沈阳金融中心超高层写字楼项目不同阻尼比长周期地震动参数的确定

THE MULTI-DAMPING-RATIO PARAMETERS OF LONG-PERIOD GROUND MOTION USED IN THE SUPER HIGH-RISE OFFICE BUILDING OF THE FINANCIAL CENTER PROJECT IN SHENYANG

介绍了沈阳金融中心超高层写字楼项目如何确定不同阻尼比的长周期设计地震动反应谱,从而避免在周期10s前出现反超现象。反应谱参数确定的原则是新设计反应谱外包或略高于原规范形式的设计反应谱。以"GB50011—2010《建筑抗震设计规范》"为基础,从两方面入手调整不同阻尼比的反应谱参数。一是修改反应谱下降段的形状,去掉直角坐标系下的直线下降段,将曲线下降段延长到原直线下降部分;二是修改下降段衰减指数。这样确定的反应谱在长周期部分不会过于保守,且调整参数的难度和工作量都大大降低。对于高于阻尼比5%和低于阻尼比5%的反应谱,在参数确定上也有不同考虑。

In this paper, we introduce how to obtain the multi-damping-ratio design spectrum parameters of long-period ground motion used in the super high-rise office building of the financial center project in Shenyang, to avoid that the spectral value for large damping-ratio is higher than that of small damping- ratio before 10s period. The principle of determine the response spectrum parameters is that the new design spectrum envelops the original spectrum in the code form outside or is slightly higher than it. Based on ＂GB50011-2010 （（ Code for seismic design of building）） , we adjust the design spectrum parameters in two aspects. At first, we adjust the shape of the section of decline, which removes the section of linear decline and replaced by the section of curve decline; secondly, we adjust the parameter in the decline section. Through the two steps before, the spectrum isn＇ t much too conservative, also the difficulty and the workload are both greatly reduced. The adjustment for the damping-ratio above 5% is considered differently to the adjustment for the damping-ratio below 5%.