大跨径斜拉桥桥面线形调整技术研究

发布时间：2018-04-01 14:34

本文选题：桥面线形　切入点：索力调整　出处：《重庆交通大学》2015年硕士论文

【摘要】：斜拉桥作为一种跨越能力强、经济且美观的桥型在近几十年得到了飞速的发展,据不完全统计,在过去的50多年内,全世界修建了300多座大跨径斜拉桥。由于斜拉桥自身的结构特性、使用条件的复杂性加之养护技术的不完善,使得运营阶段的斜拉桥出现了各种各样的病害,在众多的病害之中,运营阶段桥面线形的变化是最为严重的一种。桥面线形在斜拉桥运营过程中具有极其重要的意义,桥面线形的改变将直接关乎到桥梁的结构安全和寿命,同时也会影响行车的舒适度和安全性。本文在对斜拉桥发展历程进行了简要的阐述、运营阶段的斜拉桥的主要病害及其造成这些病害的原因描述的基础上,以武汉长江二桥这一工程实例为依托,提出了基于BP神经网络的斜拉桥非线性随机静力分析方法,分析和研究了影响大跨径斜拉桥跨中下挠的主要因素,及其影响规律,并通过训练得到了武汉长江二桥跨中下挠调整的BP神经网络;引入了一种新的方法——基于神经网络的模糊迭代算法,用来确定斜拉桥合理成桥索力。以武汉长江二桥为算例,用此法对斜拉桥合理成桥索力进行求解,并和零位移法和弯曲能量法确定的成桥索力进行比较,分析其优劣特点,简要说明了在神经网络中考虑随时间变化的因素后得到的索力值对运营阶段的斜拉桥索力调整具有指导作用。在最后根据前面的理论提出了武汉长江二桥桥面线形调整的实施技术方案,该方案的理论计算表明,能完全有效地改变该桥的跨中下挠和索塔的偏移问题。
[Abstract]:The cable-stayed bridge, as a kind of bridge with strong span ability, economy and beauty, has been developed rapidly in recent decades. According to incomplete statistics, more than 300 long-span cable-stayed bridges have been built in the world in the past 50 years.Due to the structural characteristics of the cable-stayed bridge itself, the complexity of the use conditions and the imperfection of maintenance technology, the cable-stayed bridge in the operation stage has appeared a variety of diseases, among which,The change of bridge deck alignment in operation stage is the most serious.The alignment of bridge deck is of great significance in the operation of cable-stayed bridge. The change of bridge deck alignment will directly affect the structural safety and life of the bridge, and will also affect the comfort and safety of driving.Based on the brief description of the development course of cable-stayed bridge, the main diseases of cable-stayed bridge in operation stage and the causes of these diseases, this paper bases on the engineering example of Wuhan No. 2 Yangtze River Bridge.The nonlinear stochastic static analysis method of cable-stayed bridge based on BP neural network is presented. The main factors affecting the mid-span deflection of long-span cable-stayed bridge and its influence law are analyzed and studied.The BP neural network with midspan deflection adjustment of Wuhan Yangtze River Bridge is obtained by training, and a new method, fuzzy iterative algorithm based on neural network, is introduced to determine the rational cable force of cable-stayed bridge.Taking the second Yangtze River Bridge in Wuhan as an example, this method is used to solve the reasonable cable force of cable-stayed bridge, and compared with that determined by zero displacement method and bending energy method, the advantages and disadvantages of the cable force are analyzed.It is briefly explained that the cable force values obtained by taking into account the factors changing with time in the neural network can guide the cable force adjustment of the cable-stayed bridge in the operation stage.In the end, according to the previous theory, a technical scheme for the alignment adjustment of the deck of Wuhan No. 2 Yangtze River Bridge is put forward. The theoretical calculation of the scheme shows that it can completely and effectively change the mid-span deflection of the bridge and the migration of the cable tower.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U448.27

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