钢结构桥梁交通荷载特征和正交异性钢桥面板疲劳机理研究

发布时间：2018-04-26 20:35

本文选题：正交异性钢桥面板 + 简化车辆荷载谱　；参考：《天津大学》2014年硕士论文

【摘要】：正交异性钢桥面板是由面板、纵向加劲肋和横隔板组成的共同承受上部荷载的整体结构，以其自重轻、极限承载力大、施工周期短等优点被广泛应用于国内外大跨度桥梁，，但其构造复杂，在车辆循环荷载作用下疲劳问题突出，特别是横隔板与纵向加劲肋相交的构造细节位置，在各国桥梁实例中均发现不同程度的疲劳开裂现象。本文以天津市海河大桥为工程背景，结合桥梁检测报告、现场试验和有限元分析研究正交异性钢桥面板疲劳性能，估算其构造细节疲劳寿命，主要内容包括：（1）现场检测并记录车辆通行过程中海河大桥横隔板应力响应，并同时摄录通行车辆，统计数据，得到简化车辆荷载谱。（2）采用ABAQUS有限元分析软件建立海河大桥钢箱梁节段模型，计算简化车辆荷载谱作用下横隔板测点应力历程，通过雨流法分析与实测应力历程对比，校核简化车辆荷载谱。（3）利用校核后的车辆荷载谱计算海河大桥（有撑杆与无撑杆）构造细节应力应变历程，估算其疲劳寿命。对比设置撑杆前后，海河大桥构造细节疲劳性能的差异。（4）在横隔板子模型中引入初始残余应力，计算横隔板挖孔位置应变历程，考虑平均应力修正，重新估算挖孔位置疲劳寿命。（5）研究易疲劳开裂位置主应力状态在车辆荷载作用下的变化，分析主拉应力方向并与实际开裂方向进行比较；分析主应力幅值变化趋势与横隔板内力变化趋势的相关性。
[Abstract]:Orthotropic steel bridge deck is a whole structure, which is composed of panel, longitudinal stiffener and diaphragm. It is widely used in large span bridges at home and abroad because of its advantages of light weight, large ultimate bearing capacity and short construction period. But its structure is complex and the fatigue problem is prominent, especially the diaphragm under the cyclic loading of vehicles. The structural details, which intersected with the longitudinal stiffener, found different degrees of fatigue cracking in the bridge examples in various countries. This paper, taking the Haihe Bridge in Tianjin as the engineering background, combined the bridge detection report, field test and finite element analysis to study the fatigue performance of the orthotropic steel bridge deck, estimated the structural details fatigue life, and the main fatigue life of the bridge. The contents include:
(1) on-site detection and record of the stress response of the cross beam of Haihe River Bridge during the process of vehicle passing, and simultaneous recording of vehicles and statistics, and simplified vehicle load spectrum.
(2) the section model of the steel box girder of Haihe Bridge is established by ABAQUS finite element analysis software, and the stress course of the measuring point of the diaphragm is calculated under the action of simplified vehicle load spectrum, and the load spectrum of the vehicle is checked by the comparison of the rain flow method and the measured stress history.
(3) to calculate the stress-strain history of the Haihe Bridge (with strut and non pole) by using the load spectrum of the checked vehicle, to estimate the fatigue life of the bridge, and to compare the structural details fatigue performance of the Haihe Bridge before and after the bracing.
(4) the initial residual stress is introduced into the horizontal plate model, and the strain history of the diaphragm is calculated, and the fatigue life of the hole position is reestimated by considering the correction of the average stress.
(5) study the change of the main stress state under the load of the vehicle, analyze the direction of the main tensile stress and compare with the actual cracking direction, and analyze the correlation between the trend of the change trend of the amplitude of the main stress and the change trend of the internal force of the diaphragm.

【学位授予单位】：天津大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U448.36;U441

【参考文献】