城市混合梁斜塔斜拉桥设计分析

发布时间：2018-06-15 06:40

本文选题：斜拉桥 + 斜塔　；参考：《西南交通大学》2015年硕士论文

【摘要】：近年来,斜塔斜拉桥因其桥塔新颖别致、造型流畅轻盈,在小跨径、宽桥面的城市桥梁中脱颖而出。混合梁桥因其跨越能力优秀、充分利用材料特性、能够加快施工进度等特点越来越受到桥梁设计师的广泛关注。本文以文博路水库大桥为背景,通过有限元软件MidasCivil建立空间杆系模型对该混合梁斜塔斜拉桥系统地进行了静力分析和稳定分析。研究表明,对于斜塔斜拉桥,梁截面梯度温差对混凝土梁的受力影响较大。由于塔身倾斜导致桥塔弯矩较大,故塔柱截面较为粗壮,桥塔不易发生失稳。同时主梁失稳对应临界荷载系数较大,因此采用混合梁斜塔方案可有效提高斜拉桥的稳定性。采用混合梁方案可以提高结构的抗震性能,但塔身倾斜不利于桥塔的抗震。基于反应谱理论和动态时程理论对结构的地震响应进行分析,桥塔属于结构抗震设计中的薄弱环节,重现期较长地震发生时塔底有发生破坏的风险。通过有限元软件ANSYS建立钢箱梁局部模型对钢桥面板进行第二、三体系受力分析。为了确定车轮荷载对于该受力体系的最不利加载方案,提出“影响评级系数”评价体系。在此基础上改变钢箱梁顶板、顶板纵肋与横隔板厚度进行离散性对比分析。研究表明,城市宽桥面斜拉桥结构横向效应非常突出,适当增加横隔板厚度可有效地改善钢桥面板的横向受力问题。
[Abstract]:In recent years, the cable-stayed bridge with inclined tower is distinguished from the city bridge with small span and wide deck because of its novel tower and light shape. Bridge designers pay more and more attention to hybrid beam bridge because of its excellent span ability, making full use of material characteristics and accelerating construction progress. Taking Wenbo Road Reservoir Bridge as the background, the static and stability analysis of the hybrid girder cable-stayed bridge with inclined tower is carried out systematically by the finite element software Midas Civil. The results show that the gradient temperature difference of the beam section has a great influence on the stress of the concrete beam for the inclined tower cable-stayed bridge. Because of the larger bending moment of the tower caused by the inclined tower, the section of the tower column is relatively strong, and the tower is not easy to lose stability. At the same time, the stability of cable-stayed bridge can be improved effectively by adopting the scheme of hybrid beam inclined tower, because the corresponding critical load coefficient of the main beam instability is large. The hybrid beam scheme can improve the seismic performance of the structure, but the tilting of the tower is not conducive to the seismic behavior of the bridge tower. Based on the response spectrum theory and the dynamic time history theory, the seismic response of the structure is analyzed. The bridge tower belongs to the weak link in the seismic design of the structure. The local model of steel box girder is established by finite element software ANSYS. In order to determine the most unfavorable loading scheme of wheel load to the load system, an evaluation system of "influence rating coefficient" is put forward. On this basis, the thickness of longitudinal rib and transverse partition of steel box girder is compared and analyzed. The research shows that the transverse effect of cable-stayed bridge structure with wide deck is very prominent and the transverse force of steel bridge slab can be effectively improved by increasing the thickness of transverse diaphragm.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U448.27

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