上土下岩地层中平面SH波的传播特性分析  

Analysis of Propagation Characteristics of SH Waves in Upper Soil and Lower Rock Strata

作　　者：周俊 石文革 董玉飞 路世伟 杜国锋[2] 刘洪宇 ZHOU Jun;SHI Wenge;DONG Yufei;LU Shiwei;DU Guofeng;LIU Hongyu(China Gezhouba Group No.3 Engineering Co.,Ltd.,Xi’an 710077,Shaanxi,China;School of Urban Construction,Yangtze University,Jingzhou 434023,Hubei,China)

机构地区：[1]中国葛洲坝集团第三工程有限公司,陕西西安710077 [2]长江大学城市建设学院,湖北荆州434023

出　　处：《高压物理学报》2022年第6期44-51,共8页Chinese Journal of High Pressure Physics

基　　金：国家自然科学基金(41972286);湖北省自然科学基金(2019CFB224);湖北省教育厅科学研究计划项目(Q201913308);荆州市科技计划项目(2019Z18001)。

摘　　要：为研究爆破地震波在层状地层的传播规律,选取平面SH(水平剪切)波作为研究对象,基于弹性波动理论,建立了一般层状地层的刚度矩阵和动力平衡方程,分析了土层与基岩的阻抗比、土层厚度、入射波频率和入射波角度对地表速度与土岩地层界面速度的比值(|u1/u2|)的影响。结果表明:|u1/u2|的各个峰值随着入射波频率的增大而减小,且第2个峰值明显小于第1个峰值,实际工程中应重点关注土层的一阶卓越频率;随着土层阻抗的增大,高频部分的响应越来越强烈,且受入射角的影响也越来越大;当土层较薄时,|u1/u2|高频部分的响应比较明显,但随着土层厚度增加,高频部分的响应越来越小,说明土层的高频滤波作用随着厚度的增加而增强。In order to study the propagation law of blasting seismic waves in general strata induced by underground engineering constructions,shear horizontal(SH)waves were selected as the research object and the stiffness matrix and dynamic balance equation of general layered strata were established based on elastic wave theory.The propagation law of plane SH waves in the soil-rock stratum was studied,and the influence of soil-rock impedance ratio,thickness of soil layers,frequency and incident angle of incident waves on the ratio of ground velocity to soil-rock interface velocity|u1/u2|was analyzed.Results show that the peak|u1/u2|decreases with the increase of the frequency of incident waves,and the secondary peak is obviously smaller than the first peak.In practical engineering,the focus is on the first predominant frequency of the soil layer;as the impedance of the soil layer increases,the high-frequency response becomes stronger and stronger,and it is also increasingly affected by the incident angle.When the soil layer is thin,the high-frequency response of|u1/u2|is more obvious,but it becomes smaller and smaller as the thickness increases.This indicates that the high frequency filtering effect of the soil layer increases with the increase of the thickness.

关 键 词：上土下岩 动力刚度矩阵 弹性波动理论 平面SH波 

分 类 号：O382[理学—流体力学] O521.9[理学—力学]