基础弹性刚度变化对铁路简支梁桥地震响应的影响研究

Study on Variation Effect of Foundation Elastic Stiffness to Seismic Responses of Railway Simply Supported Beam Bridge

以某特大铁路简支梁桥为例 ,考虑m值变化对基础弹性刚度的影响 ,笔者建立了铁路简支梁桥单墩有限元计算分析模型 ;运用大型通用软件ANSYS ,采用时程分析方法 ,对不同地震输入激励条件下的桥墩动力响应进行计算研究 ;研究结果表明 ,m值变化引起的基础竖向刚度的变化对桥梁结构地震响应的影响较大。笔者的研究成果为硬土质基础的铁路简支梁桥的抗震安全设计 ,提供了重要参考。

Considering the effect of m value on the foundation stiffness, the single-pier analysis model for finite element of railway simply supported beam bridge is established. The dynamic responses of the piers under different seismic excitations are calculated in general FEA software ANSYS by time-history method. The results indicate that the variation of vertical foundation stiffness has much influence on bridge seismic responses. The study provides the meaningful reference for anti-seismic safety design for railway simply supported bridge on hard-soil foundation.