双主梁斜拉桥横隔梁受力分析及计算方法研究

发布时间：2018-02-27 09:22

本文关键词： 双主梁斜拉桥横隔梁成桥状态施工阶段简化模型受力分析　出处：《哈尔滨工业大学》2015年硕士论文　论文类型：学位论文

【摘要】：混凝土双主梁斜拉桥是目前桥梁工程中越来越普遍采用的一种结构形式,其主梁截面由两边主梁和桥面板组成,桥面宽度较大,两边主梁的横向联系相对较弱。双主梁斜拉桥的横隔梁是保证主梁横向刚度的重要构件,其可靠与否是整座桥梁安全运营的重要保障,因此横隔梁的设计成为双主梁斜拉桥设计中的重要一环。对于横隔梁的设计,绝大多数工程师为了计算方便而采用简化的杆系模型,从而导致横隔梁内力计算误差较大。本文以辽宁省朝阳市珠江桥为工程背景,讨论了横隔梁的作用,从成桥状态和施工阶段详细分析了各荷载作用下横隔梁的受力特点,并提出了修正的横隔梁简化计算模型,同时对比了不同预应力筋张拉方案对横隔梁受力均匀性的影响。首先,本文利用Midas/Fea建立了全桥实体模型,通过对比有、无横隔梁两种情况,从成桥整体受力、桥面板受力和主梁抗扭性能三个方面探讨了横隔梁在双主梁斜拉桥中的作用。分析结果表明,横隔梁能够提高主梁截面的横向刚度,减小边主梁与桥面板的相对变形,大幅度减小桥面板的横向应力,同时能够增强主梁在偏载作用下的抗扭性能。其次,本文通过对比目前横隔梁的三种简化计算方法与准确模型各荷载作用下的应力差值,对各简化模型进行了评价,得出简化模型准确度由高到低排序依次为节段实体模型法、简支梁法、固结梁法。基于模型分析,通过修正杆系模型的计算截面和边界条件,提出了满足工程精度的修正横隔梁简化模型。最后,本文建立了Midas/Fea施工阶段实体模型,分析了悬臂施工过程中自重、预应力、索力作用下横隔梁的应力变化规律。结果表明,随着离新浇筑横隔梁距离的增加,各荷载对已浇筑横隔梁产生的附加应力逐渐减小,其中自重的影响范围在6道横隔梁左右,预应力的影响范围在3道横隔梁左右,索力对已浇筑横隔梁的附加应力可忽略不计。针对珠江桥,对比了横隔梁预应力筋三种张拉方案对横隔梁受力的影响,得出一次落架状态横隔梁受力最均匀,预应力筋一次张拉和分批张拉两种方案下横隔梁受力均匀无显著差异。
[Abstract]:Concrete double girder cable-stayed bridge is a structure form of the bridge engineering more and more widely used, the main girder is composed of both girder and bridge deck, bridge deck width is large, horizontal contact on both sides of the main girder is relatively weak. Double girder cable-stayed bridge is an important component of cross beam to ensure the lateral stiffness of the main girder. Reliability is an important guarantee for the safe operation of the bridge, so the cross beam design into the design of double girder cable-stayed bridge is an important part of the design. The cross beam, the vast majority of engineers in order to facilitate the calculation by using the simplified model of bar system, resulting in cross beam internal force calculation error in this paper. In Liaoning Province, Chaoyang City Pearl River Bridge as the engineering background, discusses the effect of cross beam, from the finished bridge state and the construction stage are analyzed. The loading force of diaphragm beam characteristics, and brings forward the modified diaphragm beam. The calculation model, and effects of different tensioning schemes on the transverse beam uniformity were compared. First, Midas/Fea established a solid model of the whole bridge in this paper, by contrast, no cross beam two, from the bridge into the overall stress, discusses the cross beam in double girder cable-stayed the bridge in three aspects of torsion force and girder bridge deck. The analysis results show that the cross beam can improve the lateral stiffness of the main girder, the relative deformation decreases beam and bridge deck, transverse stress greatly reduce the bridge panel, at the same time can enhance the girder torsional performance in partial load next. Secondly, through the comparison of the three kinds of simplified cross beam calculation method and accurate model of the load stress difference, the simplified model was evaluated, the simplified model accuracy from high to low rank as model segment Method, beam method, consolidation beam method. Based on the analysis of the model, by modifying the bar calculation section and the boundary condition model, put forward to meet the engineering precision correction cross beam model. Finally, this paper established the entity Midas/Fea construction stage model, analyzes the cantilever construction process of prestressed cable, weight, force transverse stress variation of beam. The results show that with the increase of distance from the new pouring of cross beam, the cross beam has been pouring load on the additional stress decreases gradually, which affect the range of weight in the 6 way cross beam, influence range of pre stress in the 3 way cross beam about cable force of diaphragm beam has been pouring additional stress can be neglected. In view of the Pearl River Bridge, influence of cross beam prestressed reinforcement tension scheme of three cross beams were compared, obtained a falling state of cross beams is the most uniform, pre stress reinforced a piece Pull and batch tension under the two kinds of schemes of cross beams with uniform no significant difference.

【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U441;U448.27

【引证文献】