CN-121977462-A - Coal rock mass tensile shear deformation decoupling monitoring method, system, equipment and medium based on generalized equivalent geometric model

CN121977462ACN 121977462 ACN121977462 ACN 121977462ACN-121977462-A

Abstract

The application discloses a coal rock mass tensile shear deformation decoupling monitoring method, a system, equipment and a medium based on a generalized equivalent geometric model, and relates to the field of coal rock mechanical monitoring; the method comprises the steps of obtaining a true dislocation displacement vector to be determined according to an initial length and a deformation length for any analysis unit, decomposing the true dislocation displacement vector to be determined into a projection component and an equivalent shear displacement along the axial direction of an optical fiber, forming an equivalent right-angled triangle model based on the initial length, the deformation length, the projection component and the equivalent shear displacement along the axial direction of the optical fiber, obtaining a pull-shear coupling equation based on the equivalent right-angled triangle model, and determining the equivalent axial strain and the equivalent shear displacement by adopting the pull-shear coupling equation based on the total axial strain of the optical fiber of the analysis unit. The application realizes the accurate decoupling of the complex pull-shear deformation field of the coal rock mass.

Inventors

MA SHUQI
XU XIANG
YUAN LIANG
CHEN JIANXING
LIU WEI
LI YANHUI
CHEN JIAZHENG
Yao Xiangchen

Assignees

安徽理工大学

Dates

Publication Date: 20260505
Application Date: 20251229

Claims (10)

1. A method for monitoring the decoupling of the tensile shear deformation of a coal rock mass based on a generalized equivalent geometric model, which is characterized in that a sensing optical cable containing an optical fiber is implanted in the coal rock mass, and the method comprises the following steps: After the coal rock mass is pulled, sheared and deformed, acquiring a Brillouin frequency shift signal of each analysis unit, and obtaining the total axial strain of an optical fiber of each analysis unit based on the Brillouin frequency shift signal, wherein the optical fiber comprises a plurality of analysis units; for any analysis unit, obtaining a true dislocation displacement vector to be determined according to the initial length of the analysis unit and the deformation length of the analysis unit; Decomposing the true dislocation displacement vector to be determined into a projection component along the axial direction of the optical fiber and a normal projection component perpendicular to the axial direction of the optical fiber, and taking the normal projection component as equivalent shear displacement; Forming an equivalent right triangle model based on the initial length of the analysis unit, the deformation length of the analysis unit, the projection component along the axial direction of the optical fiber and the equivalent shear displacement; based on the equivalent right triangle model, a pull-shear coupling equation is obtained according to the geometric relationship; and determining equivalent axial strain and equivalent shear displacement by adopting a pull-shear coupling equation based on the total axial strain of the optical fiber of the analysis unit.
2. The method for monitoring the tensile shear deformation and decoupling of the coal rock mass based on the generalized equivalent geometric model according to claim 1, wherein the method is characterized in that based on the brillouin frequency shift signal, the total axial strain of the optical fiber corresponding to each analysis unit is obtained, and specifically comprises the following steps: And performing temperature compensation on the Brillouin frequency shift signal to obtain the total axial strain of the optical fiber of each analysis unit.
3. The method for monitoring the decoupling of the tensile shear deformation of the coal rock mass based on the generalized equivalent geometric model according to claim 1, wherein the geometric relationship in the right triangle model is represented by adopting the following formula: ; Wherein, the For the deformed length of the analysis unit, For the initial length of the analysis unit, For an equivalent axial strain to be present, Is equivalent shear displacement.
4. The method for monitoring the pull-shear deformation decoupling of the coal rock mass based on the generalized equivalent geometric model according to claim 1, wherein the pull-shear coupling equation is as follows: Wherein, the method comprises the steps of, For an equivalent shear displacement of the material, For the initial length of the analysis unit, For an equivalent axial strain to be present, Is the total strain in the axial direction of the optical fiber of the analysis unit.
5. The method for monitoring the tensile-shear deformation decoupling of the coal rock mass based on the generalized equivalent geometric model according to claim 1, wherein the method for determining the equivalent axial strain and the equivalent shear displacement by adopting a tensile-shear coupling equation based on the total axial strain of the optical fiber of the analysis unit is characterized by comprising the following specific steps: and introducing a nonlinear geometric coupling factor to correct the Lag-shear coupling equation to obtain a corrected Lag-shear coupling equation, wherein the corrected Lag-shear coupling equation is as follows: Wherein, the method comprises the steps of, As a non-linear geometrical coupling factor, For an equivalent axial strain to be present, For the total axial strain of the optical fibers of the analysis unit, For an equivalent shear displacement of the material, An initial length for the analysis unit; And based on the total axial strain of the optical fiber of the analysis unit, determining equivalent axial strain and equivalent shear displacement by adopting a corrected pull-shear coupling equation.
6. The method for monitoring the pull-shear deformation decoupling of the coal rock mass based on the generalized equivalent geometric model according to claim 5, wherein the method for determining the equivalent axial strain and the equivalent shear displacement by adopting a corrected pull-shear coupling equation based on the total axial strain of the optical fiber of the analysis unit is characterized by comprising the following specific steps: Decomposing the total axial strain of the optical fiber of the analysis unit by utilizing wavelet transformation to obtain a high-frequency component and a low-frequency component; Determining an equivalent axial strain based on the low frequency component; Based on the high frequency component, the equivalent shear displacement is determined by adopting a corrected pull-shear coupling equation.
7. The method for monitoring the decoupling of the tensile shear deformation of the coal rock mass based on the generalized equivalent geometric model according to claim 6, wherein a formula is adopted Determining an equivalent shear displacement, wherein, Is a high frequency component.
8. A coal rock mass tensile shear deformation decoupling monitoring system based on a generalized equivalent geometric model, which is connected with a sensing optical cable implanted in a coal rock mass and containing optical fibers, and the method for monitoring the coal rock mass tensile shear deformation decoupling based on the generalized equivalent geometric model according to any one of claims 1-7 is applied, and is characterized in that the system comprises: The optical fiber axial total strain acquisition module is used for acquiring Brillouin frequency shift signals of each analysis unit after the coal rock mass is pulled, sheared and deformed, and obtaining the optical fiber axial total strain of each analysis unit based on the Brillouin frequency shift signals; The system comprises a tensile-shear coupling equation acquisition module, an equivalent right triangle model, a tensile-shear coupling equation generation module and a tensile-shear coupling equation generation module, wherein the tensile-shear coupling equation acquisition module is used for acquiring a true dislocation displacement vector to be determined according to the initial length of an analysis unit and the deformation length of the analysis unit for any analysis unit; And the axial strain and shear displacement determining module is used for determining equivalent axial strain and equivalent shear displacement by adopting a pull-shear coupling equation based on the total axial strain of the optical fiber of the analysis unit.
9. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor executes the computer program to implement the method for decoupling monitoring of tensile shear deformation of a coal rock mass based on a generalized equivalent geometric model according to any one of claims 1-7.
10. A computer readable storage medium having stored thereon a computer program, which when executed by a processor implements the method for decoupling deformation monitoring of coal rock mass tensile shear based on a generalized equivalent geometric model according to any one of claims 7.

