Failure mechanism and control technology of longwall coalface in large-cutting-height mining method  

作　　者：Wang Jiachen Yang Shengli Kong Dezhong 

机构地区：[1]College of Resources & Safety Engineering, China University of Mining & Technology, Beijing 100083, China [2]State Key Laboratory of Coal Resources & Safe Mining, Beijing 100083, China [3]China Coal Industry Top-Coal Caving Mining Engineering Research Center, Beijing 100083, China

出　　处：《International Journal of Mining Science and Technology》2016年第1期111-118,共8页矿业科学技术学报（英文版）

基　　金：financial support from National Basic Research Program of China (No.2013CB227903);the National Natural Science Foundation of General Program of China (No.51574244);the Joint Funds of the National Natural Science Foundation of China (No.U1361209) are greatly appreciated

摘　　要：The stability control of longwall coalface is the key technology of large-cutting-height mining method.Therefore,a systematic study of the factors that affect coalface stability and its control technology is required in the development of large-cutting-height mining method in China. After the practical field observation and years of study,it was found that the more than 95% of failures in coalface are shear failure. The shear failure analysis model of coalface has been established,that can perform systematic study among factors such as mining height,coal mass strength,roof load,support resistance,and face flipper protecting plate horizontal force. Meanwhile,sensitivity analysis of factors influencing coalface stability showed that improving support capacity,cohesion of coal mass and decreasing roof load of coalface are the key to improve coalface stability. Numerical simulation of the factors affecting coalface stability has been performed using UDEC software and the results are consistent with the theoretical analysis. The coalface reinforcement technology of large-cutting-height mining method using the grouting combined with coir rope is presented. Laboratory tests have been carried out to verify its reinforcement effect and practical application has been implemented in several coal mines with good results.It has now become the main technology to reduce longwall coalface failure of large-cutting-height mining method.The stability control of longwall coalface is the key technology of large-cutting-height mining method. Therefore, a systematic study of the factors that affect coalface stability and its control technology is required in the development of large-cutting-height mining method in China. After the practical field observation and years of study, it was found that the more than 95% of failures in coalface are shear failure. The shear failure analysis model of coalface has been established, that can perform systematic study among factors such as mining height, coal mass strength, roof load, support resistance, and face flipper protecting plate horizontal force. Meanwhile, sensitivity analysis of factors influencing coalface stability showed that improving support capacity, cohesion of coal mass and decreasing roof load of coalface are the key to improve coalface stability. Numerical simulation of the factors affecting coalface stability has been performed using UDEC software and the results are consistent with the theoretical analysis. The coalface reinforcement technology of large-cutting-height mining method using the grouting combined with coir rope is presented. Laboratory tests have been carried out to verify its rein- forcement effect and practical application has been implemented in several coal mines with good results. It has now become the main technology to reduce longwall coalface failure of large-cutting-height mining method.

关 键 词：Large-cutting-height mining methodLongwall coalfaceShear failureCoalface stability control technology 

分 类 号：TD823.4[矿业工程—煤矿开采]