不同侧压条件下花岗岩巷道岩爆声发射特征实验研究  

Experimental study on acoustic emission characteristics of granite tunnel rock burst under different lateral pressure

作　　者：于光远[1,2] 张艳博[1,2] 梁鹏[1,2] 田宝柱[1,2] 刘祥鑫[1,2] 

机构地区：[1]华北理工大学矿业工程学院,河北唐山063009 [2]河北省矿业开发与安全技术重点实验室,河北唐山063009

出　　处：《中国矿业》2016年第5期82-86,共5页China Mining Magazine

基　　金：国家自然科学基金项目资助(编号:51374088;51174071);河北省自然科学基金资助(编号:E2012209047);河北省高等学校科学技术研究项目资助(编号:QN2014067)

摘　　要：利用双轴伺服控制试验系统开展开挖卸荷扰动作用下花岗岩巷道岩爆模拟实验,采用声发射系统同步采集岩爆孕育及发生过程的声发射数据,研究不同侧压影响下花岗岩巷道岩爆声发射特征。研究结果表明:双轴条件下,轴压与侧压差值越大,开挖引起的卸荷作用越明显,孔洞内出现初次颗粒弹射的时间越提前;随着侧压的升高,岩爆释放的总能量逐渐增加,声发射累积能量进入"陡增"阶段的时间则相对滞后;声发射振铃计数率能够很好地反映岩爆发生阶段孔洞内应力调整过程,随着侧压的增加,振铃计数率在加载后期的波动模式逐渐由"较低水平波动并出现一定数量跳增点"向"较高水平波动并出现一定数量突降点"转化;结合声发射RA值和AF值可知,巷道岩爆过程即产生张拉破裂又产生剪切破裂,随着侧压的增大,岩爆破坏中剪切成分所占比例逐渐增多。研究结果为岩爆的预测和防治提供了实验基础。An experiment is carried out to simulate granites tunnel rock burst under unloading with biaxial rigid servo-controlled system. The acoustic emission（AE） system produced by American physical acoustics corporation is used to collect data of the AE in the process of rock burst synchronously. The influence of different lateral pressure on tunnel rock burst AE is studied. The result shows that in the conditions of biaxial,axial pressure and lateral pressure difference is large,due to excavation unloading load effect more obvious,the inwall of the hole first ejects rock debris is earlier;The rock burst release of total energy gradually were increased, the cumulative energy of AE into the ＂steep＂ stage of time lag~ The AE ringing count rate can well reflect the stress adjustment of the hole process of rock burst, the AE ringing count rate fluctuation patterns gradually from ＂lower level fluctuation and the emergence of a number of jump points＂ to ＂high level fluctuation and the emergence of a certain number of drop point＂ transformation at the later stage of the loading with the increasing lateral pressure;Tunnel rock burst process that produces a tensile rupture and shear rupture combined with the RA and AF values of acoustic emission, with the increase of lateral pressure, shear failure of rock burst in proportion gradually increased. The results provided the experimental basis for the prediction and control of rock burst.

关 键 词：侧压 卸荷 岩爆 声发射 

分 类 号：TD353[矿业工程—矿井建设]