Mine working face top board and bottom board mining breaking fracture development dynamic monitoring method

Abstract

The invention belongs to the technical field of mine working face top board and bottom board mining fracture detection and relates to a mine working face top board and bottom board mining breaking fracture development dynamic monitoring method. The method includes the steps that firstly, mine working face mining surrounding rock numerical values are simulated, and according to a numerical simulation calculation result and the working face top board and bottom board plastic range distribution condition, a working face tunnel is constructed and drilled, and three sets of fracture development dynamic detection holes are formed; secondly, surrounding rock fracture dynamic monitoring detection holes for construction are used, electrodes, tunnel electrodes and measuring lines in the detection holes are distributed, and data of a working face are acquired through a data acquisition transmission line; thirdly, a physical geography model is established and forward and inversion of the data are conducted; finally, mine working face top board and bottom board mining breaking fractures are analyzed. According to the method, the monitoring process is simple, operation is convenient, construction is safe, design is rigorous, the structure is reasonable, underground construction is convenient, and data acquisition efficiency is high.

Description

Technical field: [0001] The invention belongs to the technical field of detection of cracks in the roof and floor of a mine working face, and relates to a method for dynamically monitoring the development of cracks in the roof and floor of a mine working face based on resistivity detection. Background technique: [0002] With the exploitation of coal resources, the depth of coal mining in China has shifted from shallow to deep; coal production areas have gradually shifted from the middle and east to the west and northwest. For the mining of deep coal resources, the geological structure and hydrogeology have become increasingly complex, and the pressure and mining The depth of damage caused by dynamic stress to the floor continues to increase, and the problem of water inrush from the floor is becoming more and more serious. For coal seams in Ningxia, Western Ordos, Shaanxi and Xinjiang, the roof rocks of coal seams are mostly mudstone with soft rock mechanical properties, and hard ...

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Problems solved by technology

[0003] At present, the main methods for detecting the development of coal seam mining fractures include drilling double-end plugging leak detection method, ultrasonic detection method, borehole imaging method and geophysical prospecting method. Among them, the ultrasonic detection method is only applicable to the situation where there is water in the coal seam floor borehole. The water in it is used as the ultrasonic coupling medium, but this method cannot be used for observation holes in the bottom plate holes or roof water-conducting cracks where there is no water; the detection principle of the borehole imaging method is the imaging of the borehole camera, which can only be observed The development of fissures in the surrounding rock wall can be used to infer the development degree of fissures in the entire rock formation; in the case of turbid water and high-temperature steam in the borehole, the borehole imaging cannot be observed; the borehole resistivity method is often used in geophysical prospecting methods. By measuring the electrical characteristics of the surrounding rock of the borehole, and using the corresponding relationship between fractures and resistivity, the fracture development characteristics of the entire rock formation can be inverted. The shape and dynamic evolution of mining fractures cannot be realized; the double-end plugging leak detection method is currently the most practical and comprehensive method for detecting water-conducting fractures. relationship, to detect the degree of development of mining fissures, but this method requires corresponding water and air pipelines for on-site construction, and cannot dynamically present the development of mining fissures, especially for boreholes with high roof fissures, due to static water Due to the existence of pressure, the water injection pipeline depends on the drill pipe, and the sealing of the water injection pipeline hinders the detection of water-conducting fracture zones in thick coal seams; for observation holes with deep mining fractures in the floor, also due to the existence of hydrostatic pressure, lead to The water injection pressure is high, and the sealing of the airbag becomes the main problem affecting the observation accuracy

To sum up, the existing detection methods of coal seam mining fracture development have their corresponding limitations.

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