摘要
采用间接边界元法(IBEM),对Rayleigh波入射下两邻近山体的地震响应进行了定量分析。结果表明:与单个山体在Rayleigh波入射下的地震响应相比,两山地形的地震反应规律更为复杂,反应特征受控于入射波频率和山体间距等因素。总体上看:入射Rayleigh波频率较低时,两山间距对双山地形地震反应影响较大。低频波入射,受邻近山体影响,迎波面山体水平位移峰值约为入射波水平位移的6.3倍,放大效应可达单山作用的1.5倍。且山体山脚处竖向位移的频谱振荡更为剧烈,特定频率下山脚的竖向位移反应可达单山放大效应的1.6倍。较高频波入射时,迎波面一侧山体受邻近山体影响较小,且对波表现出明显的屏障效应,背波面山体地震反应强度被削弱。
The indirect boundary element method (IBEM)is used to quantitatively analyze the seismic response between two adjacent mountains when the Rayleigh wave is incident.The results are as follows.The seismic response of two adjacent mountains is more complicated than that of a single mountain,and the response characteristics are mainly controlled by the frequency of incident Rayleigh waves and the spacing between the two mountains.Generally speaking,when the frequencies of incident Rayleigh waves are low,the distance between the two mountains has a great influence on the seismic response of mountain topography.When the low frequency waves are incident,due to the influence of adjacent mountain,the peak value of horizontal displacement of the mountain on the side of the incident waves is about 6.3 times of that of the incident waves,and the amplification factor can be up to 1.5 times of the single mountain at specific frequency.At the same time,the vertical displacement amplitude spectra at the mountain foot is strongly affected by the neighboring mountain,and the vertical displacement at the the mountain foot at some specific frequency can reach 1.6 times of that of the single mountain.When higher frequency waves are incident,the mountain on the side of the incident waves is less affected by the neighboring mountains,and has an obvious barrier effect on the waves,as a result,the seismic response of the mountain on the back side of the incident waves is weakened.
作者
张雪
刘中宪
何颖
ZHANG Xue;LIU Zhongxian;HE Ying(Tianjin Key Laboratory of Civil Structure Protection and Reinforcing,Tianjin Chengjian University,Tianjin 300384,China;Tianjin Institute of Earthquake Engineering,Tianjin 300384,China))
出处
《世界地震工程》
CSCD
北大核心
2018年第4期8-15,共8页
World Earthquake Engineering
基金
国家自然科学基金项目(51678390)
天津市应用基础与前沿研究计划重点项目(15JCZDJC39900)共同资助
关键词
邻近山体
间接边界元法
场地效应
瑞利波
adjacent mountains
idirect boundary element method
site effect
Rayleigh waves
