摘要
在曹村矿10#与11#极近距离煤层开采地质条件基础上,对上位10#煤开采后底板破坏深度及遗留煤柱下方应力分布情况进行了力学计算分析.计算结果表明,10#煤开采后引起的超前支承压力,对其底板最大破坏深度为26.1m,是两层煤间距的2.8倍;煤柱底板的应力分布具有显著的非均匀性.为了衡量煤柱下方底板内应力场的非均布情况,定义了应力场变化率系数ξ.考虑1.5倍的安全系数,并结合采用均布载荷计算得出的错距和底板破坏情况,确定11#煤209工作面回采巷道合理内错距为7.5m.现场应用表明,确定的内错7.5m布置较为合适,巷道支护效果较好,未出现强烈的矿压显现.
Calculations were done to estimate the strain and stress distributions in the floor un- der a coal pillar left in an upper coal seam in close conjunction with an underlying seam. The Caocun coal mine number 10 and 11 seams were used as a basis for the model. The calculations predict that the maximum strain in the floor caused by the bearing pressure from the number 10 seam being mined is 26.1 m. This is 2.8 times the distance between seams. The stress distri- butions in the floor around the pillar are significantly non-uniform. The variation rate coeffi- cient in the stress fields was defined to evaluate this non-uniformity. A inner stagger distance for the gateway of the 209 work face in the number 11 seam was determined, a value of 7.5 m is reasonable for a 1.5 safety factor and an assumed uniform loading. Field studies show this stagger layout to be suitable and that the support from the gateway is improved and that strong pressures do not appear after mining.
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2012年第2期182-188,共7页
Journal of China University of Mining & Technology
基金
煤炭资源与安全开采国家重点实验室自主研究课题(SKLCRSM08X02)
中央高校基本科研业务费专项资金项目(2010ZDP02B02)
国家自然科学基金青年科学基金项目(51004101
50904063)
江苏省"333高层次人才培养工程"项目(苏人才2007-6号文)
关键词
极近距离煤层
孤岛工作面
合理位置
内错距
应力场变化率系数
extremely close coal seam
island workface
optimum position
inner stagger dis-tance
variation rate coefficient in stress fields
