Large-dip-angle coal mining rock burst orientation prevention method

Abstract

The invention relates to the asymmetric stress distribution law of a large-dip-angle coal bed tight roof and stress field evolutionary characters after directional blasting pressure relief and provides a targeted large-dip-angle coal mining rock burst orientation prevention method. The method comprises the steps that 1. roof energy releasing is carried out, according to the stress distribution law of the tight roof, ahead roof deep hole blasting design is carried out, and the purposes that elastic energy in a zone is released, and roof weighting steps and intensity are reduced are achieved; 2. secondary energy consumption is carried out, according to the stress field evolutionary characters after roof orientation elastic energy releasing, elastic energy stored in coal bodies at middle-lower zones in a working face is consumed, and secondary disasters are avoided; and 3. secondary danger relieving is carried out, for a determined dangerous zone, roof deep hole blasting hole and coal body pressure relieving blasting are carried out in time, and a large amount of elastic energy in coal and rock masses is released. Finally, the scour-prevention effects of step-by-step pressure relieving and prevention first are achieved.

Description

technical field [0001] The invention belongs to the field of coal mine safety, and in particular relates to a method for directional prevention and control of rock burst in coal seam mining with a large dip angle. Background technique [0002] The research shows that the fracture mode of the overlying strata in the mining of high dip angle coal seam is different from that of the near-horizontal coal seam. The initial roof fracture is a "V-Y" fracture mode, and the periodic fracture is a "quadrilateral" fracture mode. As a result, the characteristics of rock burst occurrence in large-dip coal seams are spatially asymmetric, that is, the upper roof fracture is prone to induced rock burst, and the lower roof is stable and prone to energy accumulation rock burst. With the increasing depth and intensity of mining, the prevention and control of rockburst in coal seams with large dip angles has become an important issue to be solved urgently in the production of coal mines in my co...

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to provide a method for directional prevention and control of rockburst in large-inclination coal seam mining, which can effectively solve the problem of asymmetrical fracture of the roof of the working face of high-inclination coal seam along the inclination direction, and can avoid the formation of high stress concentration caused by deep hole blasting on the roof. The risk of secondary disasters, timely targeted prevention and control of impact risk areas

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