 of the present application;

[0030] Figure 6 It is a flow chart of the digital image correlation method of Example 2 of the present application.

[0031] Marks and corresponding parts names in the attached drawings:

[0032] 1-control cabinet, 2-hydraulic station, 3-loading frame, 4-deformation numerical monitoring system. DETAILED DESCRIPTION

[0033] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with embodiments and drawings. The exemplary embodiments of the present invention and their description are only used to explain the present invention and are not intended to limit the present invention.

[0034] Example 1

[0035] like Figure 1 to Figure 5As shown, an embodiment of the present application provides a physical simulation system for fault stress field disturbance, including a strain calculation module: used to calculate the 3D displacement field, 3D strain field and 3D deformation field data of the object to be tested during the loading process through three-dimensional reconstruction and digital image correlation algorithm of the surface feature changes of the image of the object to be tested; a model optimization module: used to adjust the digital modeling design method according to the above-mentioned 3D displacement field, the above-mentioned 3D strain field and the above-mentioned 3D deformation field data to obtain the optimal modeling method.

[0036] (1) The embodiment of the present application obtains the corresponding coordinate changes of each pixel of the image through three-dimensional reconstruction and digital image correlation algorithm, thereby calculating the 3D displacement field, 3D strain field and 3D deformation field data in the process, and then inputs the above 3D displacement field, 3D strain field and 3D deformation field data into the model, adjusts and optimizes the digital modeling design method, facilitates the promotion and application of three-dimensional modeling, and finds out the disturbance law of fault on ground stress. The present invention solves the verification of the accuracy of the finite element solution results and realizes the optimization and adjustment of the modeling technology.

[0037] The above-mentioned fault stress disturbance physical simulation system includes a model application module; the above-mentioned model application module is used to apply the above-mentioned optimal modeling method to three-dimensional modeling to obtain the disturbance law of the fault on the ground stress.

[0038] The above-mentioned fault stress disturbance physical simulation system includes a stress implementation system and a deformation digitization monitoring system 4; the above-mentioned stress implementation system is used to simulate the in-situ ground stress of the above-mentioned object to be tested during the loading process; the above-mentioned deformation digitization monitoring system 4 is used to collect digital speckle images of the above-mentioned object to be tested before and after loading and deformation through the above-mentioned stress implementation system, and identify surface feature changes through the digital speckle images for calculation by the above-mentioned strain calculation module.

[0039] The stress implementation system comprises a stress controller, a hydraulic station 2 and a hydraulic loading system. The stress controller is used to control the hydraulic loading system through the hydraulic station 2 to generate in-situ stress on the object to be tested.

[0040] Specifically, the stress implementation system consists of a controller, a hydraulic station 2, and a hydraulic loading system, which can be used to simulate in-situ ground stress. Optionally, the hydraulic loading system uses a rigid loading device to apply an axial load, and the axial loading force that the device can apply should be greater than the force corresponding to the estimated maximum strength of the test specimen. The stress controller uses hydraulic servo control loading, and has two loading modes: load control and displacement control.

[0041] The above-mentioned deformation digitization monitoring system 4 includes a light source, at least one industrial camera, a deformation analysis processing station and a monitoring controller; the above-mentioned light source is used as the digital speckle of the above-mentioned object to be measured; the at least one industrial camera is used to obtain the digital speckle image of the surface of the above-mentioned object to be measured before and after deformation; the above-mentioned deformation analysis processing station is used to identify the surface feature changes of the above-mentioned object to be measured according to the digital speckle image; the above-mentioned monitoring controller is used to control the above-mentioned light source, at least one industrial camera and the above-mentioned deformation analysis processing station respectively.

[0042] The cameras can be two high-speed industrial cameras, which are used to obtain the digital speckle images before and after the deformation of the surface of the object to be measured. The main design of the deformation digitization monitoring system 4 adopts the principle of digital speckle three-dimensional full-field strain, including light source, high-speed industrial camera, controller and deformation analysis processing station, which can realize the real-time acquisition and analysis of sample plane and three-dimensional deformation.

