公路桥梁高墩施工阶段动力特性分析

Dynamic Property Analysis of High Pier of Highway Bridge During Construction

以国道209线和林格尔至清水河一级公路贾家湾大桥单支空心薄壁高墩施工为背景,通过变分原理推导了结构动力学方程和以有限元为基础的有限自由度的运动微分方程组。借助大型有限元软件MIDAS,并根据单支空心薄壁墩施工过程,建立了空心薄壁墩施工阶段的动力特性有限元计算模型,通过13个模型的计算,分别得到了每一个模型的前5阶固有频率和振型。通过分析各模型的动力参数,找到了一些对单支空心薄壁墩施工的影响因素。

The single hollow thin-wall high pier construction of Jia Jiawan bridge at G209 line from Helingeer to Qingshuihe highway was taken as the background.Through the variational principle,the equation of structure dynamics was deduced,and the motion differential equations of the finite degrees of freedom based on FEM was also deduced.With the help of the finite element analysis software MIDAS,and according to the single hollow thin-wall pier construction process,the finite element calculation model with dynamic property of the hollow thin-wall pier was established.The first 5 order natural frequency and vibration mode of each model was obtained by the 13 model calculation.Through the analysis of the dynamic parameters of each model,some factors which affect the construction of single hollow thin-wall high pier was found.