导 师: 黄平明;韩万水
学科专业: H1406
授予学位: 博士
作 者: ;
机构地区: 长安大学
摘 要: 公路交通荷载调查是确定新桥设计荷载、桥梁时变可靠性分析、既有桥梁剩余寿命预测、极限承载能力计算以及随机车流仿真模拟等研究的重要基础之一。随着汽车工业和交通运输行业的迅速发展,车辆荷载较以往发生了很大的变化,交通运输的重心也由国、省道全面向高速公路转变。然而由于目前高速公路交通荷载调查方面基本处于初始研究阶段,系统深入的研究工作较少。因此,选择一条高速公路开展系统全面的交通荷载调查,确定交通荷载的各关键参数,合理地确定车辆荷载模型具有非常重要的意义。 本文通过对西宝高速虢镇桥梁现场交通量调查,全面系统的研究了高速公路交通荷载各参数的随机特性及统计规律,提出一种基于有限元模型修正的多梁式桥梁移动荷载识别方法,编制了随机车流仿真模拟程序,建立更符合实际的仿真车流模型。主要研究内容表现在以下几个方面: 1、提出了一种全面观测高速公路交通荷载各要素的调查方法,采用超声波测速仪、录像机及桥梁动态测试仪同人工记录相结合的方法对高速公路桥梁的交通荷载状况进行24小时连续观测调查,记录的数据包括车型、车辆数目、车速、行驶车道、车辆到达时间以及车辆通过时桥梁的动力响应。对得到的交通荷载样本进行详细分析,获得以上各参数随时段变化规律及分布特征,建立交通荷载参数数据库。 2、以批量识别过桥车辆的车重参数为目的,对采集的交通荷载作用下桥梁动位移响应数据以车型为单位归类统计分析,获取全部交通荷载及各车型交通荷载作用下桥梁响应特征。 3、介绍了多主梁车桥耦合振动分析思路,编制相应分析模块,在此基础上编制了程序界面、前后处理系统以及动力响应行为动画演示系统。最后通过工程实例对该模块的可靠性和有效性进行了验证。 4、以有限元模型修正、低通滤波器设计以及多梁式车桥耦合振动程序为基础,提出了基于有限元模型修正的多梁式桥梁移动荷载识别方法。通过试验对该方法的可靠性和识别精度进行了验证。最后利用该识别方法按车型分类批量识别出本次调查中所有单车过桥车辆的横向位置及车重参数,并进行统计分析。 5、通过Monte-Carlo方法建立交通流数学模型,借助Matlab软件的程序语言及界面,编写出可视化的高速公路随机车流仿真模拟程序,生成基于交通荷载实测数据的仿真车流。最后将模拟车流样本与调查样本的各参数进行对比分析,检验了本随机车流仿真程序的有效性及准确性。 The investigation of the traffic loading are the basis on which the following studies such as the designed loading, the time-variant bridge reliability analysis, the life expectation of the existing bridge, the ultimate capacity calculation and the random traffic flowing simulation are based. With the rapid development of the vehicle industry and the transportation business, a major change has occurred on the traffic loading, and the expressway have gradually play more and more important roles than the roles that the national highway and province highway had played before. However, the traffic loading investigation for the expressway is just on the preliminary stage, and there is few related studies. Therefore, it is rather important to conduct a real time and extensive investigations on the traffic flowing of a real expressway for this study in that most of the related characteristics of the traffic flowing as well as the related key parameters can be captured. In this thesis, With the collected traffic loading data from one bridge of Xi-Bao expressway, the stochastic characteristics of the related parameters of the traffic loading of the expressway are studied systematically and extensively, One moving loads identification approach for the multi-girder bridge, based on the calibrated FEM model, is presented. Then another specified program is employed to create the simulated vehicle model so that all the stochastic parameters will agree well with the realistic ones. The main research contents and conclusions are as follows: 1. A methodology, capable of investigating all the critical parameters of the traffic loading on the expressway, is presented. For this approach, the speed radar gun, the video recorder, and the dynamic strain tester are for the first time being employed in combination with manually recordering to detailed investigate the traffic loading on the expressway bridge. With this approach, the vehicle type, speed, traffic lane, the arriving time of the traffic and the bridge-vehicle dynamic interaction are all recorded. Then based on the captured traffic loading samples within 24 hours, through the detailed analysis, the statistic distribution features and the variations of all the data listed previously with time are obtained, then the parameters database for the traffic loading is built。 2. Aimed at batch identification of vehicles weight parameter, the collected data with regard to the dynamic displacement response to the traffic loading is statistically analyzed and classified by vehicle type, then the dynamic response characteristics of bridge subjectd to each type of traffic loading is obtained. 3. The analytical methodology governing the vehicle-bridge interaction analysis for the multi-girder bridge is introduced, the related analytical modules is programmed. Then, an interface, the preprocessor and the postprecessor and the animation demonstration system are programmed as well. Finally, by a real example, the reliability and the efficiency of the modules are verified. 4. Based on the calibrated FEM, the low pass filter and the vehicle-bridge interaction analysis program specialized for the multi-girder bridge,the moving loads identification method applied for the multi-gider bridge is presented. Compared with the real bridge loading test, it is substantiated that the proposed identification method is reliable and accurate. Finally by the use of such identification method, classified by the vehicle type, the transverse location and the vehicle weight parameter corresponded with each running single vehicle in this investigation is obtained, on the basis of which,the statistical analysis is conducted. 5. One program is coded, specifically for the random traffic loading simulation for the expressway bridge, using Monte-Carlo numerical simulation method and Matlab. Comparing with the real traffic sample, the simulation made by this program is accurate and reliable.
关 键 词: 高速公路桥梁 交通荷载 随机车流 统计分析 样本检验 多梁式桥梁 车桥耦合 有限元模型修正 车重识别 仿真模拟
分 类 号: [U4]
领 域: [交通运输工程]