一致激励下大跨度连续钢桁架柔性拱桥空间地震响应分析

发布时间：2018-05-05 12:15

本文选题：铁路桥梁 + 钢桁架拱桥　；参考：《铁道建筑》2017年11期

【摘要】：基于多自由度空间结构体系地震响应分析的基本理论,利用ANSYS建立空间有限元模型,采用动力时程分析法分析一座大跨度连续钢桁架柔性拱桥在一致激励不同地震工况作用下的空间地震响应。研究结果表明:一致激励作用下,拱肋轴力、主桁弯矩峰值均出现在拱脚和边墩附近,拱肋横向位移峰值出现在每跨拱顶截面,纵向位移峰值沿桥长变化平缓;横向激励对横向位移影响大,对纵向位移影响小,纵向激励对纵向位移影响较大,对横向位移影响较小,竖向激励对水平位移影响较小;地震波组合输入对结构内力影响较单向输入大。建议在大跨度连续钢桁架柔性拱桥抗震设计中充分考虑地震空间特性,提高桥梁横向刚度,优化拱脚、边墩附近结构设计。
[Abstract]:Based on the basic theory of seismic response analysis of multi-degree-of-freedom spatial structure system, the spatial finite element model is established by using ANSYS. The spatial seismic response of a long-span continuous steel truss flexible arch bridge subjected to uniform excitation under different seismic conditions was analyzed by using dynamic time-history analysis method. The results show that under uniform excitation, the peak values of axial force and main truss moment of arch rib appear near arch foot and side pier, the peak value of transverse displacement of arch rib appears in the section of arch top of each span, and the peak value of longitudinal displacement changes gently along the length of bridge. The influence of transverse excitation on lateral displacement is greater than that on longitudinal displacement, longitudinal excitation has greater influence on longitudinal displacement, and vertical excitation has less effect on horizontal displacement. The influence of seismic wave combination input on the internal force of the structure is greater than that on the unidirectional input. It is suggested that seismic spatial characteristics should be fully taken into account in the seismic design of long-span continuous steel truss flexible arch bridge, so as to improve the lateral stiffness of the bridge and optimize the structure design near the arch foot and side pier.
【作者单位】：兰州交通大学甘肃省道路桥梁与地下工程重点实验室;兰州交通大学土木工程学院;
【基金】：国家自然科学基金(51368031) 甘肃省基础研究创新群体项目(1506RJIA029)
【分类号】：U442.55;U448.22

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