摘要
斜交桥动力特性复杂、震害多样,准确评估斜交桥地震反应意义重大,尤其在基于性能桥梁抗震设计中,需要对斜交桥三维精细化模型进行非线性地震反应分析。以单跨斜交桥为研究对象,建立考虑桥台非线性特性和双向碰撞作用的桥梁三维精细化有限元模型,开展水平双向近场地震动作用下结构的非线性地震反应分析,研究不同桥台横向约束模型对斜交桥地震反应的影响以及不同斜交角度斜交桥地震反应规律。结果表明:桥台横向约束条件对斜交桥地震反应有较大影响,在抗震性能分析中需对桥台和碰撞作用进行合理考虑;桥台双向碰撞作用对上部结构平面转动的影响显著,且易导致桥台钝角处的回填土失效和锐角处的挡块损伤;斜交桥的碰撞力明显高于直桥,纵向位移和平面转角随斜交角度的增大而增大。
Skew bridges have complex dynamic characteristics and a variety of earthquake damage.It is of vital importance to evaluate the seismic response of skew bridges accurately.It is necessary to analyze the nonlinear seismic response based on the three-dimensional refined model of skew bridges,especially in the performance-based seismic design of bridges.A three-dimensional refined finite element model of a single-span skew bridge considering nonlinear characteristics of skew-angled abutments and the pounding effect between the superstructure and the abutments was established.Nonlinear time history analyses were performed to investigate different transversal restraint models of the abutment on the seismic response of sewed bridges under horizontal near-fault ground motion.The influence of skew angles on the nonlinear seismic response of the bridge was analyzed using seven sets of horizontal two-way near-fault ground motions.The results show that the transversal restraint models of the abutment have a significant effect on the seismic response of skewed bridges,which should be reasonably considered in the performance-based seismic design of bridges.The pounding effect between the deck and abutments both in transverse and longitudinal directions can change the rotation response obviously,and the impact also makes the abutment backfill at the obtuse corner and abutment shear keys at the acute corner fail easily.The pounding force of skewed bridges is higher than that of the straight bridge and the displacement in the longitudinal direction and the rotation response increases with the increase of the skew angle apparently.
作者
陈敬一
王利辉
周雨龙
袁小祥
CHEN Jingyi;WANG Lihui;ZHOU Yulong;YUAN Xiaoxiang(China Earthquake Disaster Prevention Center,Beijing 100029,China;Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education,Beijing University of Technology,Beijing 100124,China;Key Laboratory of Old Bridge Inspection and Reinforcement Technology Industry,Research Institute of Highway Ministry of Transport,Beijing 100088,China;Institute of Earthquake Forecasting,Beijing 100036,China)
出处
《防灾减灾工程学报》
CSCD
北大核心
2022年第6期1314-1323,共10页
Journal of Disaster Prevention and Mitigation Engineering
基金
高分卫星遥感城市高层建筑地震风险评估应用示范项目(31-Y30F09-9001-20/22-09)
基于桥梁地震易损性的路网震后可恢复性评估项目(CEAEDEM202223)资助。
关键词
斜交桥
地震反应
桥台横向约束
双向碰撞
斜交角
skewed bridges
seismic response
transverse constraint of abutment
bi-directional pounding
skew angle
