某廊桥工程大震下的地震反应研究

Study on seismic response of some gallery bridge under great earthquake

廊桥结构是具有通行与休憩功能的桥梁结构,由于结构布置不均匀造成桥梁刚度变化很大。罕遇地震荷载作用下其安全性能研究很少,本文采用EPDA程序基于塑性铰理论建立杆件非线性分析模型,对某廊桥进行弹性与弹塑性时程反应分析,通过输入不同地震动以及输入方向的改变,分析廊桥结构的纵向与横向薄弱部位以及梁柱杆件屈服的顺序及塑性铰分布。分析结果表明,设置橡胶隔震支座的廊桥结构能够满足罕遇地震作用下结构延性与承载力要求,但其锁口梁破坏严重,应进行加强,同时建议对桥下部结构框架角部设置竖向腋。

Gallery bridge is a bridge structure which has the function of communication and rest. Because the structure distribution is non-uniform in the bridge,the stiffness has great variation. It is very few to research the seismic security of this kind of building under rare earthquake action. In this paper,based on plastic hinge theory,the EPDA program was used to carry out the members nonlinear analysis. The structure time history analysis was done for some gallery which contains the elastic analysis and the elasto-plastic analysis. For the different ground motion and different input direction,the weak places,the yield sequence,and plastic hinge distribution of beams and columns in longitudinal direction and transverse direction. Analyses show that,the gallery bridge with laminated rubber bearings has the ability to accommodate the requirements of bearing and ductility. Howerer there are many serious damage in locking beam which should be strengthened,and it needs vertical haunch in the corner of the frame structure of bridge.