摘要
煤柱尺寸大小影响巷道围岩稳定性,通过不同煤柱尺寸软煤巷道围岩变形与应力分布相似模拟实验,研究了不同煤柱尺寸下巷道围岩裂隙、岩层移动的演化特征与巷道围岩应力、支架载荷的分布规律,确定了巷道围岩初始扰动与临界失稳的煤柱尺寸。结果表明:软煤平巷围岩裂隙演化特征表现为两帮煤体裂隙水平扩展后的顶板裂隙产生,围岩失稳诱发点为巷道两帮上角部;当煤柱尺寸小于300 mm后,巷道两帮表现为非对称塑性破坏后顶板裂隙扩展的加剧,顶板下沉量、两帮移近量与巷道围岩应力、支架载荷变化剧烈,围岩与支架最大应力集中系数分别为2.53和1.67;当煤柱尺寸为150 mm时,煤柱两侧的巷道围岩裂隙与采区煤壁裂隙贯通,煤柱呈屈服承载状态,巷道支架载荷右侧大于左侧,巷道围岩稳定性降低;对巷道围岩稳定性产生影响的煤柱尺寸为300 mm,保证巷道围岩稳定性的最小煤柱尺寸为150 mm。
Coal pillar size can affect the stability of gateway surrounding rock. Based on similar simulation experiment of surrounding rock deformation and stress distribution in weaken-coal gateway with different pillar size, the paper studied the evolution of surrounding rock cracks and strata movement,analyzed stress distribution of surrounding rock and supports with different pillar size,and determined the pillar size of the initial disturbance in gateway surrounding rock and the critical instability. The results showed that,the crack extension of level weaken-coal surrounding rock was roof crack initial following two-side horizontal extension,whose induce points were in two sides near to two roof angles. When coal pillar was less than 300 mm,roof cracks extended seriously following two-side asymmetric plastic damage,roof subsidence,two-side convergence,surrounding rock stress change and support loading were severe,the peak stress-concentration coefficients of surrounding rock and support were 2.53 and 1.67 respectively. When pillar was 150 mm,cracks in two pillar sides were connected with ones in coal wall of mine area, the pillar showed yield bearing,loading on right gateway support was more than on left one,and the surrounding rock stability decreased. The pillar size affecting surrounding rock stability was 300 mm,minimum pillar guaranteeing surrounding rock stability was 150 mm.
作者
辛亚军
李梦远
安定超
卜庆为
郝海春
Xin Yajun;Li Mengyuan;An Dingchao;Pu Qingwei;Hao Haichun(School of Energy Science and Engineering,Henan Polytechnic University,Jiaozuo,Henan,454000,P.R.China;Collaborative Innovation Center of Coal Work Safety,Henan Province,Jiaozuo 454000,P.R.China;School of Mining and Coal,Inner Mongolia University of Science and Technology,Baotou,Inner Mongolia 014010,P.R.Chinac)
出处
《地下空间与工程学报》
CSCD
北大核心
2018年第6期1519-1526,1557,共9页
Chinese Journal of Underground Space and Engineering
基金
国家自然科学基金(51374091)
河南省教育厅科学技术研究重点项目(14B440001)
河南省科技攻关计划项目(172102310639)
关键词
软煤巷道
围岩控制
煤柱尺寸
作用关系
稳定性
weaken-coal gateway
surrounding rock control
pillar size
interaction relation
stability
