闪长岩不同卸荷速率声发射特征及非稳定阶段识别  

Acoustic emission characteristics of diorite at varying unloading rates and identification of its unsteady phases

作　　者：刘剑 周宗红[1] 张晶 王春[2] 侯廷凯 乔木 LIU Jian;ZHOU Zong-hong;ZHANG Jing;WANG Chun;HOU Ting-kai;QIAO Mu(Faculty of Land Resources Engineering,Kunming University of Science and Technology,Kunming,Yunnan 650093,China;School of Energy Science and Engineering,Henan Polytechnic University,Jiaozuo,Henan 454003,China)

机构地区：[1]昆明理工大学国土资源工程学院,云南昆明650093 [2]河南理工大学能源科学与工程学院,河南焦作454003

出　　处：《岩土力学》2025年第1期225-232,243,共9页Rock and Soil Mechanics

基　　金：国家自然科学基金资助项目(No.52264019,No.51864023);云南省重大科技项目(No.202202AG050014);云南省基础研究计划项目青年项目(No.202401AU070175)。

摘　　要：岩爆前兆信息准确识别是岩爆监测预警的关键问题。工程实践表明,岩爆灾害为静态孕育到动态破坏的过程,不稳定阶段为岩体失稳和突变导致岩爆发生的关键期,进行该阶段研究对揭示岩爆前兆信息的本质具有重要意义。研究了闪长岩不同卸荷速率声发射特征,并识别了非稳定阶段,分析了幅值、振铃计数、频率等特征,采用随机森林(random forest,简称RF)模型识别非稳定阶段幅值、振铃计数和能量等参数。研究结果表明:应力-幅值-振铃计数-时间出现平静期,相较于平静期后大、中、小值同时出现,初始频率、混响频率、累计初始频率和累计混响频率平静期后激增,且初始频率和混响频率值呈大范围分布,可作为岩爆前兆信息,该阶段均为非稳定阶段,RF模型可以较好地识别声发射非稳定阶段,准确率在81.2%以上。开展岩石力学试验对声发射参数标定,基于RF模型对某金矿非稳定阶段识别,对于岩爆灾害的监测预警有重要意义。Accurately identifying precursor information of rockbursts is a key issue in rockburst monitoring and early warning.Engineering practice has shown that rockburst disasters progress from static incubation to dynamic failure,with the unstable stage being critical for rock mass instability and mutation leading to rockburst occurrence.Studying this stage is crucial for understanding the essence of precursor information of rockbursts.The studies on the acoustic emission characteristics of diorite at different unloading rates and the identification of unstable stages are presented.The characteristics of amplitude,ringing count,frequency,etc.are analyzed,and the random forest(RF)model is used to identify the unstable stages of parameters such as amplitude,ringing count,and energy.The research results indicate that the stress-amplitude-ringing count-time relationship shows a quiet period,during which large,medium,and small values appear simultaneously.The initial frequency,reverberation frequency,cumulative initial frequency,and cumulative reverberation frequency increase sharply after the quiet period.These values are widely distributed and can serve as precursor information for rockbursts.This entire stage is unstable.The RF model can effectively identify the unstable stage of acoustic emission with a minimum accuracy of 81.2%.Conducting rock mechanics experiments to calibrate acoustic emission parameters and identifying unstable stages in a specific gold mine using the RF model is crucial for monitoring and early warning of rockburst disasters.

关 键 词：卸荷速率 非稳定阶段识别 随机森林模型 声发射监测 

分 类 号：TU452[建筑科学—岩土工程]