A method for three-dimensional stress inversion of optical fibers based on numerical simulation calibration
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-15
- Publication Date
- 2026-08-14
AI Technical Summary
然而，相关技术中的应力解算通常依赖基于均质各向同性、线弹性等理想假设的解析模型，难以纳入孔径偏差、胶结层厚度差异、材料参数离散等实际工况耦合影响，导致应力反演与实际偏差，尤其在主应力方向输出上更为敏感
[0016]本申请提供的基于数值模拟标定的光纤三维应力反演解算方法，构建待测岩体的三维耦合数值模型，并分别施加三个正应力分量和三个剪应力分量的单位载荷以确定测点应变分量，进而求解影响系数矩阵，使得实际工况中孔径偏差、胶结层厚度差异、材料弹性参数及粘结状态等复杂因素被系统纳入标定过程，避免了传统解析方法依赖理想均质假设导致的模型失配和系统误差，显著提高了不同工程条件下应力反演结果的准确性和一致性。基于影响系数矩阵反演求解三维应力张量并进一步计算主应力大小和主应力方向，实现了从实测应变到地应力成果的一体化自动解算，且利用光纤传感器获取实测应变向量，有效克服深孔环境中电磁干扰和长距离信号衰减问题。本申请可为围岩稳定性分析、支护参数优化和灾害风险评价提供了更准确、可复现的基础数据支撑。
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Abstract
Description
Technical Field
[0001] This application relates to the field of rock engineering technology, and in particular to a fiber optic three-dimensional stress inversion solution method based on numerical simulation calibration. Background Technology
[0002] With the rapid advancement of deep coal mining, deep-buried tunnels, and underground space development, engineering rock masses are gradually entering complex environments characterized by high ground stress and strong disturbance. The magnitude and principal stress direction of three-dimensional ground stress are key foundational data for surrounding rock stability analysis, support parameter optimization, and disaster risk assessment. Engineering sites are placing higher demands on the accuracy, stability, and efficiency of ground stress acquisition.
[0003] The borehole stress gauge method is widely used in deep engineering due to its potential for multi-point deployment and profiling measurements. This method involves cementing stress gauges within the borehole and using the strain response at multiple measuring points to infer the rock mass stress tensor. However, stress calculations in related technologies typically rely on analytical models based on ideal assumptions such as homogeneity, isotropy, and linear elasticity. This makes it difficult to incorporate the coupling effects of actual working conditions, such as borehole diameter deviations, cementation layer thickness differences, and material parameter discrepancies, leading to discrepancies between the stress inversion and actual values, especially sensitive to principal stress directions. Furthermore, the calculation coefficients are mostly fixed or empirical values, unable to adaptively update with changes in parameters such as borehole diameter, cementation layer, and stress gauge structure. This results in increased errors and poor consistency of results when applied across different working conditions. Therefore, there is an urgent need for a robust inversion method that can adapt to various working conditions to meet the pressing requirements of deep engineering for accurate, stable, and engineering-adaptable geostress measurements. Summary of the Invention
[0004] This application aims to at least partially address one of the technical problems in the related art.
[0005] Therefore, the first aspect of this application proposes a method for three-dimensional stress inversion calculation of optical fibers based on numerical simulation calibration, comprising the following steps:
[0006] A three-dimensional coupled numerical model of the rock mass to be tested is constructed based on the working parameters of the target borehole and its stress gauge installation conditions. The three-dimensional coupled numerical model includes the rock mass, borehole, cemented layer and stress gauge structure. Multiple stress components are applied to the three-dimensional coupled numerical model, and the strain components at the measuring points on the stress gauge are determined each time a unit load is applied. The multiple stress components include three normal stress components and three shear stress components. Based on the unit load of the strain component and the plurality of stress components, the influence coefficient matrix is obtained. The influence coefficient matrix is used to characterize the linear mapping relationship between the stress component and the strain component. The measured strain vector at the measuring point on the rock mass to be tested is obtained by an optical fiber sensor set on the outer surface of the stress gauge; Based on the influence coefficient matrix and the measured strain vector, the three-dimensional stress tensor is solved by inversion. The magnitude and direction of the principal stresses of the rock mass under test are determined based on the three-dimensional stress tensor.
