摘要
采用Anderson断层模型,推导得出了煤矿井下断层区域应力累积水平的计算指标μm,该指标只与实测最大和最小主应力有关,μm值越大表明区域应力累积水平越高,当μm值达到断层摩擦极限状态或亚摩擦极限状态的应力累积水平μ0时,将可能引起断层冲击地压的发生。通过对40个矿井、120个测点的地应力数据分析表明,采动作用下诱发断层冲击地压的概率和强度与矿井地应力类型、采深H和μm值存在密切关系:地应力类型为σV>σH>σh方位,即使H和μm达到很大也不会发生;只有地应力类型为σH>σV>σh和σH>σh>σV时才有可能诱发断层冲击地压,且相比σH>σV>σh,地应力类型为σH>σh>σV所需的临界值H0和μ0更小。根据龙家堡煤矿地应力测试结果,判定该矿具备断层冲击地压发生危险。根据微震监测数据的分析,提出了断层冲击地压发生的4典型微震特征,即微震事件的高能特征、丛集现象、前震-主震-余震序列和上盘效应。
Through theoretical derivation, this paper presented a calculation index μm for the evaluation on the regional stress accumulation level of faults in three directional stress condition. Research shows that the index/xm is only related to the measured maximum and minimum in-situ stress, the greater the index shows the higher level of accumulation on the regional stress. The analysis of the in-situ stress data of 40 coal mines and 120 test holes showed that whether the fault rock burst happen depends on stress type, mining depth H and index/Xm. If stress type is σv 〉σH 〉σh, even though H and μm especially are very large, the fault rock burst will never happen. The fault rock burst only happen in σH〉σV 〉σb and σH〉σh 〉σv, and when the stress type is σH〉σh 〉σv, the critical value of H0 and μ0 are smaller. On the basis of in-situ stress results in Longjiapu coal mine, this paper evaluates the fault rockburst danger. The authors proposed four typical microseismic characteristics of fault rockburst. They are the characteristics of high-energy microseismic event, cluster phenomenon, foreshock main-shock aftershock sequence and hanging wall effect.
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2016年第12期3008-3015,共8页
Journal of China Coal Society
基金
国家重点研发计划资助项目(2016YFC0801403)
国家自然科学基金资助项目(51574149)
天地科技重点基金资助项目(KJ-2016-TDKC-01)
关键词
断层活化
冲击地压
原地应力
应力累积
微震特征
fault activation
rock burst
in-situ stress
stress accumulation
microseismic characteristics
作者简介
夏永学（1980-），男，湖南临武人，博士。E-mail：xiayongxue1227@sina．com
