【作者】 杨帅；

【导师】 王荣辉；

【作者基本信息】 华南理工大学 ， 桥梁与隧道工程， 2015， 硕士

【摘要】 多塔斜拉桥因其独特的结构特点、优美的外观、经济的造价使它在大跨度斜拉桥的建设中越来越受青睐。目前,国内外学者对多塔斜拉桥的研究多停留在设计理论方面,对其施工过程相关问题研究相对较少,本文以在建的江海直达船航道桥为工程背景,进行了以下几方面的研究:(1)三塔钢箱梁斜拉桥合理施工状态的确定。先介绍了5种合理施工状态的计算方法和江海直达船航道桥的施工步骤以及其施工方法的特点难点。然后针对江海直达船航道桥合理施工状态的确定,运用改进后的差值法进行斜拉索初拉力的正装迭代计算,解决了由于结构和荷载不对称,结构整体刚度小等原因引起的个别索索力敏感,运用简单的差值法无法收敛的问题。最后,讨论了主梁定位标高的确定。(2)钢箱梁无应力制造线形计算。基于施工全过程控制思想,对钢箱梁无应力制造线形进行计算研究。在已有制造线形求解方法的基础上,分别推导并计算了大节段吊装施工和悬臂拼装施工的钢箱梁的制造线形和无应力制造尺寸,对这两种施工方法下的钢箱梁的制造线形、安装线形与设计线形进行了对比。(3)结构参数敏感性分析。影响结构受力和变形的参数很多,本文选取了包括荷载、刚度以及温度等参数进行了敏感性分析,了解了这些参数对成桥状态主梁线形,斜拉索索力,钢箱梁、钢塔和拉索应力以及索塔塔顶位移的影响,确定了结构的主要敏感因素为主梁自重、斜拉索张拉力和温度,为后期施工控制误差分析和决策提供依据。(4)江海直达船航道桥合龙问题分析。分析了整体升降温和温度梯度对合龙状态的主梁线形、斜拉索索力、合龙段长度、主梁轴向偏位的影响。分析了合龙顺序变更对成桥状态的主梁线形、索梁塔应力以及塔顶顺桥向位移的影响。针对温度与合龙顺序对结构的影响分别提出了相应调整措施。更多还原

【Abstract】 The unique structural features, beautiful appearance and the economic cost of multi-pylon cable-stayed bridge make it more and more popular in the long span cable-stayed bridge construction. At present, scholars’ study of multi-pylon cable-stayed bridge stays in the design theory,and the relatively study of construction control issues related to them is few. With the background of Jianghai Direct-vessel Channel Bridge in this paper, several aspects are studying as the following:(1)The determination of reasonable construction state of three-pylon steel box girder cable-stayed bridge.Firstly, five calculation methods of reasonable construction state, the construction steps and the characteristics and difficulties of them are introduced. Then the improved difference method is used for the forward iteration calculation of initial cable force, aiming at the determination of reasonable construction state of Jianghai Direct-vessel Channel Bridge. It solves the problem that individual cable is sensitive and it is not convergent by using normal difference method, which caused by the asymmetry of the structure and loads, the small rigidity and other factors. At last, the determination of the main girder’s location elevation is discussed.(2)The calculation of the stress-free fabrication geometry of steel box girders.Based on the overall construction control mind, do a research on the calculation of stress-free fabrication geometry. Based on the existing fabrication geometry calculation methods, derive and calculate respectively the fabrication geometry of the steel box girders installed by large segment hoisting construction and cantilever-splicing construction. And it compares fabrication geometry with installation geometry and design geometry of the steel box girders that are constructed by these two methods.(3)Structure analysis of parameter sensitivity.There are many parameters that can influence the stress and deformation of the structure. This paper chooses some parameters including load, rigidity and temperature to analyze the structure’s sensitivity, know the influence of these parameters on the girder alignment, the cable force, the stress of steel box girders, steel pylons and cables, and the displacement of the top of the pylons and know the sensitive parameters of the structure to provide a basis for later construction control error analysis and decision.(4)Analysis of the closure problems Jianghai Direct-vessel Channel Bridge’s.Analyze the influence of temperature rising, lowering and gradient on the girder alignment, the cable force, the length of closure segments, and the axial deviation of the main girder in the closure state. Analyze the influence of change of closure on the girder alignment, the stress of steel box girders, steel pylons and cables, and the displacement of the top of the pylons. And then put forward several adjustment measures for these influences.更多还原