[0007] In some embodiments of this application, for a unit load of the normal stress component, a unit normal stress is applied to the outer boundary of the corresponding unit load direction in the three-dimensional coupled numerical model, and other boundary displacements are constrained; for a unit load of the shear stress component, a pair of shear stress unit loads are applied to the outer boundary of the three-dimensional coupled numerical model, and displacements in directions independent of shear are constrained.
[0008] In some embodiments of this application, determining the strain components at the measuring points on the stress gauge each time a unit load is applied includes: after applying a unit load of multiple stress components respectively, obtaining the displacement field of the three-dimensional coupled numerical model; determining the circumferential strain, axial strain, and shear component of the measuring point based on the displacement field; and determining the strain component of the corresponding measuring point based on the circumferential strain, the axial strain, and the shear component.
[0009] In some embodiments of this application, the strain component at the corresponding measuring point is determined using the following formula based on the circumferential strain, the axial strain, and the shear component:
[0010] in, The strain component is... The circumferential strain is described above. Let be the axial strain. The shear component, The angle between the measurement direction of the measuring point and the borehole axis direction.
[0011] In some embodiments of this application, the outer surface of the stress gauge is provided with multiple sets of the fiber optic sensors, each set including multiple measuring points in different directions.
[0012] In some embodiments of this application, the working condition parameters include rock mass geometry information, borehole geometry information, stress gauge structure information, cementation layer information, and mechanical parameters of the rock mass, cementation layer, and stress gauge materials.
[0013] In some embodiments of this application, the fiber optic sensor is a fiber Bragg grating sensor or a distributed fiber optic sensor. A second aspect of this application provides a fiber optic three-dimensional stress inversion solution device based on numerical simulation calibration, comprising: The modeling module is used to construct a three-dimensional coupled numerical model of the rock mass to be tested based on the working parameters of the target borehole and its stress gauge installation conditions. The three-dimensional coupled numerical model includes the rock mass, borehole, cemented layer and stress gauge structure. The unit load simulation module is used to apply a unit load of multiple stress components to the three-dimensional coupled numerical model, and to determine the strain components at the measuring points on the stress gauge each time a unit load is applied. The multiple stress components include three normal stress components and three shear stress components. The solution module is used to solve for the influence coefficient matrix based on the unit load of the strain component and the plurality of stress components. The influence coefficient matrix is used to characterize the linear mapping relationship between the stress component and the strain component. The strain measurement module is used to acquire the measured strain vector at the measuring point on the rock mass to be tested through an optical fiber sensor set on the outer surface of the stress gauge; The first determining module is used to invert and solve the three-dimensional stress tensor based on the influence coefficient matrix and the measured strain vector. The second determining module is used to determine the magnitude and direction of the principal stresses of the rock mass to be tested based on the three-dimensional stress tensor.
[0014] A third aspect of this application provides an electronic device, including: a processor, and a memory communicatively connected to the processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory to implement the method described in the first aspect above.
[0015] A fourth aspect of this application provides a computer-readable storage medium, characterized in that the computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method described in the first aspect above.
[0016] This application provides a fiber-optic three-dimensional stress inversion solution method based on numerical simulation calibration. It constructs a three-dimensional coupled numerical model of the rock mass under test and applies unit loads of three normal stress components and three shear stress components to determine the strain components at the measuring points. Then, it solves the influence coefficient matrix, systematically incorporating complex factors such as borehole diameter deviation, cement layer thickness differences, material elastic parameters, and bonding state into the calibration process. This avoids model mismatch and systematic errors caused by the assumption of ideal homogeneity in traditional analytical methods, significantly improving the accuracy and consistency of stress inversion results under different engineering conditions. Based on the influence coefficient matrix, the method inverts and solves the three-dimensional stress tensor, further calculating the magnitude and direction of the principal stresses. This achieves integrated automatic calculation from measured strain to in-situ stress results. Furthermore, it utilizes fiber optic sensors to acquire the measured strain vector, effectively overcoming electromagnetic interference and long-distance signal attenuation problems in deep borehole environments. This application provides more accurate and reproducible basic data support for surrounding rock stability analysis, support parameter optimization, and disaster risk assessment.
