峰值位移输入对单自由度体系地震反应的影响

发布时间：2018-04-21 19:59

本文选题：单自由度体系 + 地震动　；参考：《建筑结构学报》2017年01期

【摘要】：在加速度反应谱与峰值速度不变的条件下,研究输入地震动峰值位移对单自由度体系动力反应、尤其是弹塑性动力反应的影响。利用在时域内叠加窄带时程的方法合成加速度反应谱和峰值速度相同而峰值位移相差1倍的两组人工地震动时程,按照GB 50011—2010《建筑抗震设计规范》的要求,将合成的输入地震动采用不同设防烈度多遇地震的峰值加速度标定,进行体系的弹性分析。结果显示,输入地震动峰值位移的变化对弹性动力反应基本无影响。将输入地震动采用相应烈度罕遇地震的峰值加速度标定,并以上述多遇地震作用下弹性最大位移反应作为罕遇地震作用下结构弹塑性分析的屈服位移,进而分析输入地震动峰值位移变化对弹塑性动力反应的影响规律。结果表明:峰值位移的增大将会明显增大中长周期结构弹塑性位移反应和速度反应,这种放大效应对位移反应尤为显著,其规律在不同设防烈度区具有一致性,即随着设防烈度的提高,输入地震动峰值位移的增大引起的大部分中长周期结构弹塑性位移及速度反应的放大效应减小。因此,在进行结构动力分析时,应充分考虑输入地震动峰值位移变化对计算结果的影响。
[Abstract]:Under the condition of constant acceleration response spectrum and peak velocity, the effect of the peak displacement of input ground motion on the dynamic response of single degree of freedom system, especially the elastoplastic dynamic response, is studied. Using the method of superposing narrow band time history in time domain, two groups of artificial ground motion time history with the same acceleration response spectrum and the same peak velocity and difference of peak displacement are synthesized according to the requirements of GB50011-2010 Code for Seismic Design of buildings. The composite input ground motion is calibrated with the peak acceleration of earthquake with different fortification intensity, and the elastic analysis of the system is carried out. The results show that the change of peak displacement of input ground motion has little effect on elastic dynamic response. The input ground motion is calibrated with the peak acceleration of the corresponding intensity rare earthquake, and the maximum elastic displacement response under the above frequent earthquakes is taken as the yield displacement of the elastic-plastic analysis of the structure under the rare earthquake. The influence of the peak displacement of input ground motion on the elastoplastic dynamic response is analyzed. The results show that the increase of peak displacement will obviously increase the elastic-plastic displacement response and velocity response of medium-long period structures, and this amplification effect is particularly significant for displacement response, and the law is consistent in different fortified intensity regions. That is, with the increase of fortification intensity, the amplification effect of elastic-plastic displacement and velocity response caused by the increase of peak displacement of input ground motion decreases. Therefore, the influence of the peak displacement of the input ground motion on the calculation results should be fully considered in the dynamic analysis of the structure.
【作者单位】：中国地震灾害防御中心;
【基金】：地震行业专项项目(201408020) 地震星火计划项目(XH17052Y)
【分类号】：TU311.3

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