摘要
在揭示山体不同部位和不同场地条件对斜坡地震动响应程度的研究中,学者们多采用振动台和建模等方法,较少使用天然地震下记录到的地震波数据进行研究分析。本研究以2022年芦山M_(S) 6.1级地震为对象,分析了布置于石棉县的强震监测仪所记录到的主震数据,采用小波变换方法分析了山体部位、高程、场地条件等因素对斜坡地震动力响应峰值加速度和Arisa强度的影响,明确了地震时频演变规律。研究结果表明:(1)坡折处水平向放大效应更加明显;(2)南桠河左岸坡体卓越频率为6~10 Hz,右岸为5~12 Hz;(3)深厚风化层场地相较于基岩场地具有更显著的放大效应;(4)S波到达地面时会分异成不同频值,其主频值分别为8.50 Hz和4.20 Hz附近。研究结果可为地震区类似斜坡变形破坏模式和稳定性研究提供参考。
In the study of revealing the response level of slope ground motion at different parts of a mountain and different site conditions,scholars mostly used vibration platform and modeling methods,and seldom used seismic wave data recorded under natural earthquakes for research purpose.In this study,the shock data auto-recorded by strong earthquake monitors installed in Shimian county of Lushan,Sichuan,China were analyzed for analytical interpretation of an earthquake with magnitude 6.1,striking Lushan,Sichuan,China in 2022.It analyzed the influence of mountain position,elevation,site conditions and other factors on the peak acceleration and Arisa intensity of slope seismic dynamic response by wavelet transform method,and the evolution law of seismic time frequency was clarified.Results includes four points:(1)The horizontal magnification effect was more obvious at slope break.(2)The predominant frequency of the slope on the left bank of the Nanya River was 6~10 Hz,and the right bank was 5~12 Hz.(3)A more significant amplification effect was found in the deep weathered layer site than in the bedrock site.(4)When the S wave reached to ground,it branched off into different frequency values,and its main frequency values were around 8.50 Hz and 4.20 Hz,respectively.The research results can provide reference for the study of slope failures in earthquake area,particularly for the study of ground motion response incurred by shocks.
作者
冯卓
王运生
吴昊宸
唐涛
刘世成
FENG Zhuo;WANG Yunsheng;WU Haochen;TANG Tao;LIU Shicheng(College of Environment and Civil Engineering,Chengdu University of Technology,Chengdu 610059,China;State Key Laboratory of Geo-Hazard Prevention and Geo-Environment Protection,Chengdu University of Technology,Chengdu 610059,China)
出处
《山地学报》
CSCD
北大核心
2023年第1期93-102,共10页
Mountain Research
基金
国家自然科学基金(41877235)
国家重点研发计划项目(2017YFC1501000)
国家创新研究群体科学基金(41521002)
地质灾害防治与地质环境保护国家重点实验室自主课题基金(SKLGP2015Z001)。