[0017] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description
[0018] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein: Figure 1 A flowchart illustrating a fiber optic three-dimensional stress inversion solution method based on numerical simulation calibration, provided for an embodiment of this application; Figure 2 A schematic diagram of a three-dimensional coupled numerical model provided in an embodiment of this application; Figure 3 A schematic diagram of the distribution of stress gauge measuring points provided in an embodiment of this application; Figure 4 A schematic diagram illustrating the application of a unit load to each of the six stress components, provided for an embodiment of this application; Figure 5 A schematic diagram illustrating the method of obtaining an influence coefficient matrix by splicing strain components, as provided in an embodiment of this application; Figure 6 This is a schematic diagram of a fiber optic three-dimensional stress inversion solution device based on numerical simulation calibration, provided in an embodiment of this application. Detailed Implementation
[0019] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.
[0020] Specifically, the following describes an embodiment of the fiber optic three-dimensional stress inversion solution method based on numerical simulation calibration, with reference to the accompanying drawings.
[0021] Figure 1 This is a flowchart illustrating a method for solving three-dimensional stress inversion in optical fibers based on numerical simulation calibration, provided as an embodiment of this application. Figure 1 As shown, the fiber optic three-dimensional stress inversion solution method based on numerical simulation calibration may include the following steps: Step 101: Construct a three-dimensional coupled numerical model of the rock mass to be tested based on the working parameters of the target borehole and its stress gauge installation conditions. The three-dimensional coupled numerical model includes the rock mass, borehole, cemented layer and stress gauge structure.
[0022] As an example, operating parameters may include rock mass geometry information (size, coordinate system definition, size can be selected as 3-5 times the borehole radius), borehole geometry information (borehole diameter, borehole section, borehole direction and coordinate system definition), stress gauge structural information (shape, thickness, measuring point arrangement and numbering rules), cemented layer information (thickness and range), and mechanical parameters of rock mass, cemented layer and stress gauge materials (which can be given by experiments, core sampling tests, empirical values or design parameters).
[0023] Figure 2 This is a schematic diagram of a three-dimensional coupled numerical model provided in an embodiment of this application. The three-dimensional coupled numerical model, constructed based on working parameters, includes an external rock mass domain containing boreholes, a cemented layer, a stress gauge structure, and the corresponding positions / paths of measuring points within the model. Mesh generation and contact / bonding relationship settings are completed to ensure that stress transfer and strain output conform to the actual assembly and bonding state. It should be noted that the number and distribution of the stress gauge measuring points in the three-dimensional coupled numerical model are the same as the measuring points in the actual working scenario of the rock mass under test.
[0024] To address the unavoidable physical uncertainties and measurement disturbances in practical engineering, some embodiments of this application employ a redundant layout for the measurement points to form overdetermined equations. In one implementation, multiple sets of fiber optic sensors are disposed on the outer surface of the stress gauge, each set including multiple measurement points in different directions. Figure 3 This is a schematic diagram of the distribution of stress gauge measuring points provided in an embodiment of this application. Figure 3As shown, at least three sets of fiber optic sensors are evenly spaced along the circumference of the outer surface of the stress gauge cylinder, each set including at least three measuring points. As an example, three sets of fiber optic sensors can be wound or pasted at 120° intervals around the outer surface of the stress gauge cylinder. The measurement direction of the measuring points in each set of fiber optic sensors... φ The axial spacing of the sensors can be minimized, with the angles being 0°, 45°, and 90° relative to the borehole axis.
[0025] Step 102: Apply unit loads of multiple stress components to the three-dimensional coupled numerical model, and determine the strain components at the measuring points on the stress gauge each time a unit load is applied. The multiple stress components include three normal stress components and three shear stress components.
