【作者】 李克银；

【导师】 杨吉新；

【作者基本信息】 武汉理工大学 ， 道路与铁道工程， 2005， 硕士

【摘要】 斜拉桥是高次超静定结构,结构的内力和线型与施工中结构体系和荷载的变化密切相关。随着科技的发展,斜拉桥跨度不断增大,结构更加轻巧,其施工难度随之加大,施工周期变长,导致桥体施工中必然经历寒暑易节的影响以及地震、风和其他施工荷载的激励。因此,在施工中选择合适的监控系统对其结构进行控制与工程成功与否至关重要,而对结构进行静力和动力验算则是施工控制中的核心工作。 本文首先研究了现有施工控制方法的特点,提出了一套斜拉桥专业化监控系统。同时阐述了斜拉桥施工状态结构分析中采用三维模型进行模拟分析的必要性,以及各个构件的等效模拟方法,并介绍了三维空间模型中不同施工工况下使用节点等效荷载的方法。 以三峡库区第一座高低塔斜拉桥(云阳长江公路大桥)为背景,分别建立空间模型和平面模型,进行了静力计算,并从变形、内力、应力和索力等方面分析了同一工况下各个节段和某个节段在不同工况下的变化规律,以及两种模型计算结果之间的差别,为在实际工程中采用适宜的模型进行分析提供了参考。同时鉴于静力分析中,日照温差对结构的影响一直困扰人们的现状,文中提出了在实际施工中应根据实际情况采用不同方法计算结构温度场的观点,并给出了计算公式,同时通过空间模型对最大悬臂状态下的主梁温度影响进行了计算,并与实测数据进行了对比分析,验证了此方法的可靠性。 同时,研究了斜拉桥动力特性的整体特点和用有限元数值分析法对斜拉桥进行动力分析的内容和难点。建立云阳长江公路大桥三维空间动力分析模型,对不同施工状态下的结构进行了动力特性分析,根据其振型和频率,研究了其设计方面的优点以及优化该类型桥梁的思路。通过对几种模型计算结果的对比分析,探讨了该桥在不同施工状态下结构振动的特点,以及在不同激励下的响应。并且,将分析结果推演到成桥状态不同结构体系、不同构件桥梁的动力特性的差异,以期为同类型的桥梁提供借鉴和参考。更多还原

【Abstract】 The cable-stayed bridge is a structure with high degrees, of which internal force and configuration are closed to the structural form and load. With the developing of science, the span of cable-stayed bridge is longer and longer, and the structure is lighter and handy. But the construction will bear cold, heat and same typical dynamic mater, such as seismic response, wind induced vibration and other load in the period of construction. Thus, it attaches importance to choosing a professional construction control system, and the static calculation and dynamic calculation is the core of the construction control.In this thesis, on the basic of studying domestic and international methods of construction control, establish a professional construction control system of cable-stayed bridge. Expatiate the necessity for adopting 3-D space modal in analysis of cable-stayed bridge calculation on construction control state, and introduce the methods of dummy member and how to use node dummy load in different modals.Taking the example of Yunyang Changjiang River Bridge, establish a 3-D space modal, compute and analyze the variety regulation from deformation inner force, stress, and cable tension. Then the distinct between the solutions of the two models is discussed.Because temperature effects that arise in bridges always perplex us in static analysis, it is advisable to choose appropriate methods at different time. In this paper, the temperature effects on the longest cantilever primary beam are computed. In the same time, data from surveying and calculation are made comparison particularly, what verifies the reliability of this method.Three-dimensional dynamic modal is also set up after expatiating the dynamic characteristics of cable- stayed bridges, and the contents of analysis with finite element method. Calculate the dynamic characteristics of the bridge that under different construction case.analyze its vibration dispersion and response when some load affect, discuss its advantages and appropriate ways to optimize the dynamic characteristics. Moreover, these conclusions can be deduced to analyze the distinct of dynamic characteristics between bridges of different structural forms and members, of which may provide reference in bridges of the same structure.更多还原