In-situ measurement method and system for true triaxial hydraulic fracturing crack aperture

Abstract

The present invention provides an in-situ measurement method for true triaxial hydraulic fracturing crack aperture based on three-dimensional scanning, comprising: performing a hydraulic fracturing test on a prepared test specimen using a true triaxial hydraulic fracturing experimental system; removing residual acid and residue from the surface of the test specimen after the hydraulic fracturing test; scanning the test specimen using a three-dimensional scanner to construct a three-dimensional image framework point of the test specimen; using image processing software to form a framework image data file of the test specimen from the three-dimensional image framework point; separating the test specimen along the acid injection direction of the wellbore, and using a three-dimensional scanner to perform block image scanning to obtain a block image data file; again using the image processing software to import the block image data file into the framework image data file to form a three-dimensional image data file of the test specimen with embedded acidized cracks; and using the image processing software to perform cross-section processing on the three-dimensional image data file according to the needs of in-situ crack aperture measurement to obtain the acidized crack aperture.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas reservoir transformation effect evaluation, and in particular to an in-situ measurement method for true triaxial hydraulic fracturing crack aperture based on three-dimensional scanning and a true triaxial hydraulic fracturing experimental system. Background Art

[0002] Oil and gas reservoirs often coexist with dense rock formations, characterized by poor permeability, small pore throats, high capillary pressure, and strong heterogeneity. These reservoirs require hydraulic fracturing or acid fracturing to improve their conductivity. Post-fracturing seepage is a common microscopic flow phenomenon in nature, specifically the flow of fluid within pore structures. Permeability is a key parameter for evaluating reservoir permeability, and post-fracturing fracture aperture is directly related to permeability. Fracture width provides a direct reflection of fracture aperture, and its size is closely related to factors such as water and acid injection pressure, viscosity, displacement, and the stress environment. Fracture aperture can be used to evaluate fracturing effectiveness.

[0003] Traditional fracture characterization research methods include: (1) integrating the ground stress environment, rock parameters, fracturing media and injection parameters into theoretical fracture models or numerical simulation models to predict and calculate the expansion characteristics of fractures and analyze the laws of fracture expansion and rupture. However, due to the influence of natural characteristics such as rock heterogeneity and bedding differences, the errors often generated are large and the scope of application of the model is small; (2) With the development of science and technology, the maturity of technologies such as acoustic emission, CT scanning and 3D imaging has also been widely used in the study of fracture morphology. To a certain extent, the microporous fracture structure and size inside the rock are observed more clearly, which greatly helps researchers to extend the research scale. However, the above methods need to process the sample size and shape during application, and the test process has high requirements, so the accuracy of the test results is not ideal. The biggest obstacle is that it is impossible to directly obtain the original fracture parameters at a specific location.

[0004] As 3D scanning technology has shifted from industrial component processing to rock scanning, it has been widely used in rock property and structural research experiments. Its high precision and non-destructive nature can help scientific and technological workers capture the spatial geometric distribution characteristics of pore fractures on the surface and inside the rocks of various oil and gas reservoirs, and achieve the determination of permeability and the analysis of pore fracture structure characteristics and mineral composition. At the same time, with the help of load-applying devices, it can also study the evolution of surface cracks. In terms of crack aperture measurement, 3D scanning technology mainly focuses on the measurement of lining joint widths between tunnel rock blocks and other surface cracks such as bridges, railways, highways, and buildings. In rock mechanics, through special processing of the lens, it can also measure the surface cracks of some pressurized and heated specimens, but it cannot achieve the measurement of in-situ cracks inside the rock. Therefore, in order to further give play to the advantages of three-dimensional scanning technology and the means of expanding fracture measurement, combined with the true triaxial hydraulic fracturing experimental device to simulate reservoir fracturing and permeability enhancement experiments, in order to avoid the problem of violent destruction and separation of rock samples after the experiment, which may cause dislocation of fractures or increase the original width of fractures, to achieve the description of the in-situ fracture distribution inside the rock specimens and effectively quantitatively evaluate the effect of fracturing reservoir transformation, it is necessary to further improve and develop the existing technology. Summary of the Invention

[0005] The purpose of the embodiments of the present invention is to provide an in-situ measurement method for true triaxial hydraulic fracturing crack aperture based on three-dimensional scanning and a true triaxial hydraulic fracturing experimental system.

