论文总字数：50419字

2019 届毕业设计（论文）

题 目： 江苏宝射河大桥

预应力混凝土连续梁桥设计

专 业： 土木工程

班 级： 土木 1507

姓 名： 吴桐

指导老师： 张南

起讫日期： 2019.2-2019.6

1. 年 6 月

iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii

Design of Prestressed Concrete Continuous Girder Bridge of Baoshehe Bridge in Jiangsu Province

abstract

This design is based on the requirements of the design task sheet and the provisions of Highway Bridge Regulation to optimize the design of Shaohai North Road, Jiaozhou City.Main Bridge Scheme of Bridge No. Firstly, according to the general situation of the project and the requirements of the specifications, the scheme design and comparison of the bridge are carried out. The selected scheme is a three-span prestressed concrete continuous beam bridge with variable span. The box section with single box and single chamber and variable height is adopted. The web is straight web, and the construction method is cantilever casting. After preliminarily drawing up the layout of bridge span and section size according to highway bridge rules and design manual, the bridge model is established by Midas software and the loads of dead load, live load and secondary internal force of the structure are calculated. Then the load combination and envelope diagram are drawn. Then the estimation and arrangement of prestressing steel bar, geometric characteristics of section and prestressing loss are calculated manually; and then the upper structure is checked by hand calculation. The results meet the design requirements. Finally, the preliminary design of the lower structure is carried out, using basin rubber bearing, double-column pier and pile foundation. In addition, the design has also carried out the amount of budget, construction drawings and other work.

Key words:Design; Continuous girder bridge; Prestress; Cantilever construction

方案设计

跨径布置

1.1.1 标准跨径

江苏宝射河大桥,桥梁全宽26米，主桥长152米。本桥的设计采用的是变截面连续箱梁结构形式，为了在总体上保证桥的美观性及整体协调，在跨径布置时，要和前面以及后面联协调好，再通过计算进行调整，最后确定本桥的跨径布置如下：

42 68 42=152米

标准跨径（相邻墩身轴线的距离）布置如图1.1所示

图 1-1 标准跨径布置(单位：m)

通过上面的图可以知道本桥为三跨连续梁桥，有利于对称悬臂施工。根据参考文献[1](P227)，悬臂施工变高度的连续梁桥一般的边中跨比为 0.5~0.65，且应该对称来布置。本桥中选择的边跨与中间跨之比为 0.618:1

1.1.2 计算跨径

上面跨径的布置是标准跨径，计算跨径的时候还应该考虑到两个边跨伸缩缝的长度以及支座尺寸的折减损耗。

为了减小伸缩缝的宽度，把固定支座放在 2#墩上，让梁体向两边伸缩。由设计任务书可知

该桥的设计年平均温差为±20℃，混凝土材料的温度膨胀系数为 ，左右两边各预期留的伸缩缝宽度为：3cm，3cm；然后考虑到支座的尺寸影响，计算的跨径布置如下图 1-2：

0.47 41.5 68 41.5 0.47

图 1-2 计算跨径布置(单位：m)

由上图可知连续梁两端分别有 0.47m 和 0.47m 的悬臂段，但由于其长度很小，并且因为位于支座的上面，对于内力的影响比较小，所以在内力的计算中可以忽略。所以计算跨径为：

请支付后下载全文，论文总字数：50419字