考虑群桩基础柔度的梁拱组合桥静动力分析与试验

Static and Dynamical Analysis and Test of a Beam-Arch Combinated System Bridge Considering the Flexibility of Pile-Group Foundation

以九天湖大桥工程为背景,提出了一等代群桩基础空间柔度的四柱空间刚架模型,推导了该空间刚架几何参数的计算公式。将"m法"计算的该桥群桩承台的柔度代入计算公式得到了等代刚架的几何参数。据此采用Ansys软件建立了该桥考虑群桩基础柔度的实体模型进行静动力分析,并进行了成桥静动载试验。理论分析结果和试验结果对比分析表明本桥具有良好的静动力性能,且本文采用的等代空间刚架能准确的反映群桩基础的柔度,计算模式合理。

The paper suggests a space rigid frame model which is equivalent to the space flexibility of pile--group foundation in the background of Nine days Lake Bridge project. The formulas to caculate the geometrical parameters of the space rigid frame model were deduced. The flexibility of pile--group foundation of the bridge was caculated by ＂m method＂, then the geometrical parameters was got by taking the results to the formulas. Static and dynamical analysis were carried out with a solid model by cosidering flexibility of pile--group foundation which was built by Ansys software. Finally static and dynamical tests were carried out. The contrast between theoretical results and test results indicated that the bridge has good static and dynamical performance and the sapce rigid frame can simulate the flexibility of pile--group foundation exactly.