【摘要】 考虑支座非线性和桥墩弹塑性的影响,建立了不等墩高5跨非规则简支梁桥的有限元模型。采用非线性时程分析方法计算了不同地震波输入下多跨简支梁桥的纵向地震反应,研究了非规则多跨简支梁桥邻跨刚度比及上部结构间相互碰撞效应对桥梁纵向地震位移反应和内力反应的影响规律。研究表明,邻跨刚度比对非规则多跨简支梁桥的桥墩剪力、墩底弯矩、墩顶位移、梁体位移、墩梁间相对位移及主梁间相对位移有着显著的影响,并且邻跨刚度相差越大,影响越为显著,更容易使上部梁体发生落梁破坏;考虑桥梁上部结构碰撞效应时,邻跨比对桥梁结构反应的影响受地震波的影响较大,碰撞未必加剧落梁破坏。更多还原

【Abstract】 Considering the nonlinear behavior of bearings and elastic-plastic behavior of piers,the finite element model of a five-span simply supported girder bridge with unequal pier height is established.The longitudinal seismic responses of bridge due to different seismic waves are calculated by using a nonlinear time-history analysis method.The parameter influence of stiffness ratio of the adjacent span and collision of superstructure on longitudinal seismic displacement and internal force responses of simply supported girder bridge with unconventional configurations is researched respectively.The research shows that stiffness ratio of adjacent span has significant influence on the pier shear force,pier bending moment,top displacement of pier,girder displacement,relative displacement between pier and girder,and relative displacement between girders.With the increase of the difference of dynamic characteristic between adjacent spans,the influence of the adjacent span stiffness ratio on bridge response is more significant and bridge is easy to be unseating failure.Considering the collision effect,the effect of the stiffness ratio of adjacent span on bridge response depends on seismic wave and the collision between girders does not always aggravate the unseating failure.更多还原