[0026] In this embodiment, the three-dimensional stress tensor is decomposed into six independent stress components, constructing six sets of "unit stress" calibration conditions, and the unit load of the three normal stress components: , , The unit load for the three shear stress components: , , .
[0027] Figure 4 This diagram illustrates the application of a unit load to each of the six stress components, as provided in an embodiment of this application. In some embodiments of this application, the unit load condition for each stress component can adopt a uniform and reproducible boundary application principle: For a unit load of normal stress component, a unit normal stress is applied to the outer boundary corresponding to the unit load direction in the three-dimensional coupled numerical model, and the displacements of other boundaries are constrained to ensure solution stability. For the unit load of the shear stress component, paired shear stress unit loads are applied to the outer boundary of the three-dimensional coupled numerical model, and displacements in directions independent of shear are constrained to ensure that the shear condition is pure and reproducible.
[0028] In one implementation, after applying unit loads with multiple stress components to the three-dimensional coupled numerical model, the displacement field of the model can be obtained, and the circumferential strain, axial strain, and shear components at the measuring points can be determined based on the displacement field. The strain components at the corresponding measuring points are then determined based on the circumferential strain, axial strain, and shear components. As an example, the circumferential strain, axial strain, and shear components can be described using cylindrical coordinates (r, θ, z). Circumferential strain : Describes the tension or compression of material along the borehole axis (Z-axis); Axial strain : Describes the tension or compression of material along the circumference of the borehole (θ angle direction); Shear component : Describes the shear strain of a unit cell along the axial direction (Z direction) on a plane (θ plane), reflecting the torsional tendency.
[0029] The strain components at the corresponding measuring point can be determined using the following formula:
[0030] in, For strain components, For circumferential strain, For axial strain, For shear components, The angle between the measuring direction of the measuring point and the borehole axis direction (i.e. Figure 3 (Measurement direction of the middle measuring point).
[0031] Step 103: Based on the unit load of the strain component and multiple stress components, the influence coefficient matrix is obtained. The influence coefficient matrix is used to characterize the linear mapping relationship between the stress component and the strain component.
[0032] The linear mapping relationship between stress components and strain components can be expressed as follows:
[0033] in, This is the influence coefficient matrix. For stress components, For strain components.
[0034] by Figure 3 For example, three sets of fiber optic sensors are set up, each set including three measurement points (a total of 9 measurement points). The measurement direction of the measurement points in each set of fiber optic sensors is... φ For directions at 0°, 45°, and 90° to the borehole axis, the linear mapping relationship between stress and strain components can be expanded as follows:
[0035] in, - This data represents the strain components collected at nine measuring points when a unit load of a certain stress component is applied to a three-dimensional coupled numerical model. The strain components are measured using the applied normal stress component. For example, , , , , , The values are [1, 0, 0, 0, 0, 0]. Therefore, after obtaining the stress components and strain components collected at each measuring point under each unit load, the influence coefficient matrix in the linear mapping relationship can be calculated. Since the stress component applied each time is a unit load, therefore... Figure 5 As shown, six loading conditions ( , , , , , The strain components are assembled column-wise to obtain the influence coefficient matrix. .
[0036] Step 104: Obtain the measured strain vector of the measuring point on the rock mass under test by using an optical fiber sensor set on the outer surface of the stress gauge.
[0037] Optionally, the fiber optic sensor can be a fiber Bragg grating sensor or a distributed fiber optic sensor. In one example, after acquiring the strain vector at the field measurement point using the fiber optic sensor (FBG wavelength drift or distributed strain signal), preprocessing such as temperature compensation and zero-point calibration (e.g., using a reference grating / same-hole temperature point / algorithm compensation) can be performed to obtain the measured strain vector. :
[0038] Step 105: Based on the influence coefficient matrix and the measured strain vector, the three-dimensional stress tensor is solved by inversion.
[0039] The three-dimensional stress tensor can be calculated using the following formula. :
[0040] in, .
[0041] Step 106: Determine the magnitude and direction of the principal stresses of the rock mass to be tested based on the three-dimensional stress tensor.
