高层结构阻尼比取值对地震响应的影响规律及减震设计思考

Influence law of high-rise structure damping ratio on seismic response and design discussion of seismic energy dissipation

基于某实际工程案例,通过设置不同的计算模型,深入分析了阻尼比取值对高层结构地震响应的基本影响规律特征,在此基础上讨论了计算方法的合理选用以及消能减震设计的相关问题。结果显示,时程分析法与反应谱法两种方法反映出的阻尼比对地震响应的影响呈现较大差异性,通常时程分析法能获得更加显著的地震响应降低效果,并且这种差异性与结构的基本周期密切相关,基本周期越大则差异程度越大。讨论了脉冲型地震动对阻尼的敏感性,结果表明提高阻尼对脉冲型地震动输入响应的“削峰”作用不明显,阻尼作用更多体现在对后续振动衰减速度的影响上。最后提出一种新的减震计算分析流程,并建议了以位移为减震目标时的消能减震设计应对策略。

Based on an actual project case, through setting different calculation models, the basic characteristics of the influence of damping ratio value on the seismic response of high-rise structure was studied in depth, on the basis of this, the reasonable selection of calculation method and the related problems of seismic energy dissipation design were discussed. The results show that the influence of damping ratio reflected by time history analysis and response spectrum analysis was quite different, and time history analysis method could obtain more significant reduction effect of seismic response, and the difference was closely related to the basic period of the structure. The greater the basic period is, the greater the difference is. The sensitivity of impulse ground motion to damping was discussed and the results show that the "peak clipping" effect of increasing damping was not obvious as to the response of impulse ground motion, and the damping effect was reflected in the influence on the subsequent vibration attenuation speed. Finally, a new calculation and analysis process of seismic energy dissipation was proposed, and the design strategy of seismic energy dissipation was proposed when the displacement was taken as the target.