Description

Coal rock mass tensile shear deformation decoupling monitoring method, system, equipment and medium based on generalized equivalent geometric model Technical Field The application relates to the field of coal mine rock mechanics monitoring, in particular to a coal rock body pulling-shearing deformation decoupling monitoring method, system, equipment and medium based on a generalized equivalent geometric model. Background Deformation monitoring of underground works is critical to ensure the safety and stability of the engineering structure. Conventional deformation monitoring methods, such as borehole tensiometers, multi-point displacement meters, and the like, typically rely on analysis of single point data. Although these methods perform well in fixed point measurements, they have limited monitoring range and are difficult to capture hidden inter-layer drift inside the coal pillar. The distributed optical fiber sensing technology can quickly acquire full-distribution strain data along the structure in real time, and has become an important tool for monitoring deformation of underground engineering. But the tool still has many challenges in practical applications. First, existing monitoring theory is generally based on the "linear strain transfer" assumption that the axial strain measured by the fiber is considered directly equal to the linear elastic deformation of the coal rock mass. However, under the influence of mining, coal pillars tend to experience any angle of inter-layer dislocation. When oblique shearing occurs, the optical fiber is not only subjected to transverse bending, but also to stretching by an axial component. Traditional simple geometric models often assume that the shear is perpendicular to the optical fiber, and cannot adapt to complex crack development morphology in engineering. At this time, the geometrical nonlinear elongation generated by the optical fiber can be misread by demodulation equipment as simple axial stretching, so that the shearing slip is misjudged as stretching damage, and the real deformation characteristic of the whole structure is difficult to comprehensively capture. Compared with the traditional linear analysis, the decoupling analysis based on the generalized geometric model not only can capture axial compression, but also can reflect interlayer shearing dislocation, and provides comprehensive data support for engineering safety. Disclosure of Invention The application aims to provide a coal rock mass tensile shear deformation decoupling monitoring method, system, equipment and medium based on a generalized equivalent geometric model, which can realize accurate decoupling of a complex tensile shear deformation field of a coal rock mass. In order to achieve the above object, the present application provides the following solutions: in a first aspect, the application provides a coal rock mass tensile shear deformation decoupling monitoring method based on a generalized equivalent geometric model, which comprises the following steps: After the coal rock mass is pulled, sheared and deformed, acquiring a Brillouin frequency shift signal of each analysis unit, and obtaining the total axial strain of an optical fiber of each analysis unit based on the Brillouin frequency shift signal, wherein the optical fiber comprises a plurality of analysis units; for any analysis unit, obtaining a true dislocation displacement vector to be determined according to the initial length of the analysis unit and the deformation length of the analysis unit; Decomposing the true dislocation displacement vector to be determined into a projection component along the axial direction of the optical fiber and a normal projection component perpendicular to the axial direction of the optical fiber, and taking the normal projection component as equivalent shear displacement; Forming an equivalent right triangle model based on the initial length of the analysis unit, the deformation length of the analysis unit, the projection component along the axial direction of the optical fiber and the equivalent shear displacement; based on the equivalent right triangle model, a pull-shear coupling equation is obtained according to the geometric relationship; and determining equivalent axial strain and equivalent shear displacement by adopting a pull-shear coupling equation based on the total axial strain of the optical fiber of the analysis unit. In a second aspect, the application provides a coal rock mass tensile shear deformation decoupling monitoring system based on a generalized equivalent geometric model, which is connected with a sensing optical cable implanted in the coal rock mass and comprises the following components: The optical fiber axial total strain acquisition module is used for acquiring Brillouin frequency shift signals of each analysis unit after the coal rock mass is pulled, sheared and deformed, and obtaining the optical fiber axial total strain of each analysis unit based on the Brill