摘 要

近年来，随着我国交通事业的快速发展，预应力混凝土连续刚构桥在桥梁设计中的应用越来越广泛。相较于其他桥梁，连续刚构桥有许多显著的优势。例如跨越能力大，施工方便，行车舒适，造价较低等。基于以上优势，连续刚构桥在我国新建桥梁中占据着相当大的比例。

本文总结了连续刚构桥近年来的国内外发展趋势及现状，并介绍了连续刚构桥的一般特点和施工方法。基于以上方面的调查研究，本文对西藏雅江大桥进行了设计和计算。本文通过Midas/Civil这款软件建立桥梁模型并模拟施工过程，完成在各种极限状态下桥梁的内力的验算，并对施工过程中桥梁的受力情况进行分析。最后，本文对桥梁的施工过程和要点进行了设计和介绍。

本文对于西藏雅江大桥的设计及计算，不仅解决了实际工程问题，也进一步积累了连续刚构桥设计经验。目前，各种桥梁仿真设计软件和结构分析软件不断发展，各类高强材料轻型混凝土也开始普遍应用，连续刚构桥的施工工艺和方法也在不断进步和成熟。可以预见，在不远的将来，连续刚构桥将成为桥梁建设中的主要趋势。

关键词： 连续刚构桥；模型；结构计算。

Abstract

Recently, with the rapid development of the highway transportation in our country, the prestressed concrete continuous rigid frame bridge is adopted more and more extensively. Compared with other kind of bridges, the continuous rigid frame bridge has many significant advantages. For example, the continuous rigid frame bridge has great spanning capacity, convenient construction, vehicle body and low cost. Based on such advantages, the continuous rigid frame bridge has occupied the considerable proportion of new-built bridge in our country.

This paper made a summary about the recent situation and trend of the continuous rigid frame bridge around the world. It also introduced the general characteristics and the method of the construction of the continuous rigid frame bridge. Based on the investigation of the above aspects，this paper made the design and calculation of Yajiang Tibet Bridge. Through the function of Midas/Civil, this paper has built the model of the bridge and simulated construction process. It has finished the calculation of internal force of bridge under various limit states and the analysis of the stress of the bridge in the construction process. Finally, this paper has designed and introduced the construction process and main points of the bridge.

The design and calculation of Yajiang Tibet bridge in this paper, not only solved the practical engineering, but also further accumulated the design experience of continuous rigid frame bridge. At present, with the development of the software of simulation design and structural analysis in the field of bridge engineering, wide application of various types of high-strength materials and lightweight concrete, continuous progress and mature of technology and method of rigid frame bridge construction , it can be predicted that continuous rigid frame bridge will become the main trend in bridge engineering in the near future.

Keyword: Continuous rigid frame bridge；Model；Structure calculation.

目录

第一章 绪论 1

1.1连续刚构桥概述 1

1.2国内外发展现状 1

1.2.1国外发展历程 1

1.2.2国内发展历程 2

1.3连续刚构桥特点 2

1.4施工技术 4

1.5发展趋势 5

1.6本文研究的内容 6

第二章 设计基本情况说明 7

2.1设计依据 7

2.2技术标准 8

2.3主要材料 8

2.4设计规范 8

2.5设计内容及注意事项 9

第三章 桥型方案设计 10

3.1方案比选的意义及要求 10

3.2初选方案 10

3.3方案分析 10

3.4综合比较 11

3.5连续刚构桥详细设计方案 20

3.5.1总体设计 20

3.5.2上部构造 20

3.5.3下部结构 22

3.6连续刚构桥施工方案 22

3.6.1施工过程 22

3.6.2施工流程图 23

第四章 有限元模型的建立 24

4.1建立模型 24

4.1.1材料和截面 24

4.1.2节点和单元 24

4.1.3边界条件和约束 24

4.1.4静力荷载工况 26

4.1.5输入预应力钢筋 26

4.2定义组 26

4.3定义施工阶段 28

4.4运行计算 33

第五章 桥梁上部结构计算 34

5.1承载能力极限状态 34

5.2施工阶段正应力验算 36

5.3正常使用极限状态 38

5.3.1正截面抗裂验算 38

5.3.2正截面抗压验算 41

5.3.3主应力验算 44

第六章 总结 48

参考文献 49

附录 51

致谢 52

第一章 绪论

1.1连续刚构桥概述

连续刚构桥是墩梁固结的连续桥梁，是在连续梁桥基础上发展起来的新型桥梁。连续刚构桥其实是T构桥梁的一类。而T构大致分为三种基本类型，一种是单个T构形成的悬臂梁；另一类是带铰或挂孔的主梁不连续的T构；还有一类是主梁连续的T构，即连续刚构。大跨连续刚构一般采用双薄壁高墩和箱形截面。由于其本身结构力学特性的优势和大量高强材料的使用，连续刚构桥具备较大的横向抗扭刚度和顺桥向的抗弯刚度，变形较小，跨越能力较强，并且具有良好的抗震性能。连续刚构的上部结构有连续梁的受力特点，但在墩梁固结处，仍有刚架的受力特点。较连续梁桥而言，连续刚构墩顶负弯矩较小，跨中的正弯矩也大大削减。对于跨径在200m～300m范围内的桥梁，连续刚构桥有着其他桥型无可比拟的优势，连续梁桥在跨越方面、拱桥在施工方面、斜拉桥及悬索桥在经济指标方面均无法与连续刚构桥竞争。

1.2国内外发展现状