近场强震作用下上海地区百米高层建筑地震动反应分析

Seismic Response Analysis of One Hundred Meters High-Rise Buildings in Shanghai under Strong Earthquake of Near Field

首先,依据汶川地震中不同震中距基岩地震波记录,选取假设上海近场发生M8.0级强震时的基岩地震波。然后,对上海某百米高层建筑场地进行深覆盖土层地震反应分析,获得该场地在近场强震时的地表波。最后,以此百米高层建筑为例,分析该结构在此地表波作用下的地震动反应特点,从而评估近场强震对上海高层建筑的影响。分析结果表明:结构在双向地震动作用下的反应与单向地震动作用下的反应有明显不同。其中,地震动垂直分量对结构顶层节点竖向反应放大作用显著;地震动水平分量对结构顶层节点三个方向反应都有放大效应;地震动水平分量对结构层间位移角起决定性作用;地震动水平分量对结构底层角柱内力的影响大于地震动垂直分量对其的影响。

To begin with, a bedrock seismic wave as a disastrous M8.0 earthquake wave which was assumed to happen in Shanghai near field was selected, according to the different bedrock seismic wave records during Wenchuan earthquake. Then, the seismic ground responses in site of a hundred meters high-rise building were calculated and the ground seismic waves under the strong earthquake on near field were analyzed. Finally, the characteristics of the seismic response of the building were analyzed and the effect of a strong earthquake in near field was essentially discussed. The numerical results showed that the difference of the seismic response of the structure between hi-direction ground motions and one-way ground motion were obvious. The amplification effect of vertical response to the top floor under the vertical component of ground motion was significant. The horizontal component of ground motion amplified the response of the top floor in three directions. The horizontal component of ground motion affected decisively the displacement angle of the structural story. The horizontal component of ground motion had greater influnce on the inner force in bottom columns than the vertical component.