The main roof strata of 4311 working face in Jinmei group Changping coal mine is dense and hard, and difficult to caving in the process of mining.In order to prevent the overhang area is too large in the process of working face initial mining and initial caving,causes the gas and roof accident,specially using comprehensive pre -splitting method of deep and shallow hole with small borehole (42 mm)anchor cable drilling machine to weaken roof, and deep hole pre -splitting blasting the main roof is given priority,shallow hole blasting fracture anchor cable and increasing deep hole blasting free surface is as the supplement.After roof pre -splitting,the main roof pressure ap-peared when working face top end mining 25.2 m,the effect is remarkable.The technology is simple,reliable,and easy to implement.It has a certain economic and social benefits.%晋煤集团长平矿4311工作面由于老顶岩层致密坚硬，回采过程中不易垮落，为了防止工作面在初采初放时悬顶面积过大，造成瓦斯及顶板事故，特采用小孔径（42 mm）锚索钻机深、浅孔综合预裂方法弱化顶板，以深孔爆破预裂老顶为主，以浅孔爆破破断锚索和增加深孔爆破自由面为辅，顶板预裂处理以后，工作面上端头推进25．2 m 时老顶来压，效果显著。该技术简便可靠、易于实施，具有一定的经济、社会效益，值得推广应用。
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