Gob-side entry retaining method for large-dip-angle coal seam

Abstract

The invention discloses a gob-side entry retaining method for a large-dip-angle coal seam. The gob-side entry retaining method for the large-dip-angle coal seam comprises the steps that firstly, a working face is supported by adopting an anchor rod or an anchor cable and a steel belt; in the working face stoping process, an advance step is constructed from the lower end of a working face in the working face trend, meanwhile, a top plate exposed by the advance step is supported through a plurality of rows of single supporting columns and a hinged top beam, and a row of single supporting columns are matched with a wood bridging piece on the coal wall side of the upper part of the advance step for wall protection; a fixed anchor rod and a fixed anchor cable are arranged on the top plate of the advanced step; a wall protecting net is fixedly connected with the top plate of the advanced step and the bottom of a roadside supporting body, so that the wall protecting net forms a flexible supporting structure; when the working face is pushed forwards for two cycles, one-time column pulling caving is carried out, a row of dense supporting columns are arranged in the column pulling distance range in the trend of the front edge of caving, and the steps are repeated till the work of the whole roadway is completed; after completion, the dense supporting columns in a machine roadway are withdrawn, so that the gob-side entry retaining construction of the large-dip-angle coal seam is realized.

Description

technical field [0001] The invention relates to a gob-side entry retaining method for a coal seam with a large dip angle, and belongs to the technical field of coal mining support. Background technique [0002] Gob-side retaining is a technology for maintaining the original mining roadway by setting support bodies along the edge of the gob in the mining roadway after the mining of the working face. Because of the cancellation of section coal pillars, the reduction of roadway excavation, and the realization of Y-shaped Ventilation methods are increasingly used in coal mining. With the development and utilization of coal resources, coal mining has gradually transitioned from high-quality coal seams to complex coal seams, especially high-inclination coal seams (35°-55°). For coal seam mining with large dip angle, because the natural repose angle of the collapsed gangue in the goaf is smaller than the dip angle of the coal seam, it will naturally roll and accumulate towards the...

AI Technical Summary

Problems solved by technology

At present, the widely used gob-side entry retention technology is mostly suitable for mining in near-horizontal or gently inclined coal seams, and the construction technology is relatively complicated. If it is directly applied to high-inclination coal seams, there will be certain difficulties, and the technology and equipment must be improved

At the same time, the downward impact of the gangue falling in the goaf of the coal seam with a large dip angle will cause great harm to the roadside support technology. The impact of the gangue will lead to the instability of the rigid support body and even cause catastrophe.

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