大跨径混合梁斜拉桥施工控制方法研究

发布时间：2019-05-14 11:14

【摘要】：施工控制是衔接桥梁设计与施工的关键技术环节，桥梁施工控制的主要任务是对桥梁施工过程的线形、应力及索力等内容进行有效的控制和调整，确保在整个施工过程中桥梁结构的内力力和变形始终处于安全、可控及合理的范围之内，并且在成桥以后，桥梁结构的成桥内力和线形均满足设计要求、与理想目标值的误差最小。本文以在建的永川长江大桥为背景开展大跨径混合梁斜拉桥的施工控制方法研究： ①索力—高程控制法。对斜拉桥传统控制方法索力—高程控制法的实施过程进行了简单的介绍，并指出了该方法应用于大跨径混合梁斜拉桥施工控制的局限性。 ②几何控制法。对几何控制法进行了简单的介绍，介绍了几何控制法的基本观点和理论基础；介绍了主塔、主梁单元无应力线形，并对无应力线形的计算方法进行了详细的论述；对拉索无应力索长计算的两种理论进行了详细的介绍：抛物线理论和精确地悬链线理论；详述了如何运用Midas Civil进行几何控制法的施工控制计算。 ③基于几何控制法的大跨径混合梁斜拉桥施工控制的多目标控制法。详细讨论了基于几何控制法的大跨径混合梁斜拉桥施工控制的多目标控制法：以结构无应力几何参数为主要控制对象，中跨钢主梁以几何参数为基本控制目标，以斜拉索无应力索长为主要调控手段；边跨混凝土主梁以力学参数作为基本控制目标，以主梁无应力线形作为线形主要控制手段，以索长、索力双控作为应力调控的全过程控制方法。 ④以永川长江大桥为依托，对基于几何控制法的大跨径混合梁斜拉桥施工控制的多目标控制法的具体实施过程进行了详细的介绍，，并对施工监控的实施结果进行了评价。 ⑤最后对在施工监控中遇到的两个关键问题（边跨混凝土支架的刚度问题、支座摩阻力和边跨混凝土支架摩阻力问题）进行了简单的探讨。混合梁斜拉桥外形美观，具有良好的跨越能力和较强的地形适应性，同等跨度下较全钢箱梁斜拉桥更加经济，实现了“安全、经济、适用、美观”的和谐与统一，在我国桥梁大发展的背景下，有着广泛的应用前景。本文对今后大跨径混合梁斜拉桥的施工监控有较大的参考价值。
[Abstract]:Construction control is the key technical link connecting bridge design and construction. The main task of bridge construction control is to effectively control and adjust the alignment, stress and cable force of the bridge construction process. To ensure that the internal force and deformation of the bridge structure are always in a safe, controllable and reasonable range during the whole construction process, and that after the completion of the bridge, the internal force and alignment of the bridge structure meet the design requirements. The error with the ideal target value is the smallest. In this paper, based on the Yongchuan Yangtze River Bridge under construction, the construction control method of long-span hybrid beam cable-stayed bridge is studied: (1) Cable force-elevation control method. This paper briefly introduces the implementation process of the traditional cable force-elevation control method for cable-stayed bridges, and points out the limitations of the application of this method to the construction control of long-span hybrid beam cable-stayed bridges. 2 geometric control method. This paper briefly introduces the geometric control method, introduces the basic viewpoint and theoretical basis of the geometric control method, introduces the stress-free alignment of the main tower and the main beam element, and discusses in detail the calculation method of the stress-free alignment. Two theories of cable length calculation without stress are introduced in detail: parabola theory and accurate catenary theory, and how to use Midas Civil to calculate the construction control of geometric control method is described in detail. 3. Multi-objective control method for construction control of long-span hybrid beam cable-stayed bridge based on geometric control method. The multi-objective control method of construction control of long-span hybrid beam cable-stayed bridge based on geometric control method is discussed in detail. The stress-free geometric parameters of the structure are taken as the main control object, and the geometric parameters of the middle span steel main beam are taken as the basic control object. The length of cable without stress is taken as the main control method. The mechanical parameters of the side span concrete main beam are taken as the basic control goal, the stress free alignment of the main beam is taken as the main control method, and the cable length and cable force double control are taken as the whole process control method of stress control. Based on Yongchuan Yangtze River Bridge, the implementation process of multi-objective control method for construction control of long-span hybrid beam cable-stayed bridge based on geometric control method is introduced in detail, and the implementation results of construction monitoring are evaluated. Finally, two key problems encountered in construction monitoring (stiffness of side span concrete support, friction resistance of support seat and friction resistance of side span concrete support) are briefly discussed. The hybrid beam cable-stayed bridge has the advantages of beautiful appearance, good leapfrogging ability and strong terrain adaptability, and is more economical than the all-steel box girder cable-stayed bridge under the same span, and realizes the harmony and unity of "safety, economy, applicability and beauty". Under the background of the great development of bridges in our country, there is a wide range of application prospects. This paper has great reference value for the construction monitoring of long-span hybrid beam cable-stayed bridge in the future.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U448.27

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