[0043] The resolution of at least one of the above industrial cameras is 12 million at 30fps, the strain measurement accuracy of the above deformation analysis and processing station is 0.002%, and the maximum strain range of the above deformation analysis and processing station is 2000%.

[0044] The above-mentioned deformation numerical monitoring system 4 uses a digital image correlation method to perform quantitative analysis on the full-field displacement and strain.

[0045] The digital image correlation method includes continuously dividing the speckle image of the object surface before deformation into a plurality of sub-areas of the same size as correlation areas, using the center point of the correlation area as the point to be measured, matching the divided correlation area with the speckle image of the object surface after deformation to obtain the image coordinates of the corresponding image sub-area and the center point of the sub-area, calculating the displacement of the point to be measured, and obtaining the strain information through numerical difference calculation.

[0046] The digital image correlation method (DIC) is an optical experimental mechanics method for quantitative analysis of full-field displacement and strain. The basic idea of ​​this method is to select a sub-area (usually a rectangle) in the image before deformation, use the speckle grayscale information in the sub-area, find its corresponding position in the deformed image, and obtain the change of the sub-area position and shape. From this information, we can get the displacement and strain values ​​of the object at this point.

[0047] First, the digital speckle images of the object surface before and after deformation are obtained by using a camera. Secondly, the speckle images of the object surface before deformation are continuously divided into many small sub-areas of the same size (such as A and B areas) as relevant areas. The size of the relevant area is generally from 15×15 pixels to 30×30 pixels. The center point of the relevant area is used as the point to be measured, recorded as P, and then the segmented analysis area is matched with the speckle image of the object surface after deformation to obtain the image coordinates of the corresponding image sub-area and the center point of the sub-area (that is, the image coordinates of the point to be measured on the speckle image of the object surface after deformation). In this way, the displacement of the measured point P can be calculated, and the strain information can be obtained through further numerical difference calculation.

[0048] Compared with other optical mechanics methods, the advantages of digital image correlation method are: 1) The experiment is non-contact and non-destructive; 2) Its optical path is simple, and white light can be used as the light source; 3) The surface treatment technology is simple, and the required deformation information can be directly extracted from the random spots formed naturally or artificially on the surface of the object to be tested; 4) The measurement environment is not demanding, which is convenient for on-site engineering applications. For example, this method can realize micro-mechanics measurement in micro areas, and can be used for the measurement of mechanical quantities in harsh environments such as high temperature and high pressure, and in dynamic processes such as high-speed impact and vibration. Using microscopes and other auxiliary equipment, it can be applied to measurements of various situations from micro to macro.

[0049] The equipment parameter configuration of the hydraulic station 2 includes a test space net width ≥ 500, a test force of 0 to 1000 kN, a piston displacement of 100 mm, and control parameters including force and displacement.

[0050] Based on the principle of the above digital image correlation method, the following Figure 2 The key feature of the experimental fault stress disturbance experimental analysis system shown is that it can use the core or core simulation samples corresponding to the real formation rock mass to carry out simulated ground stress testing. Among them, the equipment function parameter design, the stress loading system should be able to meet the stable implementation of stress, and the loading capacity should be able to meet the maximum ground stress simulation requirements. The performance parameters of the stress implementation system are shown in Table 1 below.

[0051]

[0052]

[0053] Table 1

[0054] The deformation numerical monitoring system 4 should meet the following parameter requirements, as shown in Table 2 below:

[0055] Serial number Parameter name Parameter requirements 1 Camera resolution 12 million 2 Camera resolution 30fps 3 Strain measurement accuracy 0.002％ 4 Maximum strain range 2000％

[0056] Table 2

[0057] The object to be tested is a core or a core simulation sample corresponding to the formation rock mass.

[0058] The object to be measured is a cube with a size of 50 mm to 150 mm.

[0059] According to the principle of similarity, experimental samples are used to simulate the interaction between underground rock mass and faults. In order to be closer to the actual situation of the stratum, the core of the target layer is directly used as the sample.

