某高速铁路连续梁桥桥墩地震反应分析

Analysis of Seismic Performance of Pier of High Speed Railway Continuous Girder Bridge

为深入了解高速铁路地震区桥墩设计的特点,以某客运专线高烈度地震区连续梁桥为研究对象,建立全桥三维有限元模型,计算连续梁桥桥墩的刚度、结构的自振频率及振动模态特性,并采用反应谱法进行地震反应分析。计算结果表明:高速铁路连续梁桥桥墩纵向刚度比横向和竖向刚度小,在8度及以上烈度区,地震力控制桥墩截面的配筋设计,按照纵、横向进行地震效应检算可满足设计要求,也可采用减、隔震等措施来降低桥墩地震力。

In order to have a deep understanding of the design features of high speed railwaybridge piers in earthquake area, a continuous girder bridge on a passenger dedicated railway line in high-amplitude earthquake area is taken as the study object. The 3D finite element model of the overall bridge was established to calculate its pier rigidity, the natural frequen,：y and the traits of vibration mode. Meanwhile, the response spectrum method was adopted to analyze the seismic performance of the bridge. The results of the calculation show that the longitudinal rigidity of the piers of high speed railway continuous girder bridge is lower than the transverse and vertical rigidity in the region of seismic intensity Ⅷ or above, seismic force dictates the design of the rein- forced bars on the pier sections, according to the longitudinal and transverse seismic performance verification, the seismic performance of piers can meet the design requirements, nevertheless, seismic mitigation and isolation measures should be considered and adopted to ：reduce the dynamic response of the pier.