预制裂纹花岗岩单轴压缩全过程声发射特征试验研究  

Experiment study of acoustic emission during fracture process of pre-crack granite under uniaxial compression

作　　者：赵扬锋[1,2] 张超[1] 刘力强[2] 朱小景[1] 

机构地区：[1]辽宁工程技术大学力学与工程学院,辽宁阜新123000 [2]中国地震局地质研究所地震动力学国家重点实验室,北京100029

出　　处：《煤炭科学技术》2017年第7期44-49,138,共7页Coal Science and Technology

基　　金：国家自然科学基金资助项目(51274114;51604141);中国博士后基金特别资助项目(2014T70103);辽宁省自然科学基金面上资助项目(2015020617)

摘　　要：为有效提取含有宏观构造岩体失稳破坏的前兆信息,对不同倾角预制裂纹的花岗岩进行了单轴压缩全过程声发射变化特征试验。结果表明:预制裂纹对岩样峰值强度的影响是显著的,随着预制裂纹倾角的增大,花岗岩试样的峰值强度降低。随着预制裂纹倾角的增大,花岗岩变形破裂过程中声发射事件数和声发射震级都增加,出现声发射前兆信息时试样的应力大幅降低,完整试样的应力为峰值应力的88.5%,裂纹倾角30°时为84.5%,裂纹倾角45°时为56.2%,裂纹倾角60°时为46.3%,声发射前兆信号出现的时间也更为提前。花岗岩变形破裂过程中声发射事件主要集中在预制裂纹区域。声发射监测数据能较好地反映岩石的微小破裂情况,因此对含有宏观构造的岩体应加强宏观构造处的监测。In order to effectively extract the precursor information of rock mass unstable failure with macroscopic structure,granite with different angles of pre-crack were used for experiment study of acoustic emission（ AE） during fracture process of pre-crack granite under uniaxial compression. The results showed that,the influence of pre-crack on the rock peak strength was significant,as the angle of precrack increased,the peak strength of the granite was reduced. As the angle of pre-crack increased,acoustic emission events and acoustic emission magnitude of the granite deformation and fracture process would increase,the stress in AE precursor information was greatly reduced. The stress of the intact sample reached 88.5% of the peak stress,the stress of the sample for 30° crack angle was 84.5%,and 45°crack angle was 56.2%,60° crack angle wass 46.3%.The AE precursor signal was more advance. The acoustic emission events during the granite deformation and failure were mainly concentrated in the pre-crack area. Acoustic emission monitoring data can better reflect the micro rupture of the rock,and the macro structure monitoring of the rock mass should be strengthened.

关 键 词：花岗岩 预制裂纹 失稳破坏 声发射 

分 类 号：TD315[矿业工程—矿井建设]