[0060] Since the full-field test requires continuous photography of the sample surface, the core shape must first have a smooth plane, and in order to meet the loading requirements, 1 to 2 pairs of parallel loading surfaces are required, so the main shape of the sample is determined to be a cube. The maximum size of the sample is mainly limited by the preparation tools and the loading surface area, and the minimum size should avoid interference with the influence law caused by stress concentration at the loading boundary as much as possible. The main size is designed to be between 50mm and 150mm.

[0061] In order to meet the requirements of loading and imaging, the quality of sample preparation should be strictly controlled, and specifically the following requirements should be met: the loading surface should be flat, the parallelism of the opposite surfaces should be good, and the size difference measured by the caliper should not be greater than 0.05mm; the imaging surface should be clean and flat; the size cannot be lower than the minimum size requirement, and large-sized samples should be processed as much as possible.

[0062] The fault preparation method specifically includes making a crack on the side of the sample to simulate the local fault, using a mixture of curing agent + silicone to fully fill the crack gap, and then polishing the surface to make it smooth.

[0063] In order to enhance pixel recognition and tracking capabilities, white primer is sprayed on the surface of the fault sample to be tested, and then an appropriate amount of black topcoat is sprayed to increase the color difference, so that the stress and strain distribution characteristics around the fault can be better measured.

[0064] The sample loading method of the hydraulic loading system specifically includes: first, a single group stress loading method is used in the stress loading direction, and the blank direction is regarded as the reference and the loading direction is regarded as the stress difference by using the stress difference simulation method. Secondly, the stress loading method includes that a certain initial stress should be loaded on the sample first to ensure that the sample is compacted first, and cyclic loading can be performed first if necessary; the stress loading size should match the measured stress size of the research formation to simulate the stress difference; in order to ensure that the sample maintains a quasi-static state during the loading process, the stress loading rate should be stable to ensure deformation stability, and displacement-controlled stress loading is used, with a loading speed of 0.1mm / min.

[0065] During the experiment, the loading frame 3 used by the hydraulic loading system is connected to the main machine by selecting the loading pressure head corresponding to the sample size. The required controllers are integrated into the control cabinet 1 and connected to the imaging process to complete the preheating of each controller. According to the formation condition simulation, the target value of stress loading is designed according to the effective stress principle. According to the preset stress loading conditions and procedures, simulated ground stress loading is applied to the sample, and the digital speckle image acquisition is started simultaneously. The image analysis program is started to automatically calculate the three-dimensional deformation parameters of the sample surface, that is, the corresponding coordinate changes of each pixel of the image of the object to be measured are obtained through three-dimensional reconstruction and digital image correlation algorithms, so as to calculate the 3D displacement field, 3D strain field and 3D deformation field data in the process. The principal stress vector is calculated based on the above deformation parameters. The calculation method is the prior art and is not given as an example here. That is, the magnitude and direction of the principal stress are obtained by performing eigenvalue decomposition on the stress matrix. As Figure 4 Shown is the initial state of the digital speckle image before deformation, where the left image is the analysis area indicator and the right image is the maximum principal strain cloud map. Figure 5 The figure shows the loading completion state of the digital speckle image after deformation, where the left figure is the analysis area indication and the right figure is the maximum principal strain cloud map. The principal strain vector distribution curve is made based on the principal stress vector, and a three-dimensional model is established in combination with the preset fault geometry information conditions, such as fault plane, fault line, fault disk and displacement information, to summarize and analyze the disturbance relationship between the fault and the stress field.

[0066] Optionally, the familiarity criterion is used to present the relationship between the rock mass and the fault. Through basic research on fault simulation, the target layer underground or outcrop core is selected to simulate the rock mass around the fault. The sample fracture geometry is designed according to the fault geometric parameters. The fracture should be filled with fault fracture zone simulation objects, and the fault surface and the rock mass should be treated indistinguishably.

