Nondestructive quantitative testing method for working face three-dimensional mining stress field

Abstract

The invention discloses a nondestructive quantitative testing method for a working face three-dimensional mining stress field; the three-direction mining stress field finally obtained in front of theworking face is obtained by adopting an elastic wave three-dimensional CT technology and a mining stress field data processing system; an initial ground stress test point is arranged in an elastic wave three-dimensional CT test area in front of the working face; the corresponding relation between an elastic wave velocity change gradient and a stress change gradient obtained by adopting a true triaxial loading test and an elastic wave velocity test is fully combined, so that the nondestructive and quantitative testing of the three-dimensional mining stress field in front of the working face isrealized. By adoption of the nondestructive quantitative testing method for the working face three-dimensional mining stress field, the three-direction mining stress field in a coal rock in front of the working face can be quantitatively monitored, and the monitoring result is a continuous mining stress field value; according to the test method, a deep drilling hole to the coal layer of the working face is not needed, so that nondestructive and quantitative monitoring is realized; and the problems that a traditional drilling stress meter testing method can only carry out partial single-direction mining stress qualitative testing, the testing result dispersion degree is high, the reliability is poor, and the like can be solved.

Description

technical field [0001] The invention relates to the technical field of stress field testing, in particular to a method capable of performing non-destructive quantitative testing on a three-way mining stress field in front of a coal mining face. Background technique [0002] Coal seam mining at the working face breaks the balance state of the stress field of the original rock in the coal body, leading to the redistribution of the stress field of the original rock (forming the mining stress field), and forming a depressurization zone, a pressurization zone and a pressure stabilization zone in front of the working face . The mining stress of the working face is the fundamental source of force leading to the fracture of the roof strata of the working face, and the abnormal area of ​​the mining stress field is prone to catastrophic accidents such as large-area fracture pressure of the roof, rock burst, coal and gas outburst, and water inrush. . [0003] At present, drilling str...

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Problems solved by technology

[0008] The invention provides a non-destructive quantitative test method for the three-way mining stress field in the coal rock body in front of the working face, so as to solve the problem that the traditional drilling stress gauge test method can only perform qualitative tests and test results of local single-direction stress Problems such as high dispersion and poor reliability

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