简支变连续预加配载法加固旧桥的分析研究

发布时间：2018-09-17 12:12

【摘要】：摘要：鉴于我国现有桥梁引桥多采用装配式简支T梁的结构形式,桥梁在长期的使用过程中,存在不同程度的损伤、结构老化；桥梁所承受的荷载等级有不断加大的趋势；时常有大型车辆通过桥梁,短期的过载会给桥梁造成永久的损伤,故有桥梁已经不能满足现在交通的需求,因此对故有桥梁的加固改造越来越迫切。本文以“九江长江大桥引桥(4×40)m连续梁”为工程背景,借助于大型有限元分析软件Midas/Civil,探讨了简支T梁利用预加配载法简支变连续加固后结构的受力性能。本文主要工作如下： 1.建立该桥加固前后的有限元分析梁格模型,分析加固前后成桥阶段结构的内力变化特点。 2.计算原结构和改造后结构在不同配载下内力、应力的变化规律,并对实际工程提出合理的影响参数建议。 3.分析对比了桥梁采取双排支座和单排支座时结构的中跨和边跨跨中内力以及反弯段应力、裂缝的变化规律,并建议给出了在同等配筋下结构支座的采用形式以及预加配载荷载的大小。 4.通过对预加配载法和预应力法简支变连续法结构墩顶反弯段应力的对比分析,得出简支桥梁使用预加配载法加固旧桥应用于工程实际是可行的。
[Abstract]:Absrtact: in view of the fact that the existing bridge approach bridges in our country mostly adopt the prefabricated simply supported T-beam structure form, the bridge in the long-term service process, there are different degrees of damage, aging of the structure, the load level of the bridge has a trend of increasing. There are often large vehicles passing through the bridge, the short-term overload will cause permanent damage to the bridge, so the bridge can no longer meet the needs of the current traffic, so it is more and more urgent to strengthen the bridge. Taking the (4 脳 40) m continuous beam of the approach bridge of Jiujiang Yangtze River Bridge as the engineering background, this paper discusses the mechanical behavior of the simply supported T-beam strengthened by the preloading method with the help of the finite element analysis software Midas/Civil,. The main work of this paper is as follows: 1. The finite element analysis model of the bridge before and after strengthening is established, and the variation characteristics of the internal force of the structure in the stage of the bridge before and after reinforcement are analyzed. 2. The variation law of internal force and stress of the original structure and the reconstructed structure under different loading is calculated, and the reasonable influence parameters of the actual engineering are suggested. 3. This paper analyzes and compares the internal force of middle span and side span of bridge with double row support and single row support, as well as the variation law of stress and crack in reverse bending section. It is also suggested that the structure bearing under the same reinforcement should be adopted and the size of preloaded load. 4. 4. Based on the comparative analysis of the stress in the reverse bending section of the piers by the preloading method and the prestressed method, it is concluded that it is feasible to use the preloading method to reinforce the old bridge in engineering practice.
【学位授予单位】：中南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U445.72

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