摘要
应变岩爆是在巷道开挖过程中,由于开挖引起围岩应力重分布从而诱发岩爆的现象,对采矿和隧道施工中的人员及设备安全构成重大威胁。利用自主研发的应变岩爆实验系统,开展完整及含不同钻孔数量砂岩试样的应变岩爆实验,运用高速摄影采集岩爆全过程图像,采用声发射、数字散斑等监测手段采集相关数据,以此研究不同钻孔数量条件下砂岩应变岩爆的破坏特征,探讨了在本实验条件下钻孔数量对应变岩爆的影响。结果表明:随着钻孔数量的增加,岩爆剧烈程度降低;声发射累计计数和累计能量值均减少,声发射活动程度降低,表明岩体内微破裂减少;岩爆弹射碎屑的速度及动能下降,岩爆风险等级由强烈岩爆降低,弹射碎屑破碎程度降低;岩爆时刻岩样竖直向和水平最大位移增加,变形能力提高。通过实验证明钻孔卸压措施对岩爆灾害具有良好的防治效果。
Strainburst is a rockburst phenomenon induced by the redistribution of surrounding rock stress in the process of roadway excavation,which poses a major threat to the safety of personnel and equipment in mining and tunnel construction.In this paper,the self-developed strainburst experiment system is used to carry out strainburst experiments of intact sandstone samples and samples with different numbers of boreholes.High-speed photography is used to collect images of the whole process of rockburst,and monitoring methods such as acoustic emission and digital speckle are used to collect relevant data.Based on the data,the failure characteristics of the sandstone strainburst under the conditions of different drilling numbers are studied,and the influence of the number of drilling holes on the strainburst is discussed under.The results show that with increasing the number of boreholes,the intensity of rockburst decreases,the accumulative count and accumulative energy value of acoustic emission decrease,and the activity degree of acoustic emission decreases,indicating that the micro-fracture in the rock body decreases.When the kinetic energy decreases,the rockburst risk level decreases from a strong rockburst,and the fragmentation degree of the ejected debris decreases.When the rockburst occurs,the vertical and horizontal maximum displacements of the rock sample increase,and the deformation capacity increases.The experiments show that the measures of borehole pressure relief have a good prevention and control effect on rockburst disasters.
作者
刘冬桥
刘赫赫
王炀
孙杰
何满潮
彭栋
兰义丰
LIU Dongqiao;LIU Hehe;WANG Yang;SUN Jie;HE Manchao;PENG Dong;LAN Yifeng(State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China;School of Mechanics and Civil Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China;Institute of Geomechanics,Chinese Academy of Geological Sciences,Beijing 100081,China)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2023年第1期100-114,共15页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金资助项目(52074299,41941018)
中央高校基本科研业务费资助(2021JCCXSB03)。
关键词
岩石力学
应变岩爆
钻孔卸压
声发射
rock mechanics
strainburst
drilling pressure relief
acoustic emission
