混合连续梁桥接头部位受力研究

发布时间：2018-05-20 02:28

本文选题：混合桥 + 组合梁　；参考：《吉林建筑大学》2014年硕士论文

【摘要】：近年来，随着大跨径桥梁不断的发展，钢—混凝土混合结构被很多大跨径桥梁所采用。这种混合结构充分发挥了混凝土与钢的优势，这种结构整体性好，，刚度大，承载能力强，动力性能好，自重小，而且施工比其他结构方便，使得桥梁性能上得到大幅提高。在钢-混凝土混合梁桥中，钢箱梁与混凝土梁通过接头进行连接，由于钢与混凝土是刚度与强度不同的两种材料，所以接头部位在受力作用下，接头的外形尺寸发生突变容易引起接头结构局部的内力增大。钢-混凝土接头是混合结构中的薄弱之处。本文以重庆长江大桥复线桥为背景工程，该桥梁2006年9月24日竣工通车。该桥采用预应力混凝土连续梁桥和连续刚构桥组合形式，桥跨布置为87.75+2×138（预应力混凝土连续梁桥结构）+2×138+330（钢箱梁主跨）+132.5（连续钢构结构）。主跨由左右两侧111m预应力混凝土悬臂和中间108m钢箱梁形成钢混组合式结构。该桥主跨达330m，打破此类桥梁的最大跨径的世界纪录，该桥为了避免由于预应力连续刚构自重产生的过大的应力而难以提高跨越能力的问题，在主跨330m中采用108m钢箱梁，这样有效的解决了预应力混凝土连续刚构自重过大影响跨越能力的问题。组合梁充分发挥了混凝土与钢梁受力时各自的优点，因此组合梁具有承载力高的优点，同时组合梁还具有自重小，减弱地震作用，施工方便，结构延性好等其他一些优点。组合梁这种结构被广泛的应用到结构设计中。鉴于组合梁的这些特点，本文在重庆长江大桥复线桥的原桥基础上拟定新的混合结构形式：将原桥330m主跨中的108m钢箱梁用组合梁替换，然后对结合段处的接头进行动力分析，分析混凝土—组合梁接头受力情况。本文工作内容主要有：（1）收集、整理有关文献总结混合结构和接头的有关理论和研究现状。（2）利用MIDAS CIVIL建立原桥模型和新的组合-混凝土混合梁有限元模型。分别计算出两种模型接头处在地震作用下的最不利荷载组合。（3）利用有限元软件ANSYS建立钢-混凝土接头与组合-混凝土接头有限元模型，进行静力分析。（4）得出接头各个构件应力计算结果，进行详细的对比分析，初步得出混合梁接头在地震作用下的应力范围和应力分布规律，提出意见。
[Abstract]:In recent years , with the continuous development of large - span bridges , the hybrid structure of steel - concrete has been adopted by many large - span bridges . This hybrid structure gives full play to the advantages of concrete and steel , and the structure is good in integrity , large in rigidity , strong in bearing capacity , good in power performance , small in dead weight , and convenient in construction than other structures , so that the bridge performance is greatly improved .

in that steel - concrete composite beam bridge , the steel box beam and the concrete beam are connected through a joint , because the steel and the concrete are two materials with different rigidity and strength , the external dimension of the joint can easily cause the local internal force of the joint structure to increase under the action of stress , and the steel - concrete joint is weak in the mixed structure .

This paper takes Chongqing Yangtze River Bridge as background project . The bridge is completed on September 24 , 2006 . The bridge is composed of prestressed concrete continuous beam bridge and continuous rigid frame bridge . The bridge span is 87.75 + 2 脳 138 ( prestressed concrete continuous beam bridge structure ) + 2 脳 138 + 330 ( steel box girder main span ) + 132.5 ( continuous steel structure ) .

The composite beam has the advantages of high bearing capacity , and the combined beam has the advantages of small dead weight , reduced earthquake action , convenient construction , good structural ductility , etc . The composite beam has many advantages such as small dead weight , reduced earthquake action , convenient construction and good structural ductility .

The main contents of this paper are as follows :

( 1 ) Collect and arrange relevant literatures to summarize the relevant theories and research status of hybrid structures and joints .

( 2 ) The finite element model of the original bridge model and the new composite - concrete composite beam is established by using MIDAS truss . The most unfavorable load combinations of two model joints under earthquake are calculated .

( 3 ) The finite element model of steel - concrete joint and composite - concrete joint is established by finite element software ANSYS , and static analysis is carried out .

( 4 ) obtaining the stress calculation results of each component of the joint , carrying out detailed comparative analysis , and preliminarily obtaining the stress range and the stress distribution rule of the mixed beam joint under the earthquake action , and putting forward opinions .
【学位授予单位】：吉林建筑大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U441

【参考文献】