[0006] To achieve the above objectives, the present invention provides, in a first aspect, an in-situ method for measuring the aperture of a true triaxial hydraulic fracturing fracture based on three-dimensional scanning, comprising:

[0007] Conducting hydraulic fracturing tests on the prepared test specimens using a true triaxial hydraulic fracturing test system, wherein the test specimens can simulate actual reservoir geological characteristics;

[0008] cleaning residual acid and residue on the surface of the test specimen after the hydraulic fracturing test;

[0009] Scanning the test specimen with a three-dimensional scanner to construct a three-dimensional image framework of the test specimen, wherein the framework marking points are arranged on the surface of the test specimen before conducting a hydraulic fracturing test or after cleaning residual acid and residue;

[0010] Using image processing software to transform the three-dimensional image framework points into a framework image data file of the test specimen;

[0011] The test specimen is separated along the acid injection direction of the wellbore, and a block image is scanned using a three-dimensional scanner to obtain a block image data file;

[0012] Using the image processing software again, the block image data file is imported into the frame image data file to form a three-dimensional image data file of the test specimen with embedded acidized cracks;

[0013] According to the needs of in-situ fracture aperture measurement, the image processing software is used to perform cross-section processing on the three-dimensional image data file to obtain the acidizing fracture aperture.

[0014] In an embodiment of the present invention, the test specimen is a 300mm×300mm×300mm physical model cube; a geological structure is added inside the test specimen, and the geological structure includes at least one of a natural fracture, a fault, and a cave; and the hydraulic fracturing test uses at least one of gel acid, autogenous acid, solid acid, and water as the fracturing medium.

[0015] In an embodiment of the present invention, the true triaxial hydraulic fracturing experimental system is configured to simulate any three-dimensional original in-situ stress condition within the range of 0-100 MPa, and the experimental stress loading parameters are determined according to the in-situ stress environment of the target reservoir and in combination with similarity criteria.

[0016] In an embodiment of the present invention, the step of removing residual acid and residue from the surface of the test specimen after the hydraulic fracturing test comprises:

[0017] Residual acid on the surface of the test specimen and the simulated wellbore is removed, and residue on the surface of the test specimen is removed.

[0018] In an embodiment of the present invention, the frame marking points are evenly arranged on the surface of the test specimen.

[0019] In an embodiment of the present invention, the number of the framework marking points is determined according to the surface area of the test specimen, and there are at least three framework marking points within the three-dimensional scanning focal area.

[0020] In an embodiment of the present invention, the image processing software is Geomagic Studio image processing software, and the step of using the image processing software to transform the three-dimensional image framework points into a framework image data file of the test specimen includes:

[0021] The Geomagic Studio image processing software is used to merge all the framework point files of the test specimen obtained by scanning with the three-dimensional scanner into the framework image data file.

[0022] In the embodiment of the present invention, the wellbore acid injection direction is the main fracture development direction.

[0023] In an embodiment of the present invention, the image processing software is used to perform cross-section processing on the three-dimensional image data file according to the in-situ fracture aperture measurement requirements to obtain the acidizing fracture aperture, including:

[0024] Dividing the three-dimensional image data file into plane graphics at specific positions through different horizontal sections to form a crack profile;

[0025] The fracture profile is measured to obtain the acidized fracture aperture.

[0026] A second aspect of the present invention provides a true triaxial hydraulic fracturing test system, which is applied to the above-mentioned in-situ determination method of true triaxial hydraulic fracturing crack aperture based on three-dimensional scanning. The true triaxial hydraulic fracturing test system comprises:

[0027] True triaxial hydraulic pressure chamber, used to place test specimens;

[0028] A three-axis stress loading pump is used to apply pressure to the true triaxial hydraulic pressure chamber;

[0029] Fracturing fluid injection pump, used to inject fracturing medium into the true triaxial hydraulic pressure chamber;

[0030] The data monitoring and control device is configured to:

[0031] Outputting a first control command to the true triaxial hydraulic pressure chamber to control the three-axis stress loading pump to apply pressure to the true triaxial hydraulic pressure chamber;

[0032] outputting a second control command to the fracturing fluid injection pump to control the fracturing fluid injection pump to inject fracturing medium into the true triaxial hydraulic pressure chamber;

[0033] Acquire monitoring data from a true triaxial hydraulic pressure chamber.

