近断层地震动对高层建筑结构抗震性能的影响

Seismic Performance Assessment of High—rise Buildings Subjected to Near—Fault Ground Motion with Fling Effects

摘要:

近断层地震地面运动区别于远场地震，具有滑冲效应特性和向前方向性效应特性.其中，具有单方向速度脉冲和阶跃式永久位移的滑冲效应对长周期结构影响较大.取1999年Turkey地震中台站SKR带有滑冲效应的近断层地震记录作为输入获得弹性和弹塑性反应谱，并详细分析具有不同大小线性特征周期的单自由度体系从线性发展到非线性的整个过程中滑冲效应的作用.以某典型的钢筋混凝土剪力墙高层建筑结构为例，具体研究近断层地震滑冲效应对结构抗震性能的影响.结果表明，近断层地震滑冲效应除了对较长周期的高层结构抗震性能具有不利影响之外，对可能产生较大非线性变形的短周期结构的影响同样不可忽视.

Abstract:

Near fault ground motion with characteristics of fling step and forward directivity is significantly different from far fault ground motion, during which fling step with permanent static displacement offset resulting in one sided velocity pulses could be very effective in causing damage to longer period structures. The record with fling step was selected from the 1999 Turkey earthquake at station SKR. Based on the elastic and elastoplastic response spectrum, a single degree of freedom system with different linear fundamental periods and yield strengths was used to investigate the fling effects. At the same time, a typical reiforced concrete shear wall high rise building was adopted to assess the seismic performance subjected to near fault groud motion with fling effects. Results show that near fault ground motion with fling step significantly affects the performance of high risen structure with longer period, at the same time, for the shorter period structure, fling effects can not be ignored once structure goes to remarkable nonlinear state.