【摘要】 地震地面运动是一复杂的时-空过程,严格来说所有结构的地震反应分析均应考虑地震动空间变异性的影响,尤其是当结构规模和平面尺寸较大时,这种差动效应就更加明显,由此引起的结构反应与一致激励相比有所不同。本文基于相位差谱生成非平稳空间地震动场后,进行了国家体育场在多点激励下的地震反应分析,并将计算结果与一致激励的结果进行了对比。结果显示:水平地震作用下多点激励作用方向上的位移反应多小于一致激励的,多点激励作用下非激励方向的位移大于一致激励的;竖向地震作用下的变形在多点激励时较大。基底剪力和基底弯矩在多点激励作用下的反应较一致激励的小。更多还原

【Abstract】 The earthquake ground motion is a complicated time-space process and may be different at different supports of large-span structures. Significant progress on the relevant issues has been made, and studies on the response of large span structures have shown that the effects of multi-support excitations should be considered. In this paper, the responses of the national stadium of the 2008 Olympic game in Beijing under uniform excitation and multiple support excitations are studied by using the time history analysis method. Spatially variable ground motion time histories are simulated. It is found that the uniform ground motion cannot represent the most critical case for the response of the national stadium structure. The assumption of multiple support excitations may be realistic and result in larger deformation when under vertical earthquake motion and smaller shear force and bending moment at the base.更多还原