[0034] The embodiments of the present invention have the following beneficial effects:

[0035] (1) The in-situ measurement method of true triaxial hydraulic fracturing based on three-dimensional scanning provided by the embodiment of the present invention can restore the extension of the cracks inside the rock and quantitatively characterize it in numerical form;

[0036] (2) By adjusting the position and number of the frame marking points, the extension range of a specific crack in a specific area of the rock sample can be obtained;

[0037] (3) At the same time, it avoids errors such as crack dislocation and increased crack opening caused by violent destruction of rock samples, ensuring the objectivity and accuracy of the measurement results. It can be widely used in the study of spatial distribution characteristics of laboratory core cracks.

[0038] Other features and advantages of the embodiments of the present invention will be described in detail in the subsequent detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the following detailed description, they are used to explain the embodiments of the present invention, but do not constitute a limitation of the embodiments of the present invention. In the accompanying drawings:

[0040] Figure 1 The figure schematically shows a flow chart of an in-situ method for measuring the aperture of a true triaxial hydraulic fracturing fracture based on three-dimensional scanning according to an embodiment of the present invention;

[0041] Figure 2 Schematically shows a structural block diagram of a true triaxial hydraulic fracturing device according to an embodiment of the present invention;

[0042] Figure 3 A schematic diagram of a rock sample according to an embodiment of the present invention is shown;

[0043] Figure 4 A schematic diagram of the arrangement of marker points in a three-dimensional scanning framework according to an embodiment of the present invention is shown, wherein Figure 4 (Left) shows the distribution of the frame marking points on the specimen, Figure 4 (Middle) shows the positional relationship of the frame marking points on one surface of the specimen, and Figure 4 (right) shows an enlarged view of a local area on one surface of the specimen;

[0044] Figures 5A-5D The block scanning effect diagram according to the embodiment of the present invention is shown. Figure 5A The left fragment image is shown, Figure 5B The right split image is shown, Figure 5C The left lobed model is shown, and FIG5D shows the right lobed model;

[0045] Figure 6A and Figure 6B The block scanning and merging effect diagram according to an embodiment of the present invention is shown. Figure 6A shows an image of cement blocks, Figure 6B shows the model after the two fragments are aligned; and

[0046] Figures 7A-7C shows a cross-sectional crack measurement diagram according to an embodiment of the present invention, wherein Figure 7A shows a schematic diagram of using a boundary to cut the model, Figure 7B A cross-section line is shown, Figure 7C The crack widths at different points along the cross-section are shown.

[0047] Description of Reference Numerals

[0048] 101-Three-axis stress loading pump; 102-True triaxial hydraulic pressure chamber; 103-Fracturing fluid injection pump; 104-Data monitoring and control device; CMD out -output command; Fb-feedback result; 105-test specimen; 9-simulated wellbore; 10-fracturing crack. DETAILED DESCRIPTION

[0049] The following describes the specific implementation of the embodiment of the present invention in detail with reference to the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the embodiment of the present invention and is not used to limit the embodiment of the present invention.

[0050] The structures, proportions, sizes, etc. illustrated in the drawings in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the art. They are not intended to limit the conditions under which the present invention may be implemented and therefore have no substantive technical significance. Any structural modifications, changes in proportions, or adjustments in sizes shall still fall within the scope of the technical contents disclosed in the present invention without affecting the efficacy and objectives that can be achieved by the present invention.

[0051] Figure 1 The following schematically shows a flow chart of an in-situ method for measuring the aperture of a true triaxial hydraulic fracturing fracture based on three-dimensional scanning according to an embodiment of the present invention. Figure 1 As shown, in an embodiment of the present invention, the in-situ measurement method may include the following steps.

[0052] In step S101, a hydraulic fracturing test is performed on a prepared test specimen using a true triaxial hydraulic fracturing test system, wherein the test specimen can simulate actual reservoir geological characteristics.

