π型梁曲线斜拉桥弯梁效应阈值分析研究

发布时间：2019-05-12 17:56

【摘要】：曲线斜拉桥主梁呈现明显的弯梁桥特点,同时又是多次超静定空间缆索承重体系,因此曲线斜拉桥的受力非常复杂,具有高度的空间性。由于曲率的存在,曲线斜拉桥必然存在弯扭耦合效应。当曲线斜拉桥的曲率较小时,主梁弯扭耦合效应不明显,其力学行为与同跨度的直线斜拉桥差别不大,设计时可忽略弯扭耦合效应的影响,按直线斜拉桥进行设计。若曲率较大,主梁弯扭耦合效应明显,可能出现扭矩过大、支座脱空等现象,此时结构不能按照直线斜拉桥进行设计。论文依托非洲刚果(布)布拉柴维尔滨河大道曲线斜拉桥实际工程项目,使用专业桥梁有限元软件Midas/Civil进行数值模拟和计算,进行曲线斜拉桥弯梁效应阈值研究,主要工作内容包括:1、分析研究曲线梁桥和斜拉桥的结构分析理论,在此基础上,归纳曲线斜拉桥弯梁效应阈值的计算理论和分析方法;2、分析静力指标对曲率半径和弧长的敏感性,从而确立曲线斜拉桥弯梁效应阈值分析评判指标;3、分析曲线斜拉桥能够按照直线斜拉桥设计时的弯梁效应上限阈值和完全不能按照直线斜拉桥设计时的弯梁效应下限阈值,并分析结构的不确定性参数对弯梁效应阈值的影响;4、开展不同弧长和塔高参数下的曲线斜拉桥弯梁效应阈值研究,给出弯梁效应阈值与弧长和塔高之间的关系曲线和公式。
[Abstract]:The main beam of curved cable-stayed bridge has obvious characteristics of curved beam bridge, and at the same time it is multi-statically indeterminate spatial cable-bearing system. Therefore, the force of curved cable-stayed bridge is very complex and has a high spatial character. Due to the existence of curvature, curved cable-stayed bridge must have bending and torsional coupling effect. When the curvature of the curved cable-stayed bridge is small, the bending-torsion coupling effect of the main beam is not obvious, and the mechanical behavior of the curved cable-stayed bridge is not much different from that of the linear cable-stayed bridge with the same span. If the curvature is large, the coupling effect of bending and torsional of the main beam is obvious, and the torque may be too large and the support is empty. At this time, the structure can not be designed according to the linear cable-stayed bridge. Based on the actual engineering project of curved cable-stayed bridge along Brazzaville River Avenue in Africa, this paper uses the professional finite element software Midas/Civil to simulate and calculate the curved beam effect of curved cable-stayed bridge, and studies the threshold value of curved beam effect of curved cable-stayed bridge. The main work contents are as follows: 1. The structural analysis theory of curved beam bridge and cable-stayed bridge is analyzed and studied. On this basis, the calculation theory and analysis method of curved beam effect threshold of curved cable-stayed bridge are summarized. 2. The sensitivity of static index to curvature radius and arc length is analyzed, and the threshold value of curved beam effect of curved cable-stayed bridge is established. 3. It is analyzed that the curved cable-stayed bridge can be designed according to the upper limit threshold of bending beam effect in the design of linear cable-stayed bridge and the lower limit threshold of bending beam effect in the design of linear cable-stayed bridge. The influence of the uncertain parameters of the structure on the threshold of bending beam effect is analyzed. 4. The threshold of bending beam effect of curved cable-stayed bridge under different arc length and tower height parameters is studied, and the relationship curve and formula between bending beam effect threshold and arc length and tower height are given.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U448.27

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