钢管拱桥受力行为分析及模型试验若干测试技术研究

发布时间：2018-06-19 13:21

本文选题：钢拱桥 + 模型试验　；参考：《浙江大学》2014年硕士论文

【摘要】：为了减少钢管混凝土拱桥事故给人们带来的生命和财产损失,有必要对钢管混凝土拱桥的健康状况进行监测和评估。桥梁响应(应变、索力、位移)是反映钢管混凝土拱桥健康状况的重要参数。传感器是获取这些监测参数的最直接工具。传统传感监测技术在实际桥梁应用中已暴露出耐久性差、测量精度低、采样频率低、容易受环境因素干扰等诸多问题,桥梁工程领域亟需最新的传感技术能解决这些暴露出的问题。本文以一座中承式钢管拱桥模型为试验平台把不断更新和发展的高新传感技术应用于桥梁监测试验模型。主要研究工作如下： (1)根据试验研究和浙江大学卓越土木工程师平台的一般要求,结合一座实际钢管混凝土拱桥,设计制作一座钢管拱桥试验模型,并对其设计构思、关键技术、施工工序和设计细节等进行详细介绍,分析了钢管拱桥模型组成构件的强度、刚度及稳定性。 (2)对钢管拱桥模型进行有限元静、动力行为分析,得出了在成桥状态和移动车辆荷载作用下,拱肋和纵横梁截面的理论内力、应力和变形等特点以及钢管拱桥模型的频率和振型。对钢管拱桥模型进行屈曲稳定性分析,验证了钢管拱桥的整体稳定性满足试验最大加载工况的要求。 (3)对钢管拱桥模型进行静、动力试验测试研究,并将试验测试结果与数值模拟分析理论值进行对比分析,表明光纤光栅应变传感器具有测量精度高、灵敏度大、测试不受电磁干扰等优点。模型试验实测一阶频率和数值模拟求出的一阶频率的吻合较好,误差为4.1%。 (4)高阶振型对拱桥动力响应分析的影响不可以忽略,对拱桥有必要进行非线性时程分析,钢管拱桥模型的风撑和拱上刚性横梁绕纵桥向的扭转振型出现在第一阶振型,所以,合理选取中、下承式拱桥拱上横向连接构件的竖向刚度是拱桥设计的关键。 (5)将光纤光栅传感器用于钢管拱桥模型的吊杆索力测试,索力测试结果表明光纤光栅传感器具有良好的线性关系,能够准确地获得索力的信息,且光纤传感器采样频率高,其频率能达到上千赫兹,能很好的用于受高速车辆荷载作用的拱桥吊杆索力监测。 (6)将基于相关匹配算法的机器视觉位移监测系统应用在钢管拱桥模型的拱肋挠度和纵梁变形监测,通过在不同工作距离和不同工作角度条件下机器视觉结构位移监测系统的监测试验,表明该系统以1/100毫米级的精度实现拱桥模型结构动态位移测量,在土木工程结构位移/挠度监测中具有重要应用前景。
[Abstract]:In order to reduce the loss of life and property caused by concrete filled steel tube (CFST) arch bridge accident, it is necessary to monitor and evaluate the health condition of CFST arch bridge. Bridge response (strain, cable force, displacement) is an important parameter to reflect the health of CFST arch bridge. The sensor is the most direct tool for obtaining these monitoring parameters. The traditional sensing monitoring technology has exposed many problems such as poor durability, low measurement precision, low sampling frequency, easy to be disturbed by environmental factors and so on. The bridge engineering field urgently needs the newest sensing technology to solve these exposed problems. In this paper, a through-through steel tube arch bridge model is used as a test platform to apply the updated and developed high-tech sensing technology to the bridge monitoring test model. The main research work is as follows: 1) according to the experimental research and the general requirements of the excellent civil engineer platform of Zhejiang University, combined with a practical concrete-filled steel tube arch bridge, a test model of the steel tube arch bridge is designed and made. The design conception, key technology, construction procedure and design details are introduced in detail, and the strength, stiffness and stability of the components of the steel tube arch bridge model are analyzed. Based on the analysis of dynamic behavior, the theoretical internal forces, stresses and deformations of arch ribs and longitudinal and transverse beams, as well as the frequencies and modes of the steel pipe arch bridge model, are obtained under the action of bridge completion and moving vehicle loads. The buckling stability analysis of the steel tube arch bridge model proves that the overall stability of the steel tube arch bridge meets the requirements of the maximum loading condition of the test. By comparing the experimental results with the theoretical values of numerical simulation, it is shown that the fiber Bragg grating strain sensor has the advantages of high measurement accuracy, high sensitivity and no electromagnetic interference. The measured first-order frequency of the model test is in good agreement with the first order frequency obtained by numerical simulation, and the error is 4.1. The influence of high-order modes on the dynamic response of the arch bridge can not be ignored. It is necessary to carry out nonlinear time-history analysis for the arch bridge. Wind brace of steel tube arch bridge model and torsional mode of rigid cross beam on arch appear in the first order mode, so, in the reasonable selection, The vertical stiffness of the transverse connecting member on the arch of the through arch bridge is the key to the design of the arch bridge. 5) the fiber Bragg grating sensor is used to test the cable force of the suspension rod of the steel pipe arch bridge model. The results of cable force measurement show that the fiber Bragg grating sensor has a good linear relationship and can accurately obtain the information of the cable force, and the sampling frequency of the fiber optic sensor is high, and its frequency can reach thousands of hertz. The machine vision displacement monitoring system based on correlation matching algorithm is applied to the monitoring of arch rib deflection and longitudinal beam deformation of steel pipe arch bridge model. The dynamic displacement measurement of arch bridge model structure is realized with the accuracy of 1 / 100 mm by the monitoring test of displacement monitoring system of machine vision structure under different working distance and different working angle. In civil engineering structure displacement / deflection monitoring has an important application prospects.
【学位授予单位】：浙江大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U448.22;U441;U446

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