三峡库区嘉陵江沿岸不同岩石剪切破坏试验次声特征研究  

Study on shear failure experiment infrasound characteristics of different rocks along Jialingjiang River in Three Gorges Reservoir Area

作　　者：刘阳 张议芳 贾东铭 郭小载 余勇 赵小龙 陈乔[2,3] LIU Yang;ZHANG Yifang;JIA Dongming;GUO Xiaozai;YU Yong;ZHAO Xiaolong;CHEN Qiao(College of Architecture and Urban Planning,Chongqing Jiaotong University,Chongqing 400074,China;Chongqing Institute of Green and Intelligent Technology,Chinese Academy of Sciences,Chongqing 400714,China;Chongqing School,University of Chinese Academy of Sciences,Chongqing 400714,China;Key Ground Engineering Project Office,PetroChina Southwest Oil&Gasfield Company,Chengdu 610000,Sichuan,China;Sinopec Research Institute of Petroleum Engineering,Sinopec Shengli Oilfield,Dongying 257000,Shandong,China)

机构地区：[1]重庆交通大学建筑与城市规划学院,重庆400074 [2]中国科学院重庆绿色智能技术研究院,重庆400714 [3]中国科学院大学重庆学院,重庆400714 [4]中国石油西南油气田分公司重点地面工程建设项目部,四川成都610000 [5]中石化胜利油田石油工程技术研究院,山东东营257000

出　　处：《水利水电技术（中英文）》2022年第11期163-176,共14页Water Resources and Hydropower Engineering

基　　金：中国科学院西部学者A类项目(E2296201);重庆市自然科学基金项目(cstc2021jcyj-msxmX0187);三峡库区消落区(重庆段)生态环境调查及生态恢复技术示范项目(5000002021BF40001);西藏自治区日喀则市科技计划项目(RKZ2020KJ01)。

摘　　要：三峡库区地质灾害以发育广泛且危害性巨大的岩质滑坡为主,而导致岩质滑坡的重要原因是岩石剪切型破坏。为了探讨岩质边坡失稳破坏过程中次声波产生的机理,对三峡库区嘉陵江沿岸砂岩、泥岩、灰岩等常见岩石采样,进行岩石剪切破坏过程次声同步监测试验。通过声力学数据预处理,得到次声卓越频率、次声能量、次声事件数等次声特征,系统分析不同条件下岩石剪切破坏过程中次声波响应特征。结果表明:(1)次声预警时间点比声力学提前59~165 s,比岩石彻底破坏提前78~229 s,将归一化能量累计系数>0.6且归一化次声事件率>0.89时,作为岩石破裂预警点的标志。(2)明确了不同试验条件下岩石剪切破坏过程中的次声波信号响应特征,即,在剪切破坏时,砂岩和灰岩等抗剪强度更高的岩石所产生次声卓越频率和次声能量相较泥岩更大,次声事件数更少;随着岩石尺寸的逐渐增大,次声卓越频率逐渐下降;随着岩石水饱和度越高,次声卓越频率、次声事件数和次声能量均呈降低趋势;随着试验轴压增大,次声卓越频率和次声事件数呈线性增大趋势。(3)次声事件数是不同试验条件下关联度最高的次声关键特征敏感因子。研究成果对进一步利用次声开展岩质滑坡的监测和稳定性评价具有重要的理论参考价值。The geological disasters in Three Gorges Reservoir Area are mainly the widely developed rock landslides with great harmfulness,while the important causes of the rock landslides therein are rock shear failures.Therefore,the common rocks such as sandstone,mudstone and limestone along Jialingjiang River in Three Gorges Reservoir Area are sampled and the relevant infrasound synchronous monitoring tests on rock shear failure process are carried out for exploring the infrasonic wave generating mechanism in the process of rock slope instability and failure.Through the acoustic mechanics data pre-processing,the infrasonic characteristics,i.e.the infrasound predominant frequency,infrasound energy,number of infrasound events,etc.,are obtained,and then the response characteristics of infrasonic waves during rock shear failures under different conditions are systematically analyzed.The results show that(1)the warning time point of infrasound is 59~165 s earlier than that of acoustic mechanics and 78~229 s ahead of complete rock failure.When the normalized energy accumulation coefficient is larger than 0.6 and the normalized infrasound event rate is larger than 0.89,it is regarded as the sign of rock fracture early warning point;(2)the response characteristics of infrasonic signals during the rock shear failure under different experimental conditions are determined,that is,the infrasound predominant frequencies and infrasound energies produced by rocks such as sandstone and lime stone with higher shearing strength are larger than those produced by mudstone with fewer infrasound events during shear failure.With the gradual increase of rock size,the predominant frequency of infrasound is gradually decreased and the infrasound predominant frequency,the number of infrasound events and the infrasound energy are all exhibit decreasing trends along with the higher rock water saturation,while the predominant frequency of infrasound and the number of infrasound events exhibit linear increasing trends with the increase of the experimen

关 键 词：滑坡灾害 监测预警 岩石剪切破坏 次声波特征 损伤理论 

分 类 号：P694[天文地球—地质学]