热效应作用下P波入射成层弹性地基场地的地震响应  

Seismic response of P-wave incident layered elastic foundation site under thermal effect

作　　者：杨奕琪 马强 YANG Yiqi;MA Qiang(School of Civil Engineering and Water Resources,Qinghai University,Xining 810016,China;Key Laboratory of Energy-Saving Building Materials and Engineering Safety,Qinghai Province,Xining 810016,China)

机构地区：[1]青海大学土木水利学院,青海西宁810016 [2]青海省建筑节能材料与工程安全重点实验室,青海西宁810016

出　　处：《浙江大学学报(工学版)》2025年第4期717-729,共13页Journal of Zhejiang University:Engineering Science

基　　金：国家自然科学基金资助项目(52168053);青海省自然科学基金资助项目(2024-ZJ-922).

摘　　要：基于热弹性介质中弹性波的传播理论,建立平面P波入射下的成层弹性地基场地模型.根据亥姆霍兹矢量分解原理,在基岩-成层弹性地基层系统中采用传递矩阵法,推导得到成层弹性地基层中波幅系数转换矩阵,获得热效应作用下平面P波入射成层弹性地基场地地震响应的解析解答.通过数值计算,分析热传导系数、介质温度、固相比热容等热物性参数对成层弹性地基场地地震地面运动的影响规律.结果表明:当入射角为0~90°时,热效应下的水平位移放大系数相对于等温条件下的减小了40.53%,竖向位移放大系数相对于等温条件下的增加了8.28%,成层弹性地基的水平和竖向位移放大系数峰值分别比均质弹性地基的增加了33.17%和38.12%.随着介质温度的增大,水平位移放大系数逐渐减小,竖向位移放大系数逐渐增大;随着频率的增大,地表水平和竖向位移放大系数逐渐增大.软硬土层在土层中的排列次序、固相比热容和热膨胀系数对地表位移放大系数的影响均不可忽视.A model of a layered elastic foundation site under plane P-wave incidence was established based on the propagation theory of elastic waves in the thermoelastic medium.According to the Helmholtz vector decomposition principle,the transfer matrix method was used in the bedrock-layered elastic foundation system to derive the conversion matrix of wave amplitude coefficients in the layered elastic foundation site,and an analytical solution for the seismic response of plane P-wave incident the layered elastic foundation site under the action of thermal effect was obtained.The influence of thermal physical parameters such as heat conduction coefficient,medium temperature,and solid specific heat capacity on seismic ground motion of layered elastic foundation site was analyzed by numerical calculation.Results show that when the incident angle is 0 to 90°,the horizontal displacement magnification factor under thermal effect decreases by 40.53%compared with the isothermal condition,and the vertical displacement magnification factor increases by 8.28%compared with the isothermal condition.The peaks of horizontal and vertical displacement magnification factors of layered elastic foundations increase by 33.17%and 38.12%,respectively,compared to those for homogeneous elastic foundations.With a rise in the medium temperature,the horizontal displacement magnification factor decreases gradually,and the vertical displacement magnification factor increases gradually.The horizontal and vertical displacement magnification factor increases gradually with an increase in the frequency.The order of soft and hard soil layers in the soil layer,the solid specific heat capacity,and the coefficient of thermal expansion have a non-negligible effect on the amplification factor of the surface displacement.

关 键 词：地震响应 平面P波 热效应 成层弹性地基 传递矩阵法 

分 类 号：TU435[建筑科学—岩土工程]