摘要
巷帮锚杆锚索预紧力不匹配是造成高煤帮巷道支护失效的重要原因之一。本文分析了某矿30211综采工作面回风巷帮锚索崩断伤人事故原因,采用FLAC 3D软件模拟了巷道采用锚杆、锚索联合支护时二者的匹配关系。结果表明:锚杆、锚索两种延伸率差别很大的材料用在同一条巷道的同一侧帮时,延伸率小的锚索承担的载荷较大,先破断;锚杆、锚索预紧力联合作用在巷道帮部围岩表面及内部附近形成了大小不等的压应力区,随着预紧力的增大,压应力值和范围也在不断扩大;锚杆的预紧力矩设定在200~300 N·m之间,且锚索的预紧力设定在200~250 kN之间,是比较合理的匹配方案。研究结果对高煤帮巷道支护设计和施工具有一定的指导意义。
The mismatch of pre-tightening force of bolt and cable in roadway side is one of the important reasons for the failure of roadway support in high coal side.This paper analyses the cause of the breaking and wounding accident of the anchor rope in the back air roadway of 30211 fully mechanized mining face in a mine,and simulates the matching relationship between the two when the roadway adopts the combined support of anchor rod and anchor rope by FLAC 3D software.The results show that when the two materials with different elongation are used in the same side of the same roadway,the load of the anchor cable with small elongation is larger and breaks first;the combined action of the anchor bolt and the pre-tightening force of the anchor cable forms different compressive stress zones on the surface and near the interior of the surrounding rock of the roadway.With the increase of the pre-tightening force,the value and range of the compressive stress are also expanding.The pre-tightening moment of anchor is set in 200-300 N·m,and the pre-tightening force of anchor cable is set in 200-250 kN,which is a reasonable matching scheme.The research results have a certain guiding significance for the design and construction of high coal roadway support.
作者
方树林
FANG Shulin(Coal Mining&Designing Department,Tiandi Science&Technology Co.,Ltd.,Beijing 100013,China)
出处
《中国矿业》
北大核心
2019年第12期137-141,共5页
China Mining Magazine
基金
国家重点研发计划“千米深井围岩控制及智能开采技术工程示范”项目资助(编号:2017YFC0603006)
中煤科工集团创新基金“基于水力压裂干预的工作面末采期顶板断裂规律及应力传递机理研究”项目资助(编号:2018-TD-QN025)
关键词
高煤帮巷道
锚杆锚索联合支护
支护失效
预紧力匹配
coal roadway with high roadside
bolt and cable support
support failure
pre-tightening force matching