【摘要】 本文讨论了日本第一座公路钢管混凝土拱桥——主跨230m的新西海桥的非线性地震响应特性。采用三维有限元计算模型,用纤维单元法考虑钢管混凝土的材料非线性,用P-δ效应考虑几何非线性,讨论了在纵桥向地震作用、横桥向地震作用以及纵、横桥两方向同时作用情况下该桥的非线性地震响应特性和抗震性能。计算表明,在纵桥向地震作用时轴力的作用显著,拱脚附近产生的内力较大;而横桥向地震作用时轴力和面外弯矩作用显著,拱脚以及拱肋与桥面连接附近产生的内力较大;横向地震响应远大于纵向地震响应;应考虑纵、横桥向地震力共同作用的影响。更多还原

【Abstract】 This paper examines the nonlinear seismic responses of New Saikai Bridge,which has a main span length of 230 m and is the first CFT arch bridge of highway bridges in Japan.Using a three-dimensional FE model,in which the fiber model is used to consider the material nonlinearity and the P-δ effect are used to consider the geometric nonlinearity.The nonlinear seismic characteristics and seismic performance of this bridge are examined in detail by subjecting the bridge to strong earthquakes in the out-of-plane direction,the longitudinal direction,or the combined out-of-plane and longitudinal directions.It is shown that: the axial forces are predominant when subjected to an earthquake in the out-of-plane direction;the axial forces and out-of-plane bending moments are predominant when subjected to an earthquake in the longitudinal direction;the responses subjected to earthquake in the out-of-plane direction are larger than those in the longitudinal direction;the effect of the combined out-of-plane and longitudinal excitations should be considered.更多还原