目录第一章1.1 选题背景.................................................... - 3 -1.2 工程概况................................................... - 3 -1.2.1 概况.................................................. - 3 -1.2.2 自然条件情况.......................................... - 3 -1.3 技术指标和技术依据.......................................... - 4 -1.3.1 技术指标.............................................. - 4 -1.3.2 技术依据............................................... - 4 -本设计主要依据为现行技术规范和标准：......................... - 4 -1.4 结构形式.................................................... - 4 -1.5主要材料..................................................... - 5 - 第 2 章上部结构设计................................................ - 6 -2.1设计资料..................................................... - 7 -2.2构造形式及尺寸选定........................................... - 7 -2.3空心板毛截面几何特性计算..................................... - 7 -2.3.1 毛截面面积A ........................................... - 7 -2.3.2 毛截面重心位置......................................... - 9 -2.3.3 空心板毛截面对其重心轴的惯性矩I....................... - 9 -2.4作用效应计算................................................ - 10 -2.4.1 永久作用效应计算...................................... - 10 -2.4.2 可变作用效应计算........................... 错误!未定义书签。

2.5 作用效应组合............................................... - 12 -2.6 预应力钢束的估算及布置..................................... - 23 -2.6.1 预应力钢筋数量的估算.................................. - 23 -2.6.2 预应力钢筋的布置...................................... - 23 -2.7 普通钢筋数量的估算及布置................................... - 26 -2.8 主梁几何特性计算........................................... - 26 -............................ - 30 -2.9.1 预应力钢筋张拉控制应力con2.9.2 钢束应力损失......................................... - 30 -2.10 承载能力（强度）极限状态的验算........................... - 30 -2.10.1 跨中截面正截面抗剪承载力计算........................ - 36 -2.10.2 斜截面抗剪承载力计算..................... 错误!未定义书签。

2.10.3 斜截面抗弯承载力.................................... - 36 -2.11 正常使用极限状态验算..................................... - 40 -2.11.1 抗裂性验算........................................... - 40 -2.12 主梁变形验算............................................. - 41 -2.12.1 荷载短期效应作用下主梁挠度验算...................... - 44 -2.12.3 预拱度的设置............................. 错误!未定义书签。

2.13 持久状况应力验算......................................... - 44 -2.13.1 短暂状况的正应力验算................................ - 45 -2.13.2 持久状况的正应力验算................................ - 45 -2.13.3 持久状况下混凝土主应力验算............... 错误!未定义书签。

2.14 锚固区局部承压计算....................................... - 46 -2.14.1 局部承压尺寸要求.................................... - 48 -2.14.2 局部抗压承载力计算.................................. - 48 - 第 3 章下部结构设计.............................................. - 51 -3.1钻孔桩计算.................................................. - 51 -3.1.1 荷载计算.............................................. - 52 -3.1.2 桩长计算.............................................. - 52 -3.1.3 桩的内力计算（m法）.................................. - 56 -3.1.4 桩身截面配筋与承载力验算（图3-4）.................... - 58 -3.1.5 墩顶纵向水平位移验算.................................. - 58 - 参考文献........................................................... - 63 - 致谢........................................................... - 64 -摘要按照三湾河桥设计任务书的要求，提出两个设计方案：方案一为预应力混凝土箱形简支梁桥，方案二为预应力混凝土T形简支梁桥，本着“安全、经济、实用、美观”的原则，最后确定预应力混凝土箱形简支梁桥为推荐方案。

将所推荐桥梁进行了全面的计算分析，利用横向分布系数确定活载分布，求得上部结构主梁的内力，从而确定主梁配筋，然后进行主梁强度和应力验算，并分析验算了横梁和桥面板。

对下部结构桥墩、桥台和基础作了详细的内力计算与验算。

同时，根据计算结果绘制了桥梁全套的施工图。

关键词：预应力混凝土简支梁桥；配筋；强度；应力AbstractAccording to designing assignment of San-wan river, two projects are provided. One is prestressed concrete simply supported box beam bridge. The other is prestressed concrete simply supported T beam bridge. In line with the rule of “safe, economical, practical and artist ic”, the prestressed concrete simply supported box beam bridge is suggested finally.The suggested bridge is calculated and analyzed fully. Live load is determined with traverse coefficient. Beam force of up structure is got and prestressed steel bar is confirmed. Beam strength and stress checking calculations are proceeded. Traverse beam and surface plate are analyzed and checking calculated. Piers, bents and foundations of low structure are calculated for force and analyzed. In the same time, full construction drawings are drawn according to the calculation result.Key words: Prestressed concrete simply supported beam bridge；steel bar deployment；strength；stress第1章 绪论1.1 设计背景桥梁作为跨越江河、山谷及其它线路（公路、铁路）等障碍物的重要结构物，也得到了相应发展，由此，我国的桥梁建设水平也迈进了世界先进行列。