Reasonable Process Parameters Research On Roadway Caving Mining Of Steeply Inclined Seams

Steeply inclined coal seam mining technology is an important part of coal mining technology in China, the complexity of the steeply coal seam occurrence conditions determines the diversity of steeply coal seam mining methods, among them, the roadway caving mining is one of the effective technology in mining steeply inclined thick coal seam in recent years. The key process parameters of roadway caving mining are:section height, section coal pillar height, top-coal loose blasting parameters. The No.5steeply inclined coal seam mining in Luning Da Hangou Coal Limited is the engineering background for the paper, it studies the key techniques and parameters of roadway caving mining in No.5coal seam, and the research contents and conclusions are as follows:(1)This paper conducted field investigation of Han Gou Coal Co. Ltd to collect relevant materials, conducted the rock mechanics experiments on the coal rock of No.5coal seam, and the coal and rock physics mechanics parameters have been measured.(2)By establishing the mechanics model of top-coal to theoretically calculate the transport roadway stress limit equilibrium zone height and top-coal upper goaf edge limit equilibrium zone height and theoretically deduce the reasonable section height; this paper establishes the three-dimensional numerical calculation model of Han Gou Coal Mine No.5coal seam using FLAC3D software, analyzes and studies the top-coal stress, displacement and failure characteristics in different section height to determine the reasonable section height.(3)Based on mechanical model of top-coal breaking backward, this paper uses the theory of elastic foundation beam to analyze the coal body bearing, and get the reasonable section coal pillar height; this paper uses the FLAC3D software to establish the numerical calculation model of the Han Gou Coal Co. Ltd. No.5coal seam, and analyzes coal body stress, failure characteristics to determine the reasonable section coal pillar height.(4)According to the occurrence conditions and coal rock mechanical characteristics of No.5coal seam, combined with the process characteristics of roadway caving mining, this paper studies the top-coal loose blasting parameters, chooses the reasonable loose blasting parameters for Han Gou Coal Co. Ltd. the No.5coal seam and sets loose blasting scheme to ensure the top-coal recovery rate and roadway stability.(5)By the methods of theoretical analysis, numerical simulation and field practice, this paper determines that the No.5coal seam reasonable section height is14m and the reasonable section coal pillar height is lm in the Luning Han Gou Coal Co. Ltd., using the method of deep hole combining with shallow hole to make top-coal loose blasting, and decorate5shot holes,3in top,1in rise side and1in floor; circular step for1.6m.