黄梅沙河桥设计
摘 要
本设计是根据设计任务书的要求和《公路桥规》的规定,对黄梅县大桥进行方案比选和设计的。本着“安全、经济、美观、实用”的原则，本论文提出三种不同的桥型方案进行比较和选择：方案一为预应力混凝土等截面简支T梁桥，方案二为预应力混凝土变截面连续箱梁桥，方案三为钢筋混凝土下承式钢管拱桥。根据以上的原则以及设计施工等多方面考虑，比较确定预应力混凝土等截面简支T梁桥为推荐方案，绘制三种方案的桥址平面图、立面图、横断面图。
在设计中，桥梁上部结构运用Madis/Civil软件建模分析，进行主梁的截面几何特性计算、荷载横向分布计算，以及恒载及活载布载的内力计算。运用铰接梁法求出活载横向分布系数，并运用最大荷载法进行活载的加载。进行了梁的配筋计算，估算了钢绞线的各种预应力损失，绘制预应力筋布置图。对结构强度、刚度、应力、裂缝宽度、挠度等进行验算。由于时间关系，本设计没有进行下部结构的设计。
关键词： 方案； 简支T梁桥； 比选； MADIS； 验算
I
The Design of the huangmei shahe Bridge
Abstract
The design was to compare the schemes and to design for the Huangmei county bridge based on the requirements of the design task and \. The design of the bridge presents three different kinds of bridge model plans to compare and choose in line with the principle of ―safety, economically, aesthetic and practically‖ : The first program was the design of the section simple supported T-beam of prestressed concrete, the second one was prestressed concrete variable cross-section continous grider bridge, the third one was reinforced concrete steel-tabular arch bridge. According to the principle as well as design and construction aspects, the prestressed concrete simply supported T-beam bridge of the section was regarded as recommended scheme. Drawing the preliminary plan ,elevation cross section drawing of the three schemes.
In the design, the upper structure of bridge used Madis/Civil software to model and analyze, and to make the geometry specialty of the main grider cross-section calculation, the load transverse distribution coefficient calculation, and dead load &live load internal force calculation. The hinged beam method for calculating coefficients of transverse distribution, and applying the maximum load method to have live-load loading. Making the beam reinforcement calculation, calculating the various loss of prestress of steel strand, drawing prestressed tendon layout .checking the structural strength, stiffness, stress, crack width and deflection. In the interest of time , the bottom structure design was not involved in this design.
Key words: Scheme; Simple Supported T-beam; Comparison;
MADIS; Checking
II
目 录
中文摘要 ......................................................... I 英文摘要 ......................................................... II 1 绪论 ......................................... 错误！未定义书签。
1.1 预应力混凝土简支T梁桥概述 .......... 错误！未定义书签。
1.1.1 预应力混凝土特点 ..................................... 1 1.1.2 简支梁桥特点 .......................................... 1 1.1.3 T梁桥特点 ............................................. 2
1.2 国内发展研究状况 ....................................... 2 1.3 研究的方法和内容 ....................................... 3
2 方案比选 ..................................................... 4
2.1 工程概况 ................................................. 4
2.1.1 主要技术指标 ......................... 错误！未定义书签。 2.1.2 现场工程地质条件 .................... 错误！未定义书签。
2.2 桥梁设计原则 ............................................ 5 2.3 方案编制 ................................ 错误！未定义书签。 2.4 方案比选 ................................................ 10
3 MIDAS建模分析 ............................. 错误！未定义书签。
3.1 计算横向分布系数 ...................... 错误！未定义书签。 3.2 建立模型 ................................ 错误！未定义书签。
4 内力计算与荷载组合 ....................................... 16
4.1 恒载内力的计算 ......................................... 16
4.1.1 恒载内力 ............................................. 16
III
4.1.2 恒荷载组合 ........................................... 17
4.2 活载内力计算 ........................... 错误！未定义书签。
4.2.1 车道荷载引起的内力 .................................. 20 4.2.2 活载组合 ............................................. 21
5 配筋设计和截面验算 ....................................... 30
5.1 预应力钢束 ............................................. 30
5.1.1 预应力钢筋截面积估算 ............................... 30
5.2 预应力钢束布置 ......................................... 31
5.2.1 布置要求 ............................................. 31 5.2.2 钢束特性 ............................................. 32 5.2.3 布置预应力钢束 ...................................... 32
5.3 普通钢筋 ............................................... 303
5.3.1 普通钢筋截面积估算 .................................. 33 5.3.2 普通钢筋的布置 ...................................... 34
5.4 截面验算 ............................................... 35
5.4.1 受拉区钢筋拉应力验算 ............................... 35 5.4.2 使用阶段正截面压应力验算 ........................... 36 5.4.3 正截面抗弯承载力验算 ............................... 37 5.4.4 使用阶段斜截面抗剪验算 ............................. 38 5.4.5 使用阶段斜截面主压应力验算 ......................... 40 5.4.6 使用阶段正截面和斜截面抗裂验算 .................... 41
结 论 ........................................................... 45 参考文献 ........................................................ 46 致 谢 ........................................................... 47
IV
附录1 外文参考文献（译文） .............................. 48 附录2 外文参考文献（原文） .............................. 62
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