煤矿小孔径预应力锚索破断原因分析及对策  

Cause Analysis and Countermeasures of Small Diameter Pre-stress Anchored Cable Breakage in Coalmine

作　　者：石垚[1,2] 林健[1,2] 王正胜[1,2] 杨景贺[1,2] 

机构地区：[1]天地科技股份有限公司开采设计事业部,北京100013 [2]煤炭科学研究总院开采设计研究分院,北京100013

出　　处：《煤矿开采》2015年第5期93-96,共4页Coal Mining Technology

基　　金：国家自然科学基金(U1261211);中国煤炭科工集团科技创新基金项目(2013MS010);天地科技股份有限公司青年创新基金项目(KJ-2015-TDKC-05)

摘　　要：针对复杂困难条件下煤矿巷道支护锚索普遍存在的破断问题,通过实验室试验和现场巷道顶板煤岩层变形规律验证了锚索破断的原因,并提出了针对性解决措施。研究结果表明,井下锚索破断主要有2种形式:锚索锁具附近破断和锚索中部破断。锚索锁具附近破断的原因主要是锚索工作过程中与巷道岩面垂线夹角过大造成锚索受到拉-弯-剪复合应力作用所致;锚索中部破断主要是由于顶板岩层强烈错动导致锚索在受到较大拉应力情况下受岩层弯曲错动剪切所致。针对锚索的不同破坏形式,建议采取垂直岩面布置锚索、选择延伸率较大和屈服强度比较低的1×19股锚索、减小锚索长度、增加锚杆锚索预紧力的方法来解决锚索破断问题。In order to solve breakage problem of anchored cable generally occurred in roadway with complex and difficult conditions, applying laboratory experiment and field observation of roof deformation, breakage cause of anchored cable was obtained and counter-measures was put forward. Results showed that there were 2 positions of anchored cable breakage：one was near lockset and the other was at middle part of anchored cable. The first position breakage was resulted from tension-bend-shear combined stress which was caused by large angle of anchored cable and vertical line of rock-face. The second position breakage was resulted from large tension stress which was caused by rock strata strong dislocating. For different breakage, following countermeasure was put forward including arranging anchored cables which were vertical to rock-face, applying 1×19 anchored cable with large ductility and low yield strength ratio, reducing anchored cable length and adding anchored bolt and cable pre-force.

关 键 词：锚索 破断 原因分析 对策 

分 类 号：TD350.4[矿业工程—矿井建设]