基于微震与电磁辐射联合监测的多元岩爆预警方法研究  

Multivariate early warning method for rockbursts based on comprehensive microseismic and electromagnetic radiation monitoring

作　　者：周春华[1,2] 李云安[1] 尹健民[2] 汪洋[2] 周朝[2] 郭喜峰[3] ZHOU Chun-hua;LI Yun-an;YIN Jian-min;WANG Yang;ZHOU Chao;GUO Xi-feng(Faculty of Engineering,China University of Geosciences,Wuhan 430074,China;Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of Water Resources,Yangtze River Scientific Research Institute,Wuhan 430010,China;Chongqing Branch Institute,Yangtze River Scientific Research Institute,Chongqing 400026,China)

机构地区：[1]中国地质大学工程学院,湖北武汉430074 [2]长江科学院水利部岩土力学与工程重点实验室,湖北武汉430010 [3]长江科学院重庆分院,重庆400026

出　　处：《岩土工程学报》2020年第3期457-466,共10页Chinese Journal of Geotechnical Engineering

基　　金：国家重点研发计划项目(2016YFC0401803);国家自然科学基金委与广东省联合基金重点基金项目(U1711266);中央级公益性科研院所基本科研业务费项目(CKSF2019190/YT)。

摘　　要：黑龙江某抽水蓄能电站在施工初期的岩爆现象显著,随着地下厂房的深层开挖亟需开展诱发岩爆的监测预警研究。首次采用微震和电磁辐射联合监测方法对水电站地下洞室诱发岩爆的前兆信息进行了识别和特征分析,提出基于微震累计能量、视应力变化梯度、累计视体积率、电磁辐射强度变化率和脉冲数变化率5个量化预警指标的多元预警方法,并在地下厂房潜在岩爆的重点区域进行了应用。研究结果表明:在岩爆诱发期,微震累计能量呈增加趋势,同时呈现视应力减小及累计视体积骤增等特征;电磁辐射强度和脉冲数波动幅度较大,围岩破坏前兆特征显著;基于联合监测的多元预警法判定的预警时间及圈定的微破裂活动空间分布与工程实际相吻合,应用效果较好,可为类似工程岩爆监测预警提供新思路。The phenomenon of rockbursts is notable during the initial stage of the construction of a pumped storage power station in Heilongjiang Province, and thus it is urgent to study the monitoring and early warning of the induced rockbursts along with the deep excavation of the underground powerhouse. The microseismic(MS) and electromagnetic radiation(EMR) monitoring systems are firstly used to identify and analyze the precursory information of the induced rockbursts in the underground caverns of the hydropower station. Meanwhile, a multivariate early warning method is also proposed based on the five quantitative early warning parameters, cumulative energy of microseismic events, apparent stress gradient, cumulative apparent volume rate, variation rate of electromagnetic radiation intensity and variation rate of pulse number. Then the multivariate early warning method is applied in the key area of the underground powerhouse for the potential rockbursts. The comprehensive monitoring results show that there is an increasing trend of the cumulative energy of microseismic events in the early stage of rockbursts while the apparent stress decreases and the cumulative apparent volume increases sharply. In addition, the intensity of electromagnetic radiation and the number of pulses are characterized by large fluctuations, and the precursory characteristics of the surrounding rockmass damage are significant. The application results show that the early warning time and the delineated location of microfracture activity are both consistent with the engineering practice. The proposed method is proved to be effective and may provide new ideas for the early warning of the rockbursts induced in the similar projects.

关 键 词：地下厂房 岩爆 前兆信息 微震监测 电磁辐射 多元预警 

分 类 号：TU452[建筑科学—岩土工程]