Mechanism and control technology of strong ground pressure behaviour induced by high-position hard roofs in extra-thick coal seam mining

作     者：Chao Pan Binwei Xia Yujun Zuo Bin Yu Changnan Ou Chao Pan;Binwei Xia;Yujun Zuo;Bin Yu;Changnan Ou

作者机构：Mining CollegeGuizhou UniversityGuiyang 550025China National&Local Joint Engineering Laboratory of Gas Drainage in Complex Coal SeamChongqing UniversityChongqing 400044China State Key Laboratory of Coal Mine Disaster Dynamics and ControlChongqing UniversityChongqing 400044China 

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

年 卷 期：2022年第32卷第3期

页      面：499-511页

核心收录：

学科分类：081901[工学-采矿工程] 0819[工学-矿业工程] 08[工学] 0818[工学-地质资源与地质工程] 

基　　金：This work was jointly supported by the National Natural Science Foundation of China(No.51974042) the Shanxi Province Science and Technology Plan Exposed Bidding Project(No.20191101015) the Open Project Program of Key Laboratory of Mine Disaster Prevention and Control(No.JMDPC202102) the Scientific Research Project of Introducing Talents in Guizhou University(No.202045) the Open Project Program of National Engineering Technology Research Center of Development and Utilization for Phosphorus Resources(NECP202210) the Growth Project of Young Scientific and Technological Talents in Universities of Guizhou Province(KY2022139). 

主　　题：Extra thick coal seam High-position hard roof Strong ground pressure behaviour Supporting structures Criteria of ground pressure behaviour Controlling effects 

摘      要：This work aimed at revealing the mechanism of strong ground pressure behaviour(SGPB)induced by high-position hard roof(HHR).Based on the supporting structures model of HHR,a modified voussoir beam mechanical model for HHR was established by considering the gangue support coefficient,through which the modified expressions of limit breaking span and breaking energy of HHR were deduced.Combined with the relationship between the dynamic-static loading stress of supporting body(hydraulic support and coal wall)and its comprehensive supporting strength,the criteria of ground pressure behaviour(GPB)induced by HHR were discussed.The types of Ⅰ_(1),Ⅰ_(2),Ⅱ_(1),andⅡ_(2) of GPB were interpreted.Results showed that types Ⅰ_(1) and Ⅰ_(2) were the main forms of SGPB in extra-thick coal seam mining.The main manifestation of SGPB was static stress,which was mainly derived from the instability of HHR rather than fracture.Accordingly,an innovative control technology was proposed,which can weaken static load by vertical-well separated fracturing HHR.The research results have been successfully applied to the 8101 working face in Tashan coal mine,Shanxi Province,China.The results of a digital borehole camera observation and stress monitoring proved the rationality of the GPB criteria.The control technology was successful,paving the way for new possibilities to HHR control for safety mining.