【摘要】 对超大跨度结构,地震动空间变化的影响明显存在。两层与三层组合的钢网壳结构是一种可跨越超过150m的空间结构。采用确定性动力分析方法,选取合理的地震动输入模型,在参数分析的基础上研究这类结构在多点输入的地震作用下的反应,比较非一致输入与一致输入下结构响应的差异。分析得到,随着视波速的增加,行波效应对结构影响减小。当视波速大于200m/s时,行波效应的影响已很小,可以按一致地震输入进行设计。结构刚度较大时,多支座的不同步扰动使得结构支座附近的应力较一致输入有较大增加。行波效应使结构的地震反应峰值显著提前。与一致输入结果相比,危险杆件的分布位置及数量有一定变化,设计必须考虑。更多还原

【Abstract】 The performance of super span structures is influenced significantly by the spatial variation of seismic waves.Double and triple layered hybrid steel reticulated shells are spatial structures that can cross over more than 150 meters.The deterministic dynamic analysis method is used.The reasonable seismic wave model is selected.Based on parameter analysis,the response to multi-point seismic input is investigated.The difference between non-synchronous excitation and synchronous excitation is presented.The following results are observed.The traveling wave effect decreases with the increase of traveling wave velocity.When the wave velocity is greater than 200m/s,the influence of traveling wave is very small.In such case,the consistent seismic wave input can be used for structural design.For structures with larger rigidity,the asynchronous disturbance at multiple supports causes great increase of interior forces in the members nearby the supports.The traveling wave effect makes the maximum structural seismic response occur in advance.Compared with the results of uniform seismic wave input,the distribution and the numbers of dangerous member are changed,which need to be considered in structural design.更多还原