[0042] In some embodiments of this application, the three-dimensional principal stress in the geodetic coordinate system can be calculated using the following formula:
[0043] Among them, the three roots obtained by the above formula , and That is, the three-dimensional principal stress. J 1, J 2, J 3 can be calculated as follows:
[0044] Direction of principal stress l , m , n It can be calculated using the following formula:
[0045] By implementing the embodiments of this application, a three-dimensional coupled numerical model of the rock mass to be tested is constructed. Unit loads of three normal stress components and three shear stress components are applied to determine the strain components at the measuring points. The influence coefficient matrix is then solved, allowing complex factors such as borehole diameter deviation, cement layer thickness differences, material elastic parameters, and bonding state under actual working conditions to be systematically incorporated into the calibration process. This avoids model mismatch and systematic errors caused by the assumption of ideal homogeneity in traditional analytical methods, significantly improving the accuracy and consistency of stress inversion results under different engineering conditions. Based on the influence coefficient matrix, the three-dimensional stress tensor is solved by inversion, and the magnitude and direction of the principal stresses are further calculated, achieving integrated automatic calculation from measured strain to in-situ stress results. Furthermore, the use of fiber optic sensors to acquire the measured strain vector effectively overcomes electromagnetic interference and long-distance signal attenuation problems in deep borehole environments. This application provides more accurate and reproducible basic data support for surrounding rock stability analysis, support parameter optimization, and disaster risk assessment.
[0046] Figure 6 This is a schematic diagram of a fiber optic three-dimensional stress inversion solution device based on numerical simulation calibration, provided as an embodiment of this application. Figure 6 As shown, the fiber optic three-dimensional stress inversion solution device based on numerical simulation calibration may include: a modeling module 601, a unit load simulation module 602, a solution module 603, a strain measurement module 604, a first determination module 605, and a second determination module 606.
[0047] Modeling module 601 is used to construct a three-dimensional coupled numerical model of the rock mass to be tested based on the working parameters of the target borehole and its stress gauge installation conditions. The three-dimensional coupled numerical model includes the rock mass, borehole, cemented layer and stress gauge structure. The unit load simulation module 602 is used to apply a unit load of multiple stress components to the three-dimensional coupled numerical model, and to determine the strain components at the measuring points on the stress gauge when the unit load is applied each time. The multiple stress components include three normal stress components and three shear stress components. The solver module 603 is used to solve for the influence coefficient matrix based on the unit load of the strain component and multiple stress components. The influence coefficient matrix is used to characterize the linear mapping relationship between the stress component and the strain component. The strain measurement module 604 is used to acquire the measured strain vector of the measuring point on the rock mass to be measured through an optical fiber sensor set on the outer surface of the stress gauge; The first determining module 605 is used to invert and solve the three-dimensional stress tensor based on the influence coefficient matrix and the measured strain vector. The second determining module 606 is used to determine the magnitude and direction of the principal stresses of the rock mass to be tested based on the three-dimensional stress tensor.
[0048] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.
[0049] To implement the above embodiments, this application also proposes an electronic device, including: a processor and a memory communicatively connected to the processor; the memory stores computer execution instructions; the processor executes the computer execution instructions stored in the memory to implement the method provided in the foregoing embodiments.
[0050] To implement the above embodiments, this application also proposes a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the methods provided in the foregoing embodiments.
[0051] To implement the above embodiments, this application also proposes a computer program product, including a computer program that, when executed by a processor, implements the methods provided in the foregoing embodiments.
[0052] In the foregoing descriptions of the embodiments, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.
[0053] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0054] Any process or method description in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or more executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.
[0055] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically, for example, by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.
[0056] It should be understood that various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, multiple steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.
[0057] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.
[0058] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.
[0059] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.
