摘要
An accurate finite element （ FE） model was constructed to examine the hysteretic behavior of double-skin steel-concrete composite box （ DSCB） piers for further understanding the seismic performance of DSCB piers; where the local buckling behavior of steel tubes, the confinement of the in-filled concrete and the interface action between steel tube and in-filled concrete were considered. The accuracy of the proposed FE model was verified by the bidirectional cyclic loading test results. Based on the validated FE model, the effects of some key parameters, such as section width to steel thickness ratio, slenderness ratio, aspect ratio and axial load ratio on the hysteretic behavior of DSCB piers were investigated. Finally, the skeleton curve model of DSCB piers was proposed. The numerical simulation results reveal that the peak strength and elastic stiffness decrease with the increase of the section width to steel thickness ratio. Moreover, the increase of the slenderness ratio may result in a significant reduction in the peak strength and elastic stiffness while the ultimate displacement increases. The proposed skeleton curve model can be taken as a reference for seismic performance analyses of the DSCB piers.
为进一步研究双壁钢箱混凝土组合墩柱(DSCB墩柱)的抗震性能,建立了考虑钢管局部屈曲、内填混凝土约束效应和钢管与混凝土接触作用的DSCB墩柱的精细化有限元模型.首先通过双向拟静力试验结果验证了该有限元模型的准确性;然后采用验证后的有限元模型,研究了钢板宽厚比、长细比、截面宽高比、轴压比等关键参数对DSCB墩柱滞回性能的影响;最后根据试验和有限元分析结果提出了DSCB墩柱的骨架曲线模型.数值模拟分析结果表明:随着钢板宽厚比的增大,DSCB墩柱的峰值强度和弹性刚度减小;随着长细比的增加,DSCB墩柱的峰值强度和弹性刚度明显降低,而极限位移则随之增大.所提出的骨架曲线模型可为DSCB墩柱的抗震性能分析提供参考.
基金
The National Natural Science Foundation of China(No.51678141,51378112)
the Open Fund from the National Engineering Laboratory for Technology of Geological Disaster Prevention in Land Transportation,Southwest Jiaotong University(No.SWJTUGGS-2014001)
