摘要
本文按照三种规范(中国建筑抗震设计规范(GB50011 2001)、美国FEMA NEHRP规范(2000)、欧洲结构抗震规范(EUROCODE8,1998)),利用钻孔和剪切波速资料,对天津滨海地区的场地土类别进行研究。通过场地地震动效应分析,研究该场地土对地震动的影响。结果表明,对于滨海场地,简单的场地类别划分难以反映软土场地的实际情况;滨海软土场地对地震动加速度的幅值和频谱的影响非常明显,其对峰值加速度的放大倍数高达1.9,但受土的非线性变形影响,随地震动输入的增大其放大倍数呈非线性降低;软土场地使得加速度反应谱谱形变宽,特征周期变大,变化幅度在0.1s～0.4s。
In the light of shear wave velocity and borehole data, the seashore site in Tianjin is classified by three codes, i.e. Chinese code for seismic design of buildings (GB50011-2001), Recommended provisions of NEHRP of U.S. and EUROCODE 8, then the effect on ground motion caused by the site is discussed. The results show that (1)it is hard to represent the real characteristics of the seashore site by the brief classification, and (2)the seashore soft soil gives a remarkable effect on the magnitude and spectrum of the ground motion, the acceleration is magnified up to 1.9 times due to the nonlinear deformation of the soil,and the amplification factor is reduced nonlinearly with the increase of ground motion input, (3)the spectrum is broadened and the characteristic period is extended by 0.1sec to 0.4sec.
出处
《地震工程与工程振动》
CSCD
北大核心
2004年第2期46-52,共7页
Earthquake Engineering and Engineering Dynamics
基金
中国地震局"十五"重点科研项目
关键词
地震动
场地类别
放大效应
特征周期
seashore site in Tianjin
site classification
amplification effect
predominant period