Claims
1. A method for three-dimensional stress inversion calculation of optical fibers based on numerical simulation calibration, characterized in that, Includes the following steps: A three-dimensional coupled numerical model of the rock mass to be tested is constructed based on the working parameters of the target borehole and its stress gauge installation conditions. The three-dimensional coupled numerical model includes the rock mass, borehole, cemented layer and stress gauge structure. Multiple stress components are applied to the three-dimensional coupled numerical model, and the strain components at the measuring points on the stress gauge are determined each time a unit load is applied. The multiple stress components include three normal stress components and three shear stress components. Based on the unit load of the strain component and the plurality of stress components, the influence coefficient matrix is obtained. The influence coefficient matrix is used to characterize the linear mapping relationship between the stress component and the strain component. The measured strain vector at the measuring point on the rock mass to be tested is obtained by an optical fiber sensor set on the outer surface of the stress gauge; Based on the influence coefficient matrix and the measured strain vector, the three-dimensional stress tensor is solved by inversion. The magnitude and direction of the principal stresses of the rock mass under test are determined based on the three-dimensional stress tensor.
2. The fiber optic three-dimensional stress inversion solution method based on numerical simulation calibration according to claim 1, characterized in that, For the unit load of the normal stress component, a unit normal stress is applied to the outer boundary corresponding to the unit load direction in the three-dimensional coupled numerical model, and other boundary displacements are constrained. For the unit load of the shear stress component, a pair of shear stress unit loads are applied to the outer boundary of the three-dimensional coupled numerical model, and displacements in directions independent of shear are constrained.
3. The fiber optic three-dimensional stress inversion solution method based on numerical simulation calibration according to claim 1, characterized in that, The determination of the strain components at the measuring points on the stress gauge for each applied unit load includes: After applying unit loads of multiple stress components, the displacement field of the three-dimensional coupled numerical model is obtained. The circumferential strain, axial strain, and shear component of the measuring point are determined based on the displacement field. The strain component at the corresponding measuring point is determined based on the circumferential strain, the axial strain, and the shear component.
4. The fiber optic three-dimensional stress inversion solution method based on numerical simulation calibration according to claim 3, characterized in that, Based on the circumferential strain, the axial strain, and the shear component, the strain component at the corresponding measuring point is determined using the following formula: in, The strain component is... The circumferential strain is described above. Let be the axial strain. The shear component, The angle between the measurement direction of the measuring point and the borehole axis direction.
5. The fiber optic three-dimensional stress inversion solution method based on numerical simulation calibration according to claim 1, characterized in that, The outer surface of the stress gauge is provided with multiple sets of fiber optic sensors, each set including multiple measuring points in different directions.
6. The fiber optic three-dimensional stress inversion solution method based on numerical simulation calibration according to claim 1, characterized in that, The operating parameters include rock mass geometry, borehole geometry, stress gauge structure, cementation layer information, and mechanical parameters of the rock mass, cementation layer, and stress gauge materials.
7. The fiber optic three-dimensional stress inversion solution method based on numerical simulation calibration according to claim 1, characterized in that, The fiber optic sensor is a fiber Bragg grating sensor or a distributed fiber optic sensor.
8. A fiber optic three-dimensional stress inversion solution device based on numerical simulation calibration, characterized in that, include: The modeling module is used to construct a three-dimensional coupled numerical model of the rock mass to be tested based on the working parameters of the target borehole and its stress gauge installation conditions. The three-dimensional coupled numerical model includes the rock mass, borehole, cemented layer and stress gauge structure. The unit load simulation module is used to apply a unit load of multiple stress components to the three-dimensional coupled numerical model, and to determine the strain components at the measuring points on the stress gauge each time a unit load is applied. The multiple stress components include three normal stress components and three shear stress components. The solution module is used to solve for the influence coefficient matrix based on the unit load of the strain component and the plurality of stress components. The influence coefficient matrix is used to characterize the linear mapping relationship between the stress component and the strain component. The strain measurement module is used to acquire the measured strain vector at the measuring point on the rock mass to be tested through an optical fiber sensor set on the outer surface of the stress gauge; The first determining module is used to invert and solve the three-dimensional stress tensor based on the influence coefficient matrix and the measured strain vector. The second determining module is used to determine the magnitude and direction of the principal stresses of the rock mass to be tested based on the three-dimensional stress tensor.
9. An electronic device, characterized in that, include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory to implement the method as described in any one of claims 1-7.
10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method as described in any one of claims 1-7.