预制裂纹花岗岩单轴压缩全过程声发射特征试验研究

发布时间：2018-06-24 20:39

本文选题：花岗岩 + 预制裂纹　；参考：《煤炭科学技术》2017年07期

【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。
[Abstract]:In order to effectively extract the precursor information of the instability and failure of macrostructural rock mass, the acoustic emission characteristics of granite with different inclination prefabricated cracks during uniaxial compression were tested. The results show that the influence of prefabricated cracks on the peak strength of rock samples is significant, and the peak strength of granite samples decreases with the increase of prefabricated crack inclination. With the increase of prefabricated crack inclination, the number of acoustic emission events and the magnitude of acoustic emission increase in the process of deformation and rupture of granite, and the stress of the sample decreases significantly when the precursor information of acoustic emission appears. The stress of the intact specimen is 88.5 of the peak stress. The crack inclination angle is 84.5 at 30 掳, the crack dip angle is 56.2 at 45 掳, the crack dip angle is 46.3 at 60 掳, and the acoustic emission precursor signal appears earlier. During the process of granite deformation and fracture, acoustic emission events are mainly concentrated in prefabricated crack areas. Acoustic emission monitoring data can well reflect the micro-fracture of rock, so the monitoring of macroscopic structure should be strengthened for rock mass with macroscopic structure.
【作者单位】：辽宁工程技术大学力学与工程学院;中国地震局地质研究所地震动力学国家重点实验室;
【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)
【分类号】：TD315

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