结合大跨、高墩、长联曲线铁路梁桥的工程实例,利用大型通用有限元软件ANSYS,采用反应谱的分析方法,给出了该桥在不同的曲线半径、桥墩墩高、墩梁约束方式下的自振频率和振型,分别按纵桥向和横桥向的激励方式,分析了中跨跨中位移,墩顶位移及墩底弯矩随设计参数变化的规律.结果表明:自振频率受桥墩墩高和墩梁连接方式的影响较大,受曲线半径的影响较小；曲线半径在一定范围内变化时,地震响应变化较小；在纵向反应谱的作用下,桥墩墩高的改变对地震响应的变化规律比较复杂,在横向反应谱的作用下,地震响应有一定的变化规律；墩梁约束方式为约束7的地震响应最小,但综合考虑温度、制动力学因素,应该是原设计约束5最优.%According to a long-span,high-pier and multi-span curve bridge,it is calculated the natural vibration frequencies and vibration modes in different curve radiuses,the height of pier and different pier-beam constraint ways were calculated by the finite element software of ANSYS.Using the method of response spectrum,the rules varying along design parameters were obtained from the internal force of pier bottom,the displacement of pier top and girder in the middle span by longitudinal and transversal incentive ways respectively.The results show that the pier height and pier-beam constraint ways have a big influence on the natural vibration frequencies,but curve radiuses have lesser effect; curve radiuses changing in a certain range have a small influence on the seismic response ; in the longitudinal response spectrum,the change rules of seismic response varying along the height of piers is complex,in the transversal response spectrum,the seismic response has certain changes in law ; the seismic response of the constraint 7 of pier-beam constraint ways is the lowest,but overall consideration of temperature and braking mechanics,the original design constraint 5 is optimal.
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