摘要
Abstract
In order to address the severe floor heave problem in soft rock roadways of the No.2 coal seam in Jining Coal Industry,this paper analyzes the influence of floor lithological composition and deformation characteristics on floor heave through theoretical analysis,numerical simulation,and industrial tests.The mechanism of floor heave in soft rock roadways is revealed,and corresponding support and reinforcement measures are proposed.The results show that the main component of the No.2 coal seam floor is kaolinite-type mudstone,whose strength decreases significantly when exposed to water.The relationships between floor heave amount and roadway width,mudstone thickness,and roof and floor strength were simulated using FLAC3D numerical software.With increasing mudstone thickness,the roadway floor heave exhibits a nonlinear characteristic of first increasing and then decreasing,reaching a peak at a mudstone thickness of 10 m.As the roadway width increases,the floor heave amount grows significantly with a negative exponential law.In addition,the special structure of a hard roof and soft floor also exerts a certain degree of influence on the floor heave phenomenon.The author proposes control measures of"reducing roadway span+pressure-relief floor dinting+floor reinforcement".The floor reinforcement adopts a combined scheme of"anchor bolts(cables)+inverted arch beam+concrete pouring",which has achieved good control effects.关键词
软岩巷道/底鼓机理/巷道支护/数值模拟Key words
soft rock roadway/floor heave mechanism/roadway support/numerical simulation分类
矿业与冶金
