摘要：本次设计是关于跨径为35+55+35m的一座高速铁路连续刚构桥的上部结构。该桥线路形式为双线，线间距为4。6m，主梁采用单箱单室的箱梁截面，梁底下缘及底板上缘均按抛物线规律变化。桥面横向宽度为13。3m，主墩墩顶梁高3m，跨中梁高1。25m。主梁施工采用悬臂施工法，边跨现浇段施工采用满堂支架法。由于设计计算需要考虑连续刚构桥在每个施工阶段的荷载情况和施工过程中的体系转换问题，计算内容复杂，手算效率低，准确性又无法保证，因此需要借助midas Civil软件。通过该软件，首先可以建立真实情况的连续刚构桥模型，模拟施工过程，模拟荷载作用，并能按照规范进行荷载效应组合，计算出相应的内力值。然后取最不利荷载组合下的结构内力包络图，对预应力钢束进行估算，再由PSC设计结果对其进行布置和调整。最后，对截面强度进行验算。71918

毕业论文关键词：高速铁路；连续刚构桥；迈达斯；内力计算

Design for a rigid frame bridge which has a span of (35+55+35) meters is used on a high speed railway

Abstract:This is related to the upper structure of a high-speed railway continuous rigid frame bridge with a span of (35+55+35) meters。The railway bridge has double tracks, there is a distance of 4。6 meters between them。Bridge girder cross-section is designed to a shap of single-box-single-cell, the lower edge of the beam bottom and the bottom edge of the floor changes according to the parabolic law。The width of the bridge deck is 13。3m, the beam in the main pier is 3m high and the middle beam is 1。25m high。Construction for the main beam uses cantilever construction method, but for the side of the cast-in-place is full-frame method。Both the load conditions at each construction stage and the system conversation problem in work progress should be taken into consideration, the design calculation for continuous rigid frame bridge is complex。Efficiency for manual calculation is low, and the accuracy can not be guaranteed, so we need to use midas Civil software。Through this software, we can first establish the model of continuous rigid frame bridge, simulate the construction process, simulate the load effect, and it can also carry out the load effect combination according to the specification, calculate the corresponding internal force value。Then, according to the internal force envelope under the most unfavorable load combination, the prestressed steel beam is estimated and then the prestressed steel beam is arranged and adjusted by PSC design。Then, according to the internal force envelope under the most unfavorable load combination, the prestressed steel beams are estimated and then they are arranged and adjusted by PSC design。 Finally, the cross section strength should be checked。

Keywords: high-speed railway;continuous rigid frame bridge;Midas;internal force calculation

目  录

1绪论 1

1。1 连续刚构桥概述 1

1。1。1 受力特点 1

1。1。2 构造特点 1

1。2 悬臂法施工介绍 2

1。2。1 施工特点 2

1。2。2 简要施工工序 2

1。3 midas Civil简介 2

1。4 设计概述 3

1。5 毕业设计的目的和意义 4

2桥跨整体设计和施工 5

2。1 主梁结构尺寸设计