岩石受载破坏前兆特征——声发射平静研究

通过岩石加载室内试验方法，测试了不同岩石破裂全过程的力学特征及其声发射特性，得到了岩石破坏全过程力学特性--岩石的全应力应变曲线、声发射事件累积数、声发射事件率等相关曲线及参数，研究了声发射事件数、事件率与应力水平、时间之间的关系。研究着重讨论了一次性加载过程中非脆性破坏的岩石在加载接近峰值强度时单位时间内的应力增长速度减小，也即这一阶段出现明显的耗时现象；并且在此阶段监测到的声发射事件率出现明显下降，出现声发射相对平静阶段。而对于脆性破坏岩石来说，这一阶段则基本不存在明显的“耗时”现象，声发射的监测也没有声发射相对平静期现象。结合室内试验，还对现场岩体失稳破坏声发射监测中的一些问题进行了总结和分析，为更好地应用声发射手段进行岩体稳定性现场监测预报提供了理论依据、方法和手段。

Study on Acoustic Emission Quietude-Omen Characteristic of Failure of Compressed Rock

Through indoor rock loading method, mechanical characteristics of acoustic emission properties of different rocks in their whole failure process are tested; the mechanical characteristics of the whole rock failure process are obtained, including the relevant curves and parameters such as whole stress-strain curves, number of acoustic emission events and acoustic emission event rate; and the relationships of the number and rate of acoustic emission event with the stress level and time are studied.The stress is laid on the decrease of stress increment in unit time when the stress strength is near to its peak value in one-time loading on non-brittle rock an evident time-consuming phenomenon occurs in this stage.In addition, the rate of the acoustic emission event monitored in this stage decreases obviously and acoustic emission quietude occurs.However, for brittle rocks, there is basically neither evident “time-consuming” phenomenon nor relative acoustic emission quietude in this stage.Combining with the indoor test, some issues in the monitoring of the acoustic emission in in-situ rockmass failure are summarized and analyzed, hereby providing a theoretical basis, method and means for the field monitoring and forecast of rockmass stability by means of acoustic emission.