[0067] Optionally, to ensure correct image recognition, the imaging system is calibrated according to the standard process before the experiment and after the sample installation. The specific steps include: light adjustment → focal length adjustment → calibration plate identification (positive left) → calibration plate identification (positive oblique) → calibration plate identification (positive right) → calibration plate identification (reverse left) → calibration plate identification (reverse oblique) → calibration plate identification (reverse right) → calibration parameter calculation.

[0068] Optionally, similar to the preloading of the triaxial test, the specific method is to apply an initial stress of 5MPa to the sample to ensure that the internal defects of the sample are fully compacted and the contact surface is fully fitted. This process can be carried out through 2 to 3 cycles of loading to ensure the compaction to the expected level.

[0069] This application proposes to use rock as a material to simulate the strata, presenting an effect similar to the photoelastic phenomenon. Based on this idea, we have found a "digital speckle three-dimensional full-field strain" solution. In this solution, the stress field change is presented through strain, and research is carried out based on the sample surface, that is, it is used to verify the results of the two-dimensional finite element model. The specific technical principles are as follows: Simplify the three-dimensional ground stress field into a plane strain problem, that is, a two-dimensional plane strain finite element analysis. The experiment is designed according to the surface photography requirements, and the stress state is a plane stress problem. It should be noted here that since the embodiment of the present application studies the plane stress / strain distribution law of the stress field under small deformation conditions, without doing quantitative calculations and only conducting distribution law analysis, it is assumed that the numerical simulation plane strain problem and the experimental plane stress problem are equivalent.

[0070] This experimental system and method uses the principle of digital image correlation (DIC) to collect images through two industrial cameras, capture the surface features of the specimen before and after deformation, identify the changes in the surface features of the object to be tested, and then use three-dimensional reconstruction and digital image correlation algorithms to obtain the corresponding coordinate changes of each pixel in the image, thereby calculating the 3D displacement field, 3D strain field and 3D deformation field data in the process, and then adjusting and optimizing the digital modeling design method, obtaining the optimal modeling method and promoting it in three-dimensional modeling, and understanding the disturbance law of faults on ground stress.

[0071] Example 2

[0072] like Figure 6 As shown, an embodiment of the present application provides a physical simulation method for fault stress disturbance, comprising the following steps, S1: obtaining 3D displacement field, 3D strain field and 3D deformation field data of the object to be tested during loading through three-dimensional reconstruction and digital image correlation algorithm; S2: adjusting the digital modeling design method according to the above-mentioned 3D displacement field, the above-mentioned 3D strain field and the above-mentioned 3D deformation field data to obtain the optimal modeling method.

[0073] The above-mentioned method for simulating the physical disturbance of fault stress comprises the following steps: S3: applying the above-mentioned optimal modeling method to three-dimensional modeling to obtain the disturbance law of the fault on the ground stress.

[0074] Before implementing step S1, the in-situ stress of the object to be tested during loading is simulated; the surface features of the object to be tested before and after loading and deformation are collected, and the changes in the surface features of the object to be tested are identified.

[0075] The principle of the embodiment of the present application is the same as that of Embodiment 1, and no repetitive description is required here.

[0076] In summary, the embodiment of the present application utilizes the principle of digital image correlation (DIC), collects images through two industrial cameras, captures surface features of the specimen before and after deformation, identifies changes in surface features of the object to be tested, and then obtains the corresponding coordinate changes of each pixel of the image through three-dimensional reconstruction and digital image correlation algorithm, thereby calculating the 3D displacement field, 3D strain field and 3D deformation field data in the process, and then adjusting and optimizing the digital modeling design method, so as to obtain the optimal modeling method and promote its application in three-dimensional modeling, and find out the disturbance law of faults on ground stress.

[0077] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of 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 fault stress disturbance physical simulation system, characterized in that: include, Strain calculation module: used to calculate the 3D displacement field, 3D strain field and 3D deformation field data of the object under test during loading by using 3D reconstruction and digital image correlation algorithm to change the surface features of the object under test; Model optimization module: used to adjust the digital modeling design method according to the 3D displacement field, the 3D strain field and the 3D deformation field data to obtain the optimal modeling method.

