大采高回采巷道保护煤柱局部变形特征监测分析

Monitoring and Analysis of Local Deformation Characteristics of Protective Coal Pillar in Mining Roadway with Large Mining Height

回采巷道煤柱的局部变形是巷道失稳和破坏前兆,由于地下水对保护煤柱的侵蚀作用,在一定程度上影响巷道的稳定性。本文以斜沟矿18503大采高综采工作面为工程背景,采用数值模拟软件COMSOL对煤柱在无支护、有支护条件下的孔隙水压力进行模拟计算,总结出回淹巷道保护煤柱的水流动规律。实验结果表明:在巷道中布置疏水孔,有利于煤柱水的疏导和排放,能有效缓解水流对保护煤柱的侵蚀,尤其是当钻孔长度能够穿透保护煤柱回淹层主裂隙面时,更加有利于煤柱水的疏放;对煤柱施加支护阻力,可在一定程度上减缓水的渗透作用,减缓地下水巷道围岩的侵蚀破坏,根据回淹巷道煤柱水流动规律,为采取科学的疏排水技术措施提供理论依据,同时也为采动影响下大采高回采工作面保护煤柱的稳定性控制提供了参考。

The local deformation of the coal pillar in the mining roadway is the precursor of the roadway instability and destruction,and the stability of the roadway is affected to a certain extent due to the erosion of groundwater on the protective coal pillar.Based on the engineering background of the 18503 large mining height fully mechanized mining face in Xiegou Mine,this paper uses the numerical simulation software COMSOL to simulate and calculate the pore water pressure of the coal pillar under the conditions of no support and support,and summarizes the water flow law of the coal pillar protection in the back flooded roadway.The experimental results show that the arrangement of drainage holes in the roadway is conducive to the drainage and drainage of coal pillar water,and can effectively alleviate the erosion of water flow on the protective coal pillar,especially when the length of the hole can penetrate the main fracture surface of the protective coal pillar back flooded layer,it is more conducive to the drainage of coal pillar water;Applying support resistance to the coal pillar can slow down the infiltration of water to a certain extent,and slow down the erosion and damage of the surrounding rock of the underground water roadway.According to the water flow law of the coal pillar in the flooded roadway,it provides a theoretical basis for taking scientific drainage technical measures,and also provides a reference for the stability control of the protective coal pillar in the large mining height mining face under the influence of mining.