Breaking mechanism and control technology of sandstone straight roof in thin bedrock stope

作     者：Hualei Zhang Min Tu Hua Cheng Yongzhi Tang Hualei Zhang;Min Tu;Hua Cheng;Yongzhi Tang

作者机构：Key Laboratory of Safety and High-Efficiency Coal Mining Ministry of EducationAnhui University of Science and TechnologyHuainan 232001China School of Resources and Environmental EngineeringAnhui UniversityHefei 230039China Huainan Mining GroupHuainan 232001China 

出 版 物：《International Journal of Mining Science and Technology》 (矿业科学技术学报（英文版）)

年 卷 期：2020年第30卷第2期

页      面：259-263页

核心收录：

学科分类：081901[工学-采矿工程] 0819[工学-矿业工程] 0709[理学-地质学] 0808[工学-电气工程] 08[工学] 0818[工学-地质资源与地质工程] 0708[理学-地球物理学] 0807[工学-动力工程及工程热物理] 0815[工学-水利工程] 0813[工学-建筑学] 0814[工学-土木工程] 

基　　金：The authors are grateful to the National Natural Science Foundation of China(Nos.51574007 and 51604007). 

主　　题：Thin bedrock Key stratum Compulsive roof caving 

摘      要：The key problem to be solved urgently is how to avoid the occurrence of support break-off and water inrush in the stoping of sandstone straight roof under the action of load transfer in unconsolidated aquifer.For this reason,taking the thin bedrock 1602(3)working face of Huainan(the middle part of Anhui Province)Panyi Coal Mine as the engineering background,this study establishes the stope mining model by using the discrete element UDEC software and the mathematics mechanical model of the support load,and analyzes the reason of support crushing and decides to re-mining the working face by using the compulsive roof caving method.It is concluded that when the working face of sandstone straight roof is broken,thevoussoir beamstructure cannot be formed and acts on the support in the form of cantilever beam,but only when it falls to the high key stratum can thevoussoir beamstructure be formed and at this point,at this time,the bracket bears the weight of the rock layer in the range from the fractured sandstone layer to the lower critical layer.The working resistance of the support increases with the increase of the thickness and the breaking length of straight sandstone roof.When the breaking length of the roof reaches a certain extreme value,the support crushing accidents will occur.Managing roof with compulsive roof caving method can reduce the intensity of rock pressure in the stope,and the working face can be safely stoped,which provides a certain reference for similar conditions.