大跨径钢管混凝土拱桥易损性分析

发布时间：2018-10-23 11:46

【摘要】：吊杆断裂导致的桥面塌落是目前钢管混凝土拱桥面临的主要病害。本文从吊杆断裂作用和地震作用两个角度对大跨径钢管混凝土拱桥易损性进行研究，基于拓扑易损性和地震易损性分析理论，采用静力弹塑性和非线性增量动力分析方法，对不同吊杆断裂状况和不同地震强度下钢管混凝土拱桥的易损性进行分析研究，并根据分析结果绘制了理论易损曲线，为大跨径钢管混凝土拱桥的设计施工提供指导。主要研究内容如下： (1)基于钢管混凝土拱桥主要病害的归纳分析，剖析了国内外结构易损性分析和吊杆断裂方面的研究现状，明确了大跨径钢管混凝土拱桥易损性分析亟需解决的问题、目的和意义。 (2)基于现有结构易损性理论，探讨钢管混凝土拱桥易损性的分析方法。根据结构拓扑易损性分析理论，分析了局部吊杆失效情况下，进行易损性评价的可行性；对比分析了采用可靠度理论与Pushover分析法建立结构易损曲线和采用增量动力分析法建立结构易损曲线的算法特征和适用场合，推荐了钢管混凝土拱桥地震易损性分析的基本原则和方法。 (3)基于适合钢管混凝土拱桥的易损性分析方法，提出了钢管混凝土拱桥易损性分析流程，，对吊杆断裂的冲击作用和桥面板的延性性能进行了专门研究，确定以相邻吊杆横梁间的相对位移作为桥面板的易损指标，提出了易损性判别准则。 (4)根据拓扑易损性分析的方法，采用半动力的方法考虑吊杆的冲击作用，在考虑恒载、二期荷载和断裂冲击力的作用下，通过对工程实例在不用吊杆断裂组合下进行动力分析，探讨了不同吊杆断裂组合对桥面板的影响，并对基于吊杆断裂的桥面板易损性进行了评价。 (5)针对工程实例，采用纤维模型考虑桥面板的材料非线性，选取合适的地震波，对计算模型进行非线性增量动力分析，通过对分析结果的进行线性拟合，建立理论易损性曲线，并对所得地震易损性曲线进行了对比分析。
[Abstract]:The collapse of deck caused by the rupture of suspenders is the main disease of CFST arch bridge at present. In this paper, the vulnerability of long-span concrete-filled steel tube arch bridge is studied from the angle of suspender fracture and seismic action. Based on the theory of topological vulnerability and seismic vulnerability, the static elastic-plastic and nonlinear incremental dynamic analysis methods are used. The vulnerability of concrete-filled steel tubular arch bridge under different suspenders and different earthquake intensity is analyzed and studied, and the theoretical vulnerable curve is drawn according to the analysis results, which provides guidance for the design and construction of long-span concrete-filled steel tube arch bridge. The main research contents are as follows: (1) based on the induction and analysis of the main diseases of concrete-filled steel tubular arch bridge, the research status of structural vulnerability analysis and suspender fracture at home and abroad is analyzed. The problems, purpose and significance of vulnerability analysis of long-span concrete-filled steel tubular arch bridge are defined. (2) based on the theory of structural vulnerability, the method of vulnerability analysis of concrete-filled steel tubular arch bridge is discussed. According to the theory of structural topology vulnerability analysis, the feasibility of vulnerability evaluation is analyzed under the failure of local suspenders. In this paper, the characteristics and application of reliability theory and Pushover method are compared to establish the structural vulnerability curve and incremental dynamic analysis method to establish the structural vulnerability curve. The basic principles and methods of seismic vulnerability analysis of CFST arch bridges are recommended. (3) based on the analysis methods suitable for CFST arch bridges, the flow chart of vulnerability analysis of CFST arch bridges is presented. The impact action of boom fracture and the ductility of bridge deck are studied specially, and the relative displacement between adjacent suspension beams is determined as the vulnerable index of bridge deck. The criterion of vulnerability is put forward. (4) according to the method of topological vulnerability analysis, the semi-dynamic method is adopted to consider the impact of the suspender, under the action of dead load, second stage load and fracture impact force. Based on the dynamic analysis of engineering examples without the combination of suspenders, this paper discusses the influence of different combination of suspenders on the bridge deck slab, and evaluates the vulnerability of the bridge deck slab based on the breakage of the suspenders. (5) aiming at the engineering examples, the paper makes an evaluation of the vulnerability of the bridge deck slab based on the breakage of the suspenders. The fiber model is used to consider the material nonlinearity of the deck slab and the appropriate seismic wave is selected. The nonlinear incremental dynamic analysis of the calculation model is carried out. The theoretical vulnerability curve is established by linear fitting of the analysis results. The seismic vulnerability curves obtained are compared and analyzed.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U441.6;U448.22

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