弹性支承条件下车-桥体系的振动分析

本文研究弹性支承条件下车-桥体系的动力分析方法。给出了弹性支承桥梁和车体的振动方程并通过对具有弹性支座简支梁主振动的分析，得出了梁主振型的解析公式。分析计算了上海高架轨道交通典型区段具有弹性支座高架梁的主振型，并利用龙格-库塔法分析计算了车-桥体系在列车通过时的桥梁和车体的振动。计算结果表明，在上海高架轨道交通实际计算参数条件下，考虑支座弹性后桥梁和车体的振动与刚性支承梁的情况相比变化不明显。本文还计算分析了不同橡胶减震支座的刚度及考虑减震支座后系统阻尼比增大等因素对高架梁振动反应的影响，得出一些有益的结论。

Dynamic Analysis of Train-bridge System with Elastic Supports

The dynamics of train-bridge system with elastic supports was studied. The principal vibration of a simple beam with elastic supports was analyzed and the analytical formulation of normal vibration mode was derived. Based on the parameters of typical beam of viaduct rail transit in Shanghai, using the normal vibration mode and Runge-Kutta method, the vibration of train-bridge system with elastic supports at the train passing was analyzed. Under the practical conditions of numerical example, the calculated result shows that the vibration of train-bridge system with elastic supports is not rather deferent from that of train-bridge system with rigid supports. The effects of the stiffness of bearing isolations and the system damping on vibration of bridge were also analyzed.