midas连续梁桥设计专题 - 图文 联系客服

发布时间 : 星期一 文章midas连续梁桥设计专题 - 图文更新完毕开始阅读ec9462f8770bf78a652954b6

Bridging Your Innovation to Reality

midas Civil 钱江

2011/5/18

培训专题集

连续梁桥设计专题

midas Civil 2010 培训例题

连续梁桥设计专题 目 录

1 桥梁概况 .......................................................................................................................................................... - 1 - 1.1 主要设计指标 ............................................................................................................................................ - 1 - 1.2 相关计算参数 ............................................................................................................................................ - 1 - 1.3 相关设计依据 ............................................................................................................................................ - 1 - 1.4 一般构造及钢束布置 ................................................................................................................................ - 1 -

1.4.1 一般构造 ........................................................................................................................................ - 1 - 1.4.2 钢束布置 ........................................................................................................................................ - 2 - 1.5 施工过程 .................................................................................................................................................... - 4 - 2 建模分析 ........................................................................................................................................................... - 5 - 2.1 模型概述 .................................................................................................................................................... - 5 - 2.2 建模要点 .................................................................................................................................................... - 5 -

2.2.1 定义材料与截面 ............................................................................................................................ - 5 - 2.2.2 定义节点、单元及边界条件 ........................................................................................................ - 7 - 2.2.3 定义时间依存材料特性 ................................................................................................................ - 7 - 2.2.4 定义静力荷载工况 ........................................................................................................................ - 8 - 2.2.5 定义预应力荷载 ............................................................................................................................ - 9 - 2.2.6 定义移动荷载 .............................................................................................................................. - 10 - 2.2.7 定义支座沉降 .............................................................................................................................. - 11 - 2.2.8 定义施工阶段 .............................................................................................................................. - 12 - 2.2.9 定义结构质量 .............................................................................................................................. - 12 - 2.2.10 定义梁的有效宽度 .................................................................................................................... - 12 - 2.3 分析控制定义 .......................................................................................................................................... - 13 -

2.3.1 定义施工阶段分析控制 .............................................................................................................. - 13 - 2.3.2 定义移动荷载分析控制 .............................................................................................................. - 13 - 2.3.3 定义特征值分析控制 .................................................................................................................. - 14 - 2.3.4 定义主控数据 .............................................................................................................................. - 14 -

3 结合规范进行设计 ......................................................................................................................................... - 14 - 3.1 定义荷载组合 .......................................................................................................................................... - 14 - 3.2 定义PSC设计 ............................................................................................................................................ - 15 -

3.2.1 定义PSC设计参数 ........................................................................................................................ - 15 - 3.2.2 定义PSC设计材料 ........................................................................................................................ - 15 -

- 1 -

midas Civil 2010 培训例题

连续梁桥设计专题 3.2.3 定义PSC设计截面位置 ................................................................................................................ - 15 - 3.2.4 定义PSC设计计算书输出内容 .................................................................................................... - 15 - 3.3 PSC设计结果 ............................................................................................................................................. - 16 -

3.3.1 正截面抗弯强度验算 .................................................................................................................. - 16 - 3.3.2 斜截面抗剪强度验算 .................................................................................................................. - 16 - 3.3.3 抗扭强度验算 .............................................................................................................................. - 16 - 3.3.4 正截面抗裂验算 .......................................................................................................................... - 17 - 3.3.5 斜截面抗裂验算 .......................................................................................................................... - 17 - 3.3.6 施工阶段应力验算 ...................................................................................................................... - 17 - 3.3.7 受拉区预应力钢筋拉应力验算 .................................................................................................. - 18 - 3.3.8 正截面压应力验算 ...................................................................................................................... - 18 - 3.3.9 斜截面压应力验算 ...................................................................................................................... - 18 -

- 2 -

midas Civil 2010 培训例题

连续梁桥设计专题 1 桥梁概况

1.1 主要设计指标

该桥是某一级公路上一座(25m+35m+25m)预应力混凝土等截面连续梁桥,横桥向宽度为12.5m,下部结构采用双柱框架墩,承台接钻孔灌注桩基础。

1)桥梁设计基准期100年;

2)结构设计安全等级一级,A类构件; 3)横向布置:双幅桥,双向4车道; 4)桥梁全宽:0.5m(外侧护栏)+11.5m(行车道)+0.5m(内侧护栏)+0.4m(中央分隔带)+0.5m(内侧护栏)+11.5m(行车道)+0.5m(外侧护栏);

5)设计洪水频率:1/300,设计流量:7150m/s;

6)设计恒载:钢结构容重78.5KN/m,钢筋混凝土容重26KN/m,混凝土铺装和沥青混凝土铺装容重24KN/m;

7)可变荷载:

汽车荷载:公路—Ⅰ级车道荷载的均布荷载标准值qk?10.5kN/m;车道荷载集中荷载标准值,Pk?300KN,车道荷载计算剪力效应时,考虑1.2

3

3

3

3

1)二期恒载:

桥面铺装:0.1×11.5×24=27.6 KN/m; 防撞护栏:0.325×26=8.5KN/m; 波形护栏:0.253×26=6.6 KN/m; 横梁实心:4.410×26=114.66 KN/m; 2)预应力管道每米局部偏差对摩擦的影响系数:k?0.0015;

3)对于预应力钢筋与管道壁的摩擦系数:

??0.17 ;

4)钢筋松弛系数,Ⅱ级(低松弛),??0.3; 5)锚具变形和接缝压缩值:?l?6mm(单端);

6)混凝土收缩龄期3天,加载龄期7天; 7)考虑支座不均匀沉降:边跨6.25mm,中跨8.75mm;

8)箱梁的有效宽度按《公路钢筋混凝土及预应力混凝土桥涵设计规范》(JTG D62-2004第4.2.3条计算;

9)竖向日照温差:T1?14℃,T2?5.5℃,竖向日照反温差为正温差乘以-0.5;

10)年最高气温:34℃; 年最低气温:-23℃;施工温度为10℃。

整体升温温差:24℃;整体降温温差:-33℃;

的系数,Pk?1.2?300?360KN;

汽车冲击力:按《公路桥涵设计通用规范》(JTG D60-2004)规定取值。

1.3 相关设计依据

1)《公路工程技术标准》(JTG B01-2003); 2)《公路桥涵设计通用规范》(JTG D60-2004);

3)《公路钢筋混凝土及预应力混凝土桥涵设计规范》(JTG D62-2004);

4)《公路桥涵地基与基础设计规范》(JTG D63-2007);

1.2 相关计算参数

该桥采用后张法预应力施工,结构验算考虑了施工和使用阶段中预应力损失以及预应力、温度、混凝土收缩徐变等引起的次内力对结构的影响。相关计算参数如下所示:

1.4 一般构造及钢束布置

1.4.1 一般构造

结构采用C50混凝土、桥面混凝土铺装采用C50防水混凝土。其轴心抗压强度设计值为fcd?22.4Mpa,轴心抗拉强度设计值为ftd?1.83 Mpa,弹性模量为EC?3.45E?04Mpa。

- 1 -