窄煤柱综放煤巷钢梁桁架非对称支护机理及应用

针对王家岭煤矿窄煤柱综放煤巷围岩控制难题,分析指出相邻大型综放工作面覆岩剧烈活动及其基本顶对巷道区域直接顶的倾斜挤压力是导致顶板产生水平移动和非对称破坏的本质原因。建立考虑基本顶对直接顶倾斜挤压应力的窄煤柱综放煤巷直接顶力学模型,得出巷道顶板最大变形区域(7.5≤x≤9.5 m)。研发了以钢梁-槽钢组合结构和多根锚固至顶板纵深处锚索为关键部件的多锚索钢梁桁架系统,阐明其控制原理。建立多锚索钢梁桁架非对称支护的力学模型,得出非对称弯矩减小量分布特征,探讨其与非对称变形的一致性,并结合现场实践确定控制方案。现场实践表明,20103运输巷采用钢梁桁架非对称支护技术后,围岩变形量均控制在安全范围内,实现了对窄煤柱综放煤巷围岩非对称变形破坏的有效控制。

Multiple-cable-girder-truss asymmetric support mechanism and its application in the roadway of fully mechanized top coal caving facewith narrow coal pillar

In terms of the surrounding rock control problem in the roadway of fully mechanized top coal caving face with narrow coal pillarin Wangjialing Mine,the essential reasons,i.e.,the violent overburden motion at adjacent large-scale fully mechanized top coal caving face and the inclined extrusion forcefrom basic roof to immediate roof above the roadway,were analyzed in this paper.Also,authors established the immediate roof mechanical model of fully mechanized top coal caving roadway with narrow coal pillarbased on inclined extrusion forceand obtained the most large deformation region of the roof (7.5≤x≤9.5 m).In addition,authors put forward the multiple-cable-girder-truss system key component of which is the composite structure of steel beam and channel steel and multiple cables anchored in the depth of the roof and clarified its control mechanism.Though building the multiple-cable-girder-truss asymmetric support mechanical model,the distribution characteristics of asymmetric moment reduction and the consistency with asymmetric deformation were discussed and then the support program of test roadway was determined by field practice.After the adoption of the multiple-cable-girder-truss asymmetric support technology in the No. 20103 roadway,the surrounding rock deformation was in safety range,which demonstrated that it achieve an effective control of asymmetric deformation and failure in the fully mechanized top coal caving roadway with narrow coal pillar.