[0053] Specifically, the test specimen (e.g., rock specimen) can be a large-scale model cube of 300 mm × 300 mm × 300 mm. The true triaxial hydraulic fracturing test system can use the existing technology or the Figure 2 A true triaxial hydraulic fracturing test system according to an embodiment of the present invention is shown. Figure 2 The true triaxial hydraulic fracturing test system shown is described further below. Geological structures can be added to the test specimen. Examples of these structures include, but are not limited to, natural fractures, faults, and caves. True triaxial hydraulic fracturing tests can use gelled acid, autogenous acid, solid acid, and water as the fracturing medium.

[0054] True triaxial hydraulic fracturing experiments can simulate any three-dimensional original in-situ stress within the 0-100 MPa range. The experimental stress loading parameters are determined based on the target reservoir's in-situ stress environment and incorporating similarity criteria. The preferred fracturing medium for true triaxial hydraulic fracturing experiments is the actual acid used in field operations. If this acid cannot be mailed, laboratory preparation is considered.

[0055] In step S102, residual acid and residue on the surface of the test specimen after the hydraulic fracturing test are removed.

[0056] Specifically, cleaning residual acid and residue from the surface of the test specimen after the hydraulic fracturing test may include: cleaning residual acid from the surface of the test specimen and the simulated wellbore, and cleaning residue from the surface of the test specimen. This prevents the acid and residue from affecting the accuracy of scanning and experimental equipment, and creates a clean environment for arranging marking points.

[0057] In step S103, the test specimen is scanned by a 3D scanner to construct 3D image framework points of the test specimen, wherein framework marking points are arranged on the surface of the test specimen before conducting a hydraulic fracturing test or after cleaning residual acid and residue.

[0058] Wherein, the frame marking points are arranged evenly on the surface of the test specimen.

[0059] The number of the frame marking points is determined according to the surface area of the test specimen, and there are at least three frame marking points within the three-dimensional scanning focus area.

[0060] Specifically, the three-dimensional image frame points of the specimen are constructed with the help of a three-dimensional scanner. Arranging the frame marking points evenly on the surface of the test specimen is the basic key step for the entire fracture opening. Combined with the scanning accuracy requirements, the number and position of the marking points are determined according to the size of the rock specimen. It is necessary to ensure that there are more than three marking points within the three-dimensional scanning focus area. The optimal distribution should be as follows: Figure 4 (middle)( Figure 4 (In the middle, the horizontal axis numbers 1, 2, 3, ...i and the vertical axis numbers 1, 2, 3, ...n represent the distribution of the marking points on the specimen surface). As shown in FIG, the outer edge of each marking point should be 1 unit of marking point radius (r) away from each side (l or h) of the rock specimen, and each marking point should be 2 units of marking point radius (2r) away from each marking point in the horizontal or vertical direction.

[0061] In step S104, image processing software is used to convert the three-dimensional image framework points into a framework image data file of the test specimen.

[0062] Specifically, the image processing software may be Geomagic Studio image processing software, and the step of using the image processing software to transform the three-dimensional image framework points into a framework image data file of the test specimen includes:

[0063] The Geomagic Studio image processing software is used to merge all the frame point files of the test specimen obtained by scanning with the three-dimensional scanner into the frame image data file FrameM.

[0064] In step S105 , the test specimen is separated along the acid injection direction of the wellbore, and a three-dimensional scanner is used to perform block image scanning to obtain block image data files.

[0065] Specifically, the complete specimen can be separated along the acid injection direction of the wellbore to observe the acid fracturing cracks and the distribution of the acid solution. At the same time, a three-dimensional scanner is used to perform block image scanning to obtain the block image data file BlockN. i (i=1,2,3……, i is equal to the number of test piece blocks).

[0066] The direction of acid injection in the wellbore is generally the direction of development of the main fracture. It is easier to separate the specimens along this direction, and the fracture surface and acid distribution are clearer.

[0067] Use a 3D scanner to scan block images, and the data file type is BlockN i .AC, the number of blocks of the specimen determines the number of block scan images, and each block image file is merged into BlockN i .stl type, take the complete rock specimen divided into two pieces as an example and scan them, the scanning results are as follows Figures 5A-5D shown.

[0068] In step S106, the image processing software is used again to import the block image data file into the frame image data file to form a three-dimensional image data file MN of the test specimen with embedded acidizing cracks.

