摘要
以某独塔自锚式悬索桥为工程背景,采用空间有限元程序ANSYS,对其进行了地震反应仿真计算。针对桥塔和桥墩为异形结构(贝壳状弧形壳体),采用8节点实体单元模拟主塔和桥墩。通过迭代计算确定结构初始平衡状态并计入初应力对结构刚度的影响,建立了全桥精细有限元模型。分别对嵌固模型、考虑桩-土相互作用和考虑承台土压力这3种模型进行了不同地震波组合下的动力时程反应分析。计算结果表明:塔根截面的应力水平最高,是结构抗震的关键部位;墩和塔出现了局部应力集中的现象,应力集中的区域在截面突变处和截面的角点处;考虑承台土压力的影响,可以有效减小桩基础的应力;精细有限元模型可以较好地反映结构在地震作用下的易损部位。
Taking a real bridge as an example, seismic response characteristic of self-anchored suspension bridge with single-tower was studied by spatial nonlinear finite element program （ANSYS）. Because tower and piers were deformed shelly structure, 8-node solid element was used to simulate tower and piers. The elaborate finite element model of whole bridge was established after considering that the change of structural stiffness by initial stress and the initial balance status was obtained by iterative calculation. Three models were set up, including the built-ln edge model, the pile-soil interaction model and the model considering the interaction among pile-support, pile and soil. Different seismic wave superpositions were also considered in dynamic time-history analysis. The results show that stress level of the bottom of tower is highest; stress concentration appears in tower and piers; the regions occurring with stress concentration are angular point of cross-section and places with abrupt change of cross-section; the stress of pile foundation can be reduced efficiently if the interaction between pile-support and soil is considered; the vulnerable part of bridge can be judged by elaborate finite element model. 3 tabs, 16 figs, 12 refs.
出处
《长安大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2008年第1期66-71,共6页
Journal of Chang’an University(Natural Science Edition)
基金
国家自然科学基金项目(50478112)
关键词
桥梁工程
自锚式悬索桥
地震反应
有限元
仿真
bridge engineering
self-anchored suspension bridge
seismic response
finite element
simulation
