简支转连续T梁

摘要

榕树大桥位于福建省，是双永高速公路上的一座跨线桥，单幅宽12.25m，五跨等跨径为30m，全长150m。榕树大桥简支转连续T梁结构总体的设计，需要理解桥梁体系的转换，采用桥梁博士软件进建立模型。设计主要内容有：恒载和活载计算，估算配筋面积，配置预应力钢束；计算细部结构的受力状况；划分各个施工阶段，对每个施工阶段进行结构安全的受力计算和分析；使用阶段进行结构永久荷载、活荷载、预应力和附加应力的计算和结构合理性的分析；承载能力极限状态和正常使用极限状态的截面验算，作出包罗图；根据上部结构的计算结果对下部结构进行设计。设计难点有：预应力的张拉控制和施工阶段的加载。我在本设计中简化了施工，总共3施工阶段，计算方便。

关键词：简支转连续，预应力连续T型梁，桥梁博士，预应力钢束，施工阶段，恒载，活载，应力组合，包络图，截面验算。

Abstract

Banyan Bridge is located in Fujian Province, is a two-Yong highway overpass, a single width of 12.25m, total length of 150m. Banyan Bridge simply supported T beam continuous overall design, need to understand the conversion of the bridge system, the use of Bridge Doctor software into the model. Design elements include: dead load and live load calculations, estimates reinforcement size, configuration prestressed steel beam; calculate detailed structure of the stress state; by each construction stage, construction stage of the structural safety of each of the force calculation and analysis ; with stage structure, permanent loads, live loads, prestressed and additional stress calculations and structural analysis of reasonableness; ultimate limit state and limit state sectional checking; structure calculation based on the results of the upper structure of the lower part of the design. Design challenge are: pre-stress tension control and construction phase of the load. I simplified the design, construction, total construction phase 3, calculation is simple.

Key words: simply supported continuous prestressed T-beam Bridge Doctor, prestressed steel beams, construction stage, dead load, live load, stress combination,

envelope, cross checking.

目录

前言 ......................................................................................................................... - 1 -第一章工程概况 ............................................................................................... - 2 -

1.1 工况简介.................................................................................................... - 2 -

1.2 桥型布置.................................................................................................... - 2 -

1.3方案比选..................................................................................................... - 3 -

1.4结构尺寸..................................................................................................... - 4 -

1.4.1主梁间距及主梁片数...................................................................... - 4 -

1.4.2截面效率指标.................................................................................. - 5 -

1.5 预应力钢筋布置........................................................................................ - 6 -

1.6 桥面铺装及防水排水系统...................................................................... - 6 -

1.6.1桥面铺装.......................................................................................... - 6 -

1.6.2桥面纵横坡...................................................................................... - 6 -

1.6.3防水层.............................................................................................. - 7 -

1.6.4桥面排水系统.................................................................................. - 7 -第二章设计资料及主要技术标准............................................................... - 7 -

2.1 主要设计规范及设计参考资料................................................................ - 7 -

2.2 主要设计技术指标.................................................................................... - 7 -第三章设计荷载及主要材料 ................................................................... - 9 -

3. 1主要材料及特性........................................................................................ - 9 -

3. 1.1基本材料及特性见表：................................................................. - 9 -

3.1.2 施工工艺......................................................................................... - 9 -

3.2设计荷载..................................................................................................... - 9 -

3.2.1恒荷载计算.................................................................................... - 10 -

3.2.2横向分布系数计算........................................................................ - 11 -

3.3 活载内力计算.......................................................................................... - 15 -

3.4 桥面板的计算.......................................................................................... - 20 -

3.4.1 桥面板恒载内力计算................................................................... - 20 -

3.4.2 桥面板活载内力计算................................................................... - 21 -

3.4.3 内力组合及桥面板配筋............................................................. - 22 -第四章桥梁结构分析.................................................................................. - 23 -

4.1 结构离散化的基本原则.......................................................................... - 23 -

4.2计算模型和单元的划分........................................................................... - 24 -

4.3 结构毛截面几何特性计算...................................................................... - 24 -

4.4施工阶段的划分....................................................................................... - 26 -第五章主要结构计算分析及结论............................................................. - 28 -