[0069] Specifically, Geomagic Studio image processing software is used again to import the block image data file BlockNi.stl into the frame image FrameM.frm to form a complete specimen three-dimensional image data file MN.stl with embedded acidizing cracks. The effect is as follows: Figure 6A and Figure 6B shown.

[0070] In step S107, according to the requirements of in-situ fracture aperture measurement, the image processing software is used to perform cross-section processing on the three-dimensional image data file MN to obtain the acidizing fracture aperture.

[0071] Specifically, refer to Figures 7A-7C According to the needs of in-situ fracture aperture measurement, the data file MN is processed by Geomagic Studio image processing software. The fracture width at different positions corresponding to each cross section is the fracture development under this true triaxial hydraulic fracturing, and the acidized fracture aperture is obtained. The measurement results are as follows: Figure 7C As shown in the figure, the crack widths from left to right are 0.08mm, 0.16mm, 0.45mm, 0.24mm, 0.46mm, and 0.31mm. Figure 7C It can be roughly observed that the width of the crack gradually decreases as it extends outward from the center of the simulated wellbore, consistent with the basic law of crack expansion in acid fracturing experiments. However, as the crack expands to the right, it increases from 0.24mm to 0.46mm, indicating that acid has accumulated at this location, the degree of acid corrosion is relatively severe, or there is an original crack of a certain width.

[0072] In the embodiment of the present invention, the crack profile is an in-situ crack profile of the specimen, which avoids the influence of crack expansion and dislocation caused by artificial separation of the specimen.

[0073] Figure 2 The structural block diagram of the true triaxial hydraulic fracturing device according to an embodiment of the present invention is schematically shown. Figure 2 As shown, the true triaxial hydraulic fracturing device can be applied to the in-situ determination method of true triaxial hydraulic fracturing crack aperture based on three-dimensional scanning in the above embodiment. The true triaxial hydraulic fracturing device may include:

[0074] a true triaxial hydraulic pressure chamber 102 for placing a test specimen 105 (e.g., a rock specimen);

[0075] The three-dimensional stress loading pump 101 is used to apply pressure to the test specimen of the true triaxial hydraulic pressure chamber to simulate any three-dimensional original ground stress condition in the range of 0-100 MPa. The three-dimensional stress loading pump can apply pressure to the true triaxial hydraulic pressure chamber from three directions, for example Figure 2 δ1, δ2, δ3 as shown in . Figure 2 As shown, the true triaxial hydraulic pressure chamber is provided with stress loading devices in three directions (e.g., up, left, and right), and a three-way stress loading pump can drive the stress loading device to apply three-way stress to the test specimen of the true triaxial hydraulic pressure chamber.

[0076] The fracturing fluid injection pump 103 is used to inject a fracturing medium, such as gel acid, autogenous acid, solid acid, and water, into the true triaxial hydraulic pressure chamber. For example, the top of the true triaxial hydraulic pressure chamber may have an inlet, through which the fracturing fluid injection pump injects the fracturing medium into the true triaxial hydraulic pressure chamber.

[0077] The data monitoring and control device 104 is configured to:

[0078] Output the first control command (e.g. CMD out ) to control the triaxial stress loading pump to apply pressure to the true triaxial hydraulic pressure chamber;

[0079] Output a second control command (e.g. CMD out ) to control the fracturing fluid injection pump to inject fracturing medium into the true triaxial hydraulic pressure chamber;

[0080] Monitoring data (eg, feedback result Fb) is acquired from the true triaxial hydraulic pressure chamber. Examples of the monitoring data include, for example, the pressure applied in the true triaxial hydraulic pressure chamber.

[0081] After acidification or hydraulic testing of rock specimens using a true triaxial hydraulic fracturing device, cracks will form inside the specimens, but the specimens are intact. If you want to see the cracks inside the specimens, it is not feasible to use the existing CT scanning method because the specimens are large and CT scanning is not thorough. Therefore, the commonly used method is to break the specimen into two petals. However, the crack surface of each petal has roughness, so only the surface roughness can be known, and the width of the crack cannot be measured. The method of the embodiment of the present invention can solve this problem well.

