摘要
结合现场实测、理论分析和数值模拟等方法,系统研究了"三硬"煤层巷道冲击地压发生的机理。现场地应力测量结果表明,大同矿区存在明显的水平构造应力,通过力学分析发现侧压系数与煤壁冲击线性相关;用关键层理论对坚硬底板冲击地压进行了分析,认为其影响因素有:底板关键层的厚度及其与底板表面的距离、水平构造应力以及工作面采动等;由数值分析结果可知:巷帮的水平位移与施加的水平载荷呈线性正比关系,当水平载荷足够大时,若巷帮一定深度范围内存在或产生了垂直裂隙,且顶底板岩层与煤层分离,巷帮将发生煤壁整体推出型冲击地压;底板岩层水平拉应力最大值随着巷道宽度的增加逐渐向底板深处发展并出现离层,导致底板关键层突然断裂,发生底板冲击地压。
The occurrence mechanism of rock burst in the ＂three-hard＂ coal seam roadway was studied systematically through the comprehensive method of field measurement,theoretical analysis and numerical simulation.The in-situ stress measurement results have shown that there is obvious horizontal tectonic stress in Datong mining area;the mechanical analysis has shown that the rock burst of the coal wall has linear correlation with the lateral pressure coefficient;according to the theory of Key Layer,the influence factors of the hard floor burst are the thickness of the key layer in the bottom,the distance between the key layer and the floor of the roadway,tectonic stress,and mining activity;the numerical simulation has shown that the horizontal displacement of the roadway walls is linearly proportional to the horizontal load,and that if vertical cracks exist or will appear in a certain depth of the roadway walls and the coal bed is separated from the roof and the floor,the rock burst with coal wall holistically pushed out will occur in the two sides of the roadway given that the horizontal load is large enough;with the increase of the roadway width,the horizontal tensile stress in the bottom develops to a deeper position and the separation appears,which caused the sudden fracture of the bottom key layer and thus the floor rock burst.
作者
王旭宏
杜献杰
冯国瑞
康立勋
WANG Xtthong DU Xianjie FENG Guorui KANG Lixun(Shanxi Institute of Technology, Yangquan, Shanxi 045000, China Research Center of Green Mining Engineering Technology in Shanxi Province, Taiyuan University of Technology, Taiyuan, Shanxi 030024, China College of Mining Engineering, Taiyuan University of Technology, Taiyuan, Shanxi 030024, China)
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2017年第4期663-669,共7页
Journal of Mining & Safety Engineering
基金
国家自然科学基金优秀青年科学基金项目(51422404)
国家自然科学基金项目(51574172)
山西省平台基地和人才专项项目(优秀人才科技创新项目)(201605D211003)
山西省高等学校创新人才支持计划项目
山西省煤基重点科技攻关项目(MQ2014-12)
关键词
冲击地压
“三硬”条件
冲击机理
水平荷载
巷道宽度
rock burst
＂three-hard＂ conditions
bursting mechanism
horizontal load
roadway width
