长平矿保护层开采时上覆岩层移动规律研究

Research on Overlying Strata Movement Rules on Protection Layer Mining in Changping Coal Mine

开采保护层是突出矿井防治煤与瓦斯突出的主要有效方法之一。长平矿3#煤层属于较难抽采煤层,为了安全开采3#煤层,应首先开采其下部邻近8#煤层,以对3#煤层起到卸压保护作用。本文以8#煤层所属84301工作面为试验对象,利用通用离散元程序(UDEC)数值模拟方法,模拟分析了84301工作面矿压显现规律,确定了工作面直接顶及老顶初次垮落步距和周期垮落步距,研究了84301工作面围岩应力分布规律及围岩位移量规律,可为被保护层3#煤层开采时顶板管理等提供技术参考。

It is one of the main effective methods of mining protective layer to prevent and control coal and gas outburst.No.3 coal seam of Changping coal mine is the more difficult to extracting seam.In order to mine No.3 coal seam safely,firstly exploits adjacent No.8 coal seam to pressure relief protect No.3 coal seam.In this paper,84301 working face as test object,utilizes UDEC numerical simulation method,simulatively analyzes the mine pressure behavior of 84301 working face,ensures the initial and periodic caving step distance of immediate roof and upper roof,studies the surrounding rock stress distribution rules and rock displacement rules of 84301 working face.It can provide technical reference for protected layer No.3 coal seam mining and roof control.