[0082] In summary, the solutions of the embodiments of the present invention have the following beneficial effects:

[0083] (1) The in-situ measurement method of true triaxial hydraulic fracturing based on three-dimensional scanning provided by the embodiment of the present invention can restore the extension of the cracks inside the rock and quantitatively characterize it in numerical form;

[0084] (2) By adjusting the position and number of the frame marking points, the extension range of a specific crack in a specific area of the rock sample can be obtained;

[0085] (3) At the same time, it avoids errors such as crack dislocation and increased crack opening caused by violent destruction of rock samples, ensuring the objectivity and accuracy of the measurement results. It can be widely used in the study of spatial distribution characteristics of laboratory core cracks.

[0086] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0087] The above are merely embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. An in-situ measurement method for true triaxial hydraulic fracturing crack aperture based on three-dimensional scanning, characterized in that: include: Conducting hydraulic fracturing tests on the prepared test specimens using a true triaxial hydraulic fracturing test system, wherein the test specimens can simulate actual reservoir geological characteristics; Cleaning the residual acid on the surface of the test specimen and the simulated wellbore, and cleaning the residue on the surface of the test specimen; Scanning the test specimen with a three-dimensional scanner to construct a three-dimensional image frame of the test specimen, wherein frame marking points are arranged on the surface of the test specimen before conducting a hydraulic fracturing test or after removing residual acid and residue, the frame marking points are evenly arranged on the surface of the test specimen, the number of the frame marking points is determined according to the surface area of the test specimen, and there are at least three frame marking points within the three-dimensional scanning focal area, the outer edge of each frame marking point is 1 unit of marking point radius from each side of the test specimen, and each frame marking point is 2 units of marking point radius apart in the horizontal or vertical direction; Using image processing software to transform the three-dimensional image framework points into a framework image data file of the test specimen; The test specimen is separated along the acid injection direction of the wellbore, and a block image is scanned using a three-dimensional scanner to obtain a block image data file; Using the image processing software again, the block image data file is imported into the frame image data file to form a three-dimensional image data file of the test specimen with embedded acidized cracks; as well as Dividing the three-dimensional image data file into plane graphics at specific positions through different horizontal sections to form a crack profile; The fracture profile is measured to obtain the acidized fracture aperture.

2. The in-situ measurement method according to claim 1, wherein The test specimen is a physical model cube with a size of 300mm×300mm×300mm; a geological structure is added inside the test specimen, and the geological structure includes at least one of natural fractures, faults and caves; the hydraulic fracturing test uses at least one of gel acid, autogenous acid, solid acid and water as the fracturing medium.

3. The in-situ measurement method according to claim 2, wherein The true triaxial hydraulic fracturing experimental system is configured to simulate any three-dimensional original in-situ stress condition within the range of 0-100 MPa, and the experimental stress loading parameters are determined according to the in-situ stress environment of the target reservoir and in combination with similarity criteria.

4. The in-situ measurement method according to claim 1, wherein The image processing software is Geomagic Studio image processing software, and the image processing software is used to form a frame image data file of the test specimen from the three-dimensional image framework points, including: The Geomagic Studio image processing software is used to merge all the framework point files of the test specimen obtained by scanning with the three-dimensional scanner into the framework image data file.

5. The in-situ measurement method according to claim 1, wherein The direction of acid injection in the wellbore is the direction of development of the main fractures.

6. A true triaxial hydraulic fracturing test system, characterized in that: The in-situ determination method of true triaxial hydraulic fracturing crack aperture based on three-dimensional scanning according to any one of claims 1 to 5 is applied, wherein the true triaxial hydraulic fracturing experimental system comprises: True triaxial hydraulic pressure chamber, used to place test specimens; A three-axis stress loading pump is used to apply pressure to the true triaxial hydraulic pressure chamber; Fracturing fluid injection pump, used to inject fracturing medium into the true triaxial hydraulic pressure chamber; The data monitoring and control device is configured to: Outputting a first control command to the true triaxial hydraulic pressure chamber to control the three-axis stress loading pump to apply pressure to the true triaxial hydraulic pressure chamber; outputting a second control command to the fracturing fluid injection pump to control the fracturing fluid injection pump to inject fracturing medium into the true triaxial hydraulic pressure chamber; Acquire monitoring data from a true triaxial hydraulic pressure chamber.

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