高应力全煤尾巷围岩变形破坏机理及控制技术

Deformation and Failure Mechanisms and Control Technology of Surrounding Rock in High Stress Coal Tail Road

针对高应力综放工作面瓦斯尾巷围岩稳定性控制难题,综合运用理论分析、数值模拟及现场实测的方法分析围岩变形破坏特征。结果表明:在非采动影响期间,巷道两帮塑性区不断向深部发展是引起顶沉和底鼓的根源;受采动影响时,缺乏超前支护是片帮垮顶的主因。据此提出"支顶-控底-助帮"支护理论及技术,即:在尾巷内布设1排混凝土支柱,给顶板强有力地支撑,并将顶板压力传递至底板以控制底鼓,继而减轻两帮载荷,阻止两帮塑性区向深部扩展;同时,对尾巷起超前支护作用。

Aiming at the control problem of surrounding rock in high stress coal inner interlocked tail road of the isolated fully-mechanized caving face,combining with the field investigation,numerical simulation,theoretical analysis,and field monitoring,the deformation failure characteristics of surrounding rock are analyzed. The results show that plastic zone in roadway＇s sides extended constantly is the root of roof convergence and floor heave during un-mining influence period and lack of the pre-support is the main reason of rib spalling and roof caving. Accordingly,the support theory and technology of ＂ roof support-floor control-ribassist＂ are proposed,that is,a row of the sectional block-type concrete pillars will be installed in the inner interlocked tail road in order to support roof forcefully and floor heave is controlled through roof press transferred to floor by the sectional block-type concrete pillars,at the same time,the load of two ribs is reduced so that plastic zone in two ribs is prevented from expanding to the deeper coal mass,and the concrete pillars play role of the fore support during mining influence.