摘 要

近几十年以来，随着我国科学技术水平的不断发展提高，与桥梁相关的建筑工艺和技术水平也得到了飞速的发展。作为未来的桥梁工作者，我们必须全面地、系统地掌握整个桥梁的设计全过程。本次设计根据所给设计资料，对桥梁的设计进行了研究，大致包含以下几个方面的内容：

1. 参考国内外大跨径拱桥修建的现状及发展趋势，结合杨家河大桥具体的方案选择原则和技术标准，对此桥提出三个可供选择的方案：预应力混凝土连续刚构桥，单孔上承式拱桥，斜拉桥。通过方案比选后，本设计采用单孔上承式拱桥。
2. 根据构造要求及经验对该桥进行截面设计及尺寸拟定：主拱截面采取箱型拱。

（3）采用软件Midas Civil对该桥梁进行恒载、活载内力计算。恒载内力计算需分一期恒载，二期恒载。活载内力计算包括车辆荷载和人群荷载。

（4）要根据计算的荷载在结构上所产生的作用效果及结构所承受的荷载强度对梁截面强度进行验算。如不符合要求则应对截面尺寸和钢筋的布置进行调整直到合格。

通过数据的分析和比较以及桥梁强度的验算表明该桥梁设计的计算方法正确，并且内力的分布符合规律，同时可以满足设计任务的全部要求。

关键词：单孔上承式拱桥；箱型拱；Midas Civil；结构设计计算；

Abstract

In recent decades, with the continuous development and improvement of science and technology in China, the construction technology and technology level related to bridges have also been developed rapidly. As a bridge worker in the future, we must master the whole process of bridge design comprehensively and systematically. According to the given design data, the design of the bridge has been studied, which roughly includes the following aspects：

1. Referring to the current situation and development trend of long-span bridge construction at home and abroad, combined with the specific scheme selection principles and technical standards of yangjiahe bridge, three alternative schemes are proposed for this bridge: prestressed concrete continuous rigid frame bridge, single hole through arch bridge and cable-stayed bridge. After the scheme comparison, the single hole through arch bridge is adopted in this design.
2. According to the structural requirements and experience of the bridge section design and size proposed: the main arch section adopts box arch.
3. The software MIDAS civil is used to calculate the dead load and live load internal force of the bridge. The calculation of dead load internal force needs to be divided into one stage of dead load and two stages of dead load. The internal force calculation of live load includes vehicle load and crowd load.
4. The reinforcement of the bridge is calculated by the control internal force of each section. According to the bending moment of bearing section and midspan section, the prestressed reinforcement is calculated and arranged according to the requirements of normal section strength when the bearing capacity limit state is met.
5. The strength of beam section should be checked according to the effect of calculated load on the structure and the load strength of the structure. If it does not meet the requirements, the section size and reinforcement arrangement shall be adjusted until it is qualified.

The analysis and comparison of the data and the checking calculation of the bridge strength show that the calculation method of the bridge design is correct, and the distribution of the internal force conforms to the law, and can meet all the requirements of the design task at the same time.

Keywords: single hole through arch bridge; box arch; Midas civil; structural design and calculation;

目 录

第1章 绪论 1

第2章 方案比选 2

2.1 设计资料与技术标准 2

2.1.1 设计标准 2

2.1.2 设计规范 2

2.1.3 设计书以及标准图 2

2.1.4 设计基本资料 2

2.2 桥型方案构思的基本思想 7

2.3 方案设计 8

2.3.1 概论 8

2.3.2 桥梁设计原则 8

2.3.3 结构形式 10

第3章 尺寸拟定与设计 15

3.1 总体布置 14

3.2 上部主体构造 14

3.2.1 桥面横向布置 14

3.2.2 箱梁尺寸拟定 15

3.2.3 桥面构造 16

3.3 下部主体构造 16

第4章 结构计算 18

4.1 创建模型 18

4.1.1 定义结构材料 18

4.1.2 建立节点和单元 18

4.1.3 定义截面和变截面 18

4.1.4 定义变截面组 18

4.1.5 输出模型 18

4.2内力计算 19

4.2.1 恒载内力计算 19

4.2.2 活载内力计算 32

4.2.3 使用阶段荷载组合 58

第5章 桥面板布置 73

5.1跨中截面正截面抗弯承载力验算 73

第6章 施工组织设计 75

6.1 材料质量检验 75

6.2 桥梁基础施工 75

6.4 桥面系施工 76

6.4.1 铺装层施工 76

6.4.2 伸缩缝施工 77

第7章 设计感谢与收获 78

参考文献 79

致谢 80

第1章 绪论

中国自古以来就是桥梁大国，由于我国地大物博，各种地方存在的差异较大，也行成了各种各样的桥梁形式。

其中拱桥具有跨越能力较大；可以就地取材，与钢筋混凝土桥相比，可以节省大量的钢材和水泥；能耐久，而且养护、维修费用少；构造较简单，尤其是圬工拱桥，技术较容易被掌握，相对于其他桥种来说更加美观，有利于广泛采用等优点，在大部分地区有着广阔的运用。

本文结合杨家河大桥具体的方案选择原则和技术标准，对此处山区桥展开设计，基本确定该桥跨度为180m，通过对方案进行比选后，本设计采用上承式拱桥设计。

第2章 方案比选

2.1 设计资料与技术标准

一、设计标准

1.计算行车速度：80km/h;