三跨预应力连续箱梁桥设计论文.doc

三跨预应力连续箱梁桥设计毕业论文 目录 摘 要 1 0 绪论 3 1 设计基本资料 5 1.1.工程概况 5 1.2.设计标准 5 1.3.桥梁设计 5 2 设计要点及结构尺寸拟定 7 2.1设计要点 7 2.2结构尺寸的拟定 8 3 主梁作用效应的计算 11 3.1 自重作用效应的计算 11 3.2汽车荷载的效应 17 3.3温差应力的计算 26 3.4支座沉降的计算 28 3.5内力组合 28 4 预应力钢筋的估算与布置 36 4.1钢束的估算 36 4.2钢束的布置 37 4.3主梁净、换算截面几何特性计算 38 5 预应力损失及有效预应力计算 40 5.1 基本理论 40 5.2预应力损失计算 40 6 配束后主梁内力计算及内力组合 49 7 截面强度验算 52 7.1基本理论 52 7.2计算公式 52 8 抗裂验算 56 8.1《公预规》要求 56 8.2抗裂计算 56 9 持久状况构件的应力验算 65 9.1正截面混凝土压应力验算 65 9.2预应力筋拉应力验算 67 9.3混凝土主压应力验算 68 10 短暂状况构件的应力验算 75 10.1预加应力阶段的应力验算 75 10.2吊装应力验算 76 致谢 78 参考文献 79 外文文献翻译 80  摘要本设计是联连续梁桥，形式为，；施工方式是。关键词：设计 连续梁桥 预应力 Abstract The continuous beam bridge is a kind of bridge type used widely on the project. It not only has a reliable strength, stiffness and cracking, but also has a smooth journey comfortable, conservation work on the design and construction experience of the characteristics of maturity. Design a bridge must be laid across from the bridge-laying, the size of the development, steel beam layout and construction methods, but also give full consideration to the design parameters and environmental impact. This is a design for a three-span continuous bridge, whose cross-section is one-compartment, and no changing on the road direction, constructed by after a first simply-supported. The first design includes constant load, the live load and the calculation of the internal forces. On the basis of a load combination, we can draw moment and shear envelope map. Next, according to the short-term effect combination disposition prestressed reinforcement, and carries on the loss of prestress the computation. Finally, carries on the checking calculation to this continuous bridge, whether to satisfy the design requirements. Key Words: design; continuous bridge; after a first simply-supported; prestress  0 绪论 0.1 预应力混凝土连续梁桥概述 为了解决这些问题，预应力混凝土结构应运而生，所谓预应力混凝土结构，就是在结构承担荷载之前，预先对混凝土施加压力。这样就可以抵消外荷载作用下混凝土产生的拉应力。自从预应力结构产生之后，很多普通钢筋混凝土结构被预应力结构所代替。 预应力混凝土桥梁是在二战前后发展起来的，当时西欧很多国家在战后缺钢的情况下，为节省钢材，各国开始竞相采用预应力结构代替部分的钢结