粒径对岩崩-碎屑流滑震特征的影响  

Landquakes Generated by Debris Falls with Different Particle Sizes

作　　者：罗肖 程谦恭[1,2] 王玉峰[1,2] 李天话 LUO Xiao;CHENG Qian-gong;WANG Yu-feng;LI Tian-hua(Department of Geological Engineering,Southwest Jiaotong University,Chengdu 611756,Sichuan,China;State-province Joint Engineering Laboratory of Spatial Information Technology for High-speed Railway Safety,Southwest Jiaotong University,Chengdu 611756,Sichuan,China)

机构地区：[1]西南交通大学地质工程系,四川成都611756 [2]西南交通大学高速铁路运营安全空间信息技术国家地方联合工程实验室,四川成都611756

出　　处：《地球科学与环境学报》2023年第1期118-130,共13页Journal of Earth Sciences and Environment

基　　金：国家自然科学基金项目(42177131,41877226,41877237)。

摘　　要：岩崩-碎屑流是一种发生在高山峡谷地区,具有高位性、隐蔽性、事件突发性和灾害巨大危害性等特征的地质灾害,滑震信号监测可实现对地质灾害体运动信息的实时捕获,为灾害预警及灾后评估提供重要信息。以颗粒集合体崩落运动过程为研究对象,设计并开展了物理模型实验,分析了颗粒粒径对滑震信号特征的影响,探讨了岩崩-碎屑流撞击过程产生的滑震信号特征及其现实意义。结果表明:①颗粒集合体总质量一定时,滑震信号最大振幅值为17.33 g~39.21g,且随着颗粒粒径的增大而增大;②颗粒集合体总质量一定时,滑震信号包络线平均值、阿里亚斯强度随着颗粒粒径的增大而增大;③粒径为2~4 mm的颗粒集合体产生的滑震信号平均频率为16.95~23.02 kHz,且在总质量一定时,滑震信号的平均频率随着颗粒粒径的增大而减小。本文研究成果以期进一步加深对滑震信号影响因素的认识,并为灾害潜在区域监测预警系统建立、重大地质灾害灾后快速评估、应急响应措施制定等提供理论依据。Debris fall,which is a kind of geological disaster with high position and concealment characteristics,often develops in mountainous areas and occurs suddenly.It poses a great threat to the safety of downstream constructions and persons.Compared with traditional monitoring methods,the seismic signals generated by geophysical flows have certain advantages,which can provide continuous real-time monitoring of geological disasters that occurred hundreds of kilometers away and even far,and provide important information for disaster early warning and post-disaster assessment.Taking the fall processes of granular flows as research objects,a series of physical model experiments of granular flows was designed and conducted here with the kinematic process and seismic signals of granular flows being recorded;the characteristics of the seismic signals under the influence of particle size were detailed analyzed.The results show that①at a constant granular flow volume,the maximum amplitude of the seismic signal is between 17.33 g and 39.21 g,which increases with the increase of particle size;②at a constant granular flow volume,the average value of seismic envelope and Arias intensity increase with the increase of particle size;③the frequency of seismic signal obtained on laboratory scale experiment with particle diameter from 2 to 4 mm is between 16.95 and 23.02 kHz;at a constant granular flow volume,the average frequency decreases with the increase of particle size.The above results can provide a theoretical basis for a deeper understanding of the influencing factors on landquakes,establishment of disaster potential regional monitoring and early warning system,rapid post-disaster assessment of major geological disasters,and development of emergency response measures.

关 键 词：地质灾害 岩崩-碎屑流 颗粒流 物理模型实验 滑震 环境地震学 地震动信号 参数反演 

分 类 号：P694[天文地球—地质学] P642.21