摘要
为有效提取岩石失稳破坏的前兆信息,针对岩石试样在外载荷作用下失稳破坏前伴随有微震、电荷感应、自电位和声发射等信号的变化特性,建立岩石变形破裂过程多参量综合监测系统,对试样在不同加载速率下变形破裂过程微震、电荷感应、自电位和声发射进行同步监测。实验结果表明:试样在失稳破坏前都有明显的微震、电荷感应、自电位和声发射前兆信号,岩石性质不同,岩石变形破裂过程中微震、电荷感应、自电位和声发射信号明显不同,花岗斑岩的前兆信号比大理岩的前兆信号明显丰富。声发射监测数据能较好地反映岩石的微小破裂情况,可利用声发射进行微裂纹的定位,可以较好地反映电荷感应和自电位前兆信息,试样变形破裂过程的电荷感应和自电位信号比微震信号更早发生,受到的干扰更小,可利用早期的电荷感应和自电位信号进行提前预警,当频繁出现同步且幅值较大的各参量信号时,表明岩石即将进入失稳破坏阶段,可利用微震和声发射对微裂纹进行定位,微震、电荷感应、自电位和声发射信号相互对比分析从而准确获得岩石失稳破坏的前兆信息。
In order to obtain the effective precursory information of instability destruction of rock, a multi- parameter comprehensive monitoring system for rock deformation and failure process was set up to investigate the abnormal signals of rock samples due to external loads, includeing microseismic, charge induction, self-potential and acoustic emission, etc. The monitoring system is used to synchronously monitor the deformation and fracture process under different loading rates. The results show that there are obvious precursory signals including of microseismic, charge induction, self-potential and acoustic emission before the sample instability. The signals of microseismic, charge induction, self-potential and acoustic emission are obviously different for different rocks, and the signals of granite porphyry are more abundant than the signals of marble. The acoustic emission monitoring data can better reflect microcracks of rock. The acoustic emission can be used for microcrackslocation, and reflect the precursor information of charge induction, self-potential better. The signals of charge induction and self-potential during the deformation and failure process occur much earlier than microseismic signals, and the interference is smaller. So the early signals of charge induction and self-potential can be used for early waming. It is also shown that the rock is about to enter the instability and failure phase when the various parameter signals of synchronization and larger amplitude appear frequently. The microseismic and acoustic emission can be used for microcracks location. The precursor information of rock samples＇ instability destruction can be obtained accurately based on the comparative analysis of signals ofmieroseismic, charge induction, self-potential and acoustic emission.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2017年第1期107-123,共17页
Chinese Journal of Rock Mechanics and Engineering
基金
国家自然科学基金面上项目(51274114)
国家自然科学基金青年基金项目(51204087)
中国博士后科学基金特别资助项目(2014T70103)~~
关键词
岩石力学
岩样变形破裂
微震
电荷感应
自电位
声发射
前兆
rock mechanics
fracture process of rocks
microseismic
charge induction
self-potential
acousticemission
precursor