2. A fault stress disturbance physical simulation system according to claim 1, characterized in that: It includes a model application module; the model application module is used to apply the optimal modeling method to three-dimensional modeling to obtain the disturbance law of fault on ground stress.

3. A fault stress disturbance physical simulation system according to claim 1, characterized in that: It includes a stress implementation system and a deformation numerical monitoring system; the stress implementation system is used to simulate the in-situ ground stress of the object to be tested during the loading process; The deformation digitization monitoring system is used to collect digital speckle images of the object to be measured before and after loading and deformation through the stress implementation system, and identify surface feature changes through the digital speckle images for calculation by the strain calculation module.

4. A fault stress disturbance physical simulation system according to claim 3, characterized in that: The stress implementation system includes a stress controller, a hydraulic station and a hydraulic loading system. The hydraulic station controls the hydraulic loading system through the stress controller to generate in-situ stress on the object to be tested.

5. A fault stress disturbance physical simulation system according to claim 3, characterized in that: The deformation digitization monitoring system comprises a light source, at least one industrial camera, a deformation analysis processing station and a monitoring controller; the light source is used as a digital speckle of the object to be measured; at least one industrial camera is used to obtain a digital speckle image of the surface of the object to be measured before and after deformation; The deformation analysis and processing station is used to identify surface feature changes of the object to be measured based on the digital speckle image; The monitoring controller is used to control the light source, at least one of the industrial cameras and the deformation analysis processing station respectively.

6. A fault stress disturbance physical simulation system according to claim 5, characterized in that: The resolution of at least one of the industrial cameras is 12 million at 30fps, the strain measurement accuracy of the deformation analysis processing station is 0.002%, and the maximum strain range of the deformation analysis processing station is 2000%.

7. A fault stress disturbance physical simulation system according to claim 3, characterized in that: The deformation numerical monitoring system adopts a digital image correlation method to perform quantitative analysis on full-field displacement and strain.

8. A fault stress disturbance physical simulation system according to claim 7, characterized in that: The digital image correlation method comprises the following steps: continuously dividing the speckle image of the object surface before deformation into a plurality of sub-areas of the same size as correlation areas, using the center points of the correlation areas as points to be measured, matching the divided correlation areas with the speckle image of the object surface after deformation to obtain the image coordinates of the corresponding image sub-areas and the center points of the sub-areas, calculating the displacement of the points to be measured, and obtaining the strain information through numerical difference calculation.

9. A fault stress disturbance physical simulation system according to claim 4, characterized in that: The equipment parameter configuration of the hydraulic station includes a test space net width of ≥500, a test force of 0 to 1000 kN, a piston displacement of 100 mm, and control parameters including force and displacement.

10. The fault stress disturbance physical simulation system according to claim 1, characterized in that: The object to be tested is a core or a core simulation sample corresponding to the formation rock mass.

11. A fault stress disturbance physical simulation system according to claim 10, characterized in that: The object to be measured is a cube with a size of 50 mm to 150 mm.

12. A fault stress disturbance physical simulation method, characterized in that: The following steps are included: S1: The surface feature changes of the image of the object to be tested are calculated by three-dimensional reconstruction and digital image correlation algorithm to obtain the 3D displacement field, 3D strain field and 3D deformation field data of the object to be tested during the loading process; S2: adjusting the digital modeling design method according to the 3D displacement field, the 3D strain field and the 3D deformation field data to obtain an optimal modeling method.

13. A fault stress disturbance physical simulation method according to claim 12, characterized in that: The method comprises the following steps: S3: applying the optimal modeling method to three-dimensional modeling to obtain the disturbance law of the fault on the ground stress.

14. A fault stress disturbance physical simulation method according to claim 12, characterized in that: The method comprises the following steps: before implementing step S1, simulating the in-situ stress of the object to be tested during loading; collecting the surface features of the object to be tested before and after loading and deformation, and identifying the changes in the surface features of the object to be tested.

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