摘要
为了研究北山花岗岩巷道掘进过程中围岩稳定性,以高放废物地质处置库北山坑探设施为平台,使用IMS微震监测系统进行约180 d连续监测,使用小波分解研究了微震事件的P、S波到时以及频带能量分布特征,通过特征参量研究微震事件的分布特征,使用能量指数研究了完整段和破碎带危险事件分布情况,基于b值研究了围岩的稳定性。结果表明:小波分解可以准确确定微震事件P、S波的到时,并进一步对微震事件进行三维定位;微震事件主要以低震级的小事件为主,高震级大事件很少,完整岩石微震事件可以分为高震级和低震级2部分,破碎岩石微震事件比较集中在低震级区域;完整段危险事件约占总事件的55.88%,破碎带危险事件约占总事件的54.54%;根据微震事件频带能量分布将微震事件分为低频主震型和双频震动型,低频主震型能量主要分布在0~350 Hz,双频震动型能量主要分布在230~700 Hz区域和1 030~1 430 Hz区域,完整岩石中事件为低频主震型,破碎岩石中低频主震型和双频震动型共存。
In order to study the stability of surrounding rock in excavation process of Beishan granite tunnel,the IMS microseismic monitoring system was used for about 180 days continuous monitoring with Beishan exploration tunnel for high level radioactive waste disposal as a platform. Arrival time of P and S waves at microseismic event and characteristics of frequency band energy were researched by wavelet decomposition method,distribution of microseismic events were studied by using characteristic parameters of magnitude and volume potential,the dangerous events of intact rock and broken rock were studied based on energy index,b value was used to determine stability of surrounding rock. The results shows： Arrival time of P and S waves at microseismic events can be accurately determined based on wavelet decomposition,and three-dimensional positioning on the microseismic events can be realized; Microseismic events are mainly dominated by low magnitude events,while high magnitude events are few. The intact rock mass microseismic events can be divided into two parts of high magnitude and low magnitude,but the microseismic events of broken rock are relatively concentrated on low magnitude areas; The dangerous events of the intact rock is about 55.88% of the total events,and that of broken rock is about 54.54%; Microseismic events are divided into main low frequency seismic and dual frequency seismic according to distribution of frequency band energy,where the energy of low frequency seismic is mainly distributed in 0~350 Hz,and the energy of dual frequency seismic is mainly distributed in range of 230~700 Hz and 1 030~1 430 Hz. Microseismic events of intact rock are mainly low frequency seismic,and microseismic events of broken rock co-exist low frequency seismic with dual frequency.
作者
王超圣
周宏伟
王子辉
何树生
刘建锋
Wang Chaosheng;Zhou Hongwei;Wang Zihui;He Shusheng;Liu Jianfeng(School of Mechanics and Civil Engineering, China University of Mining and Technology, Beijing 100083, China;School of Water Resources and Hydropower , Sichuan University, Chengdu 610065, China)
出处
《金属矿山》
CAS
北大核心
2018年第6期153-161,共9页
Metal Mine
基金
"十三五"国家重点项目(编号:2016YFC0600704)
国家自然科学基金项目(编号:51674266)
关键词
北山坑探设施
微震监测
特征参量
能量指数
B值
频带能量
Beishan exploration tunnel
Microseismic monitoring
Characteristic parameters
Energy index
b value
Frequency band energy
