铁路高桥墩的非线性动力分析

Study on the Nonlinear Dynamic Behavior of Tall Piers of Railway Bridge

以铁路高桥墩为研究对象 ,导出了计轴力及内力素方向改变所致非线性项的高桥墩振动偏微分方程。在分析方程定解条件的基础上 ,讨论了高桥墩架梁前后的振动频率和墩顶位移的变化规律 。

The nonlinear partial differential equations for the tall pier vibration of railway bridges are derived by taking the influence of geometric nonlinearity into consideration, i.e., considering the nonlinear term caused by the direction change in axial forces and internal forces. Based on the analysis of the solution conditions of the equations, the vibration frequencies of a tall pier before and after erecting the bridge beam, and the displacement changing pattern of the pier top are discussed. And the obtained results are compared to those by linear analysis and by the nonlinear analysis of the forced vibration on a non autonomous system.