车辆行驶速度对连续刚构桥动力特性影响分析

THE INFLUENCE OF VEHICLE SPEED ON DYNAMIC CHARACTERISTICS OF CONTINUOUS RIGID FRAME BRIDGE

文以某连续刚构桥为工程背景,在不同类型车辆以不同车速通过桥面时,对结构进行动力特性分析。利用有限元软件Midas/Civil 2015建立结构动力分析模型,并进行模态分析得到该桥固有频率和振型,通过时程分析,得出该桥在移动荷载作用下跨中位置的动力响应,包括位移、速度和加速度。根据结构的动力响应和对比车辆行驶速度对结构动力响应的影响得到如下结论:当车辆速度相同时,随着移动荷载轴重的增加,位移和加速度响应也相应增大。三种不同轴重车型以不同速度在桥面上行驶时位移、速度及加速度响应均出现了两个波峰,并非是车辆速度越大,动力响应就越大,这为该类桥梁设计和动力性能研究提供参考。

In this paper,a continuous rigid frame bridge is used as the engineering background,and the dynamic characteristics of the structure are analyzed when different types of vehicles pass through the bridge at different speeds. Using finite element software Midas/Civil 2015 structural dynamic analysis model is established,and the inherent frequency and vibration modal analysis for the bridge type,through the time history analysis,it is concluded that the bridge under moving load across the location of the dynamic response,including the displacement,velocity and acceleration.According to the dynamic response of structure and compare the vehicle speed on the influence of structure dynamic response to get the following conclusion: when the vehicle speed at the same time,With the increase of the movable load axle,displacement and acceleration response also increases accordingly. Three different axle load models with different speed in bridge deck on the displacement,velocity and acceleration response appeared two peaks,is not the vehicle speed,the greater the dynamic response,which provide reference for this kind of bridge design and performance research.