基于实测随机车流样本的桥梁冲击系数谱研究

发布时间：2018-07-01 12:30

本文选题：随机车流 + 车-桥耦合　；参考：《长安大学》2014年硕士论文

【摘要】：桥梁结构的动力特性是评价桥梁设计参数是否合理的一个重要方面，冲击系数是桥梁结构动力特性的重要参数之一，本文基于随机车流-桥梁耦合振动分析系统研究了不同车型车速变化时对冲击系数的影响、典型车型以不同装载量过桥对桥梁冲击系数的影响，以一座六跨连续T梁桥为对象计算随机车流作用下桥梁响应和冲击系数谱，，选择高速公路五种典型跨径简支T梁桥研究特重车流作用下冲击系数谱、并引入路面粗糙度修正系数提出桥梁冲击系数合理取值的计算方法。主要研究内容如下： 1．根据采集到的24小时随机车流数据将高速公路常见车型划分为17种，对车型、车速、车重及横向行驶位置等参数进行统计分析，以一座六跨连续T梁为工程背景计算随机车流下桥梁静动力响应，形成冲击系数谱，分析冲击系数谱的分布规律及其与车速、车重、主梁内力之间的关系。 2．研究了不同车型以不同行车速度通过桥梁时冲击系数的变化规律，并选择对桥梁冲击系数影响较大的几种典型车型，建立不同载重量的行车工况，研究典型车型不同车重作用对桥梁冲击系数的影响。 3．选择高速公路五种典型跨径简支T梁桥，建立了特重车流样本，计算特重车流作用下不同跨径桥梁静动力响应，形成特重车流桥梁冲击系数谱，研究桥梁冲击系数谱与车辆荷载静力效应的关系并引入设计荷载效应作为对比，对冲击系数谱进行优度拟合检验，计算在置信度95%水平下桥梁冲击系数取值，研究冲击系数取值与桥梁跨径、桥梁基频之间的关系，最后考虑路面粗糙度影响提出桥梁冲击系数的合理取值方法。
[Abstract]:The dynamic characteristics of bridge structure is an important aspect to evaluate whether the design parameters of bridge are reasonable or not, and the impact coefficient is one of the important parameters of dynamic characteristics of bridge structure. Based on the random vehicle-bridge coupling vibration analysis system, this paper studies the influence of different vehicle speed on the impact coefficient, and the influence of the bridge crossing with different loading capacity on the bridge impact coefficient. Taking a six-span continuous T-beam bridge as an object to calculate the response and impact coefficient spectrum of the bridge under the action of random traffic flow, five typical span simply supported T-beam bridges are selected to study the impact coefficient spectrum under the action of extra heavy vehicle flow. A reasonable calculation method of bridge impact coefficient is put forward by introducing road roughness correction coefficient. The main research contents are as follows: 1. According to the data of 24 hours random traffic flow, the common vehicles are divided into 17 types, and the parameters such as vehicle type, speed, vehicle weight and lateral driving position are statistically analyzed. The static and dynamic responses of a six-span continuous T-beam under random traffic flow are calculated to form the shock coefficient spectrum. The distribution law of the impact coefficient spectrum and its relationship with vehicle speed and vehicle weight are analyzed. 2. Study the change rule of impact coefficient when different vehicle type passes through bridge with different driving speed, and select several typical models which have great influence on bridge impact coefficient. The influence of different vehicle weight on the impact coefficient of the bridge was studied. 3. Five typical span simply supported T-beam bridges were selected and the special weight vehicle flow samples were established. The static and dynamic responses of bridges with different spans under the action of extra heavy vehicle flow are calculated to form the impact coefficient spectrum of super heavy vehicle flow bridges. The relationship between the impact coefficient spectrum of the bridge and the static effect of vehicle load is studied and the design load effect is introduced as a comparison. The impact coefficient spectrum is tested by goodness fitting, and the bridge impact coefficient is calculated at 95% confidence level, and the relationship between the impact coefficient value and bridge span and bridge fundamental frequency is studied. Finally, considering the influence of road roughness, a reasonable method of bridge impact coefficient is put forward.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U441.3

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