【作者】 孙松松；

【导师】 单德山；

【作者基本信息】 西南交通大学 ， 桥梁与隧道工程， 2013， 硕士

【摘要】 根据设计图纸,基于有限元理论,可以建立桥梁结构的有限元模型,然而由于模型的结构误差、参数误差和阶次误差,使得该模型不能真实反映桥梁结构的实际工作状态,即有限元模型与实际结构之间存在误差,造成有限元模型计算响应与结构的实测响应不能很好地吻合,为确保有限元模型计算结果能真实反映实际的桥梁结构,应对其有限元模型进行修正随着中国桥梁水平的发展和建设需求,吊拉组合桥梁必将在今后超大跨度桥梁设计中更加具有竞争力,与此配套的健康监测系统的研究也正在开展。有限元模型修正是建立智能化桥梁健康监测系统不可缺少的一个环节,因此对吊拉组合桥梁进行有限元模型修正研究是必不可少的。此外,吊拉组合桥梁的有限元模型修正研究还可为其他类型的桥梁有限元模型修正研究提供参考。主要完成的工作包括：1、对国内外有限元模型修正的研究现状进行了概述,简单介绍了一些常用的模型修正方法,分析这些方法的优缺点、存在的问题,并最终选择响应面法作为有限元模型修正方法；2、对响应而法的概念进行了介绍,给出了基于响应面法的有限元模型修正的步骤以及实现过程,重点介绍用于求解此类约束优化问题的序列：二次规划法和遗传算法的基本知识及其实现过程；3、对某室内吊拉组合桥梁的加劲梁梁段连接及损伤模拟进行了研究,为该桥的模型修正及损伤识别研究奠定了基础；4、依据设计图纸建立了该桥两种损伤工况下的初始有限元模型,利用模型试验实测的桥梁结构响应,对该吊拉组合桥梁进行有限元模型修正,结果表明修正后的有限元模型计算响应和实测响应吻合较好。更多还原

【Abstract】 Based on the finite element theory, the finite element model of the bridge structure can be built according to the design drawings. However, as a result of the model structure error, model parameter error and model order error, the model can’t reflect the actual working state of the bridge structure, it means that some error exists between the finite element model and the actual structure, resulting in that the computing response of the finite element model and the measured response of the structure can not match well. To ensure that the calculation results of the finite element model can truly reflect the actual bridge structure, modification should be made for the finite element model.Along with the development and construction requirements of the bridge in China, the combined cable-stayed suspension bridge will be more competitive in the design of large span bridges in the future, the research of the corresponding health monitoring system is being carried out. Finite element model updating is an indispensable process to establish intelligent bridge health monitoring system, so the finite element model updating research of combined cable-stayed suspension bridges is necessary. In addition, the finite element model updating research of combined cable-stayed suspension bridges can also provide a reference for the finite element model updating research on the other types of bridge.The main work accomplished in this paper, including:Firstly, the current research of finite element model updating at home and abroad are reviewed, some common model modification methods are simply introduced, The advantages and disadvantages of these methods are analyzed, ultimately the response surface method is chosen as the finite element model updating method in this paper.Secondly, the theory of the response surface method is introduced, the steps and implementation process of the finite element model updating based on the response surface method is given, the basic knowledge and its realization process of the sequential quadratic programming method and genetic algorithm method is introduced, which is used to solve this constraint optimization problem.Thirdly, the stiffening girder connection and damage simulation of one combined cable-stayed suspension bridge is researched, to lay the foundation of the research on model modification and damage identification.Finally, the initial finite element model of the bridge’s two damage condition is established according to the design drawings, the finite element model updating of the combined cable-stayed suspension bridge is accomplished, according to the measured response of bridge structure based on the model test. Results show that after the modification, the computing response of the finite element model and the measured response of the structure can match well.更多还原