轻轨车-轨道梁-刚构桥空间耦合振动分析及乘坐舒适性评价

Analyses on Spatial Vibration of Coupled Monorail Trains,Track Beams and Rigid-frame Bridge and Riding Comfort of Monorail Trains

提出一种跨座式轻轨车、轨道梁及刚构桥空间耦合振动时域分析方法。轨道梁及刚构桥采用常规有限单元模拟,跨座式轻轨车采用弹簧阻尼相连的多刚体模拟,可方便考虑走行轮、导向轮、稳定轮下轨道不平顺影响,每一积分步内对桥梁系统动力方程扩展,建立轻轨车-轨道梁-刚构桥时变系统空间振动方程,采用直接积分法同时求解三者空间动力响应,并编制相应计算分析程序。针对目前世界最大跨度轻轨专用刚构桥96m+160m+96m,探讨车速、单线行车、双线对开等不同工况对三者动力响应影响并对轻轨车进行乘坐舒适度评价。结果表明:在设计行车速度下,乘客可安全舒适通过该桥。该方法可运用于跨座式轻轨车与其它轨道梁或桥梁空间振动分析。

This paper presents an approach to dynamic analysis on the coupled monorail train, track beam and rigid-frame bridge system in the time domain. The monorail train is idealized as a combination of a number of rigid bodies connected by a series of springs and dampers which can easily consider the effect of lateral and vertical surface roughness of tracks under driving, steering, and stabilizing wheels of the monorail train, while the track beam and rigid-frame bridge are represented by the conventional finite elements. The governing equation of motion of the coupled system is assembled by the adoption of fully computerized approach. The direct integration method is used to solve the dynamic responses of the system. The corresponding analytical programme is compiled. A rigid-frame bridge with track beams is taken for case study, which has the longest main span of 160m for the monorail train. Dynamic responses of the system are computed corresponding to the conditions when the monorail train runs through the bridge. Effects of driving speeds and running manners on the dynamic responses of the coupled system are discussed, and riding eomfort of the monorail trains is studied. The reuits show the train can safely and comfortably go through the bridge at the design speed. This approach can also be used to carry out spatial vibration analyses of the monorail train and other longer span bridges.