高速铁路大跨度钢管混凝土连续梁拱桥抗震性能研究

【作者】 莫朝庆；

【导师】 叶梅新； 罗如登；

【作者基本信息】 中南大学 ， 结构工程， 2008， 硕士

【摘要】 跨骝涌水道大桥为广深港客运专线上的一座连续梁拱桥,跨径组合为(76+160+76)米,主桥采用预应力混凝土连续梁与钢管混凝土拱组合结构的新型结构形式。桥址场地土以软土为主,场地类别为Ⅲ类,地震设防烈度为Ⅶ度,其抗震问题必须予以重视。目前我国规范对大跨度钢管混凝土拱桥的抗震问题无明确规定,因此对其进行抗震性能的研究具有重要的实际意义。本文以跨骝涌水道大桥为研究对象,主要完成了如下工作:1、根据跨骝涌水道大桥结构构造特征,探讨了拱肋、横撑、支座连接方式和桩土相互作用的模拟方法,建立了动力分析模型,对该桥的动力特性进行了研究。2、对跨骝涌水道大桥进行了反应谱分析,采用标准反应谱曲线分析计算了结构在多遇地震、设计地震和罕遇地震最不利荷载组合作用下结构的位移、内力和应力,并与双线活载作用下的静力分析结果进行了对比,对该桥在多遇、设计和罕遇地震荷载作用下的抗震性能做出了评估。3、对跨骝涌水道大桥进行了时程分析,采用TAFT-69°波分析了结构在多遇地震、设计地震和罕遇地震荷载作用下结构的内力、位移和应力,检算了结构抗震安全性。将时程分析的结果与反应谱分析结果进行了对比,对两种方法的适用性进行了研究。4、探讨了横撑、吊杆形式(竖直、倾斜和网状吊杆)和桩土相互作用对大跨度连续梁拱桥动力特性和地震响应的影响,为同类桥梁的抗震优化设计提供了的参考。本文的研究成果为跨骝涌水道大桥的设计提供了依据,对其它类似的大跨度钢管混凝土结构抗震设计也有参考价值。更多还原

【Abstract】 Liu Yong Shuidao Bridge(LYSB) is a continuous beam-arch bridge in the dedicated passenger line of Guang Zhou to Hong Kong, and span of the bridge is (76+160+76)m. The structure of main span is Prestressed concrete continuous box beam and concrete-filled steel tube arch. Site soil of LYSB is soft soil; site classification is III; seismic fortification intensity is 7 degree. So the earthquake resistance design should be pay more attention. However, the earthquake resistance design of Long-span arch bridge of CFST is not clearly regulated in the current code. So the study of aseismatic performance for Long-Span arch bridge of CFST has practical significance.Based on LYSB, main work of this paper is as follows:1. According to the structure characteristics of LYSD, simulation of transversal girder, boom and the effect of pile-soil interaction were studied. The finite element model of the bridge was made using midas. Structural dynamic characteristics were studied.2. Using the standard seismic response spectrum, the responses of LYSB to response spectrum analysis were studied. The internal forces, stresses and displacements of structural crucial sections under frequently-occurred earthquake, design earthquake and rare earthquake were analyzed. Beside, the results of earthquake were compared with the results of static analysis under double-track railway live load. It shows that the bridge meets the demand of the code under three kinds of earthquake, and bridge earthquake resistance design does not control the design of LYSB.3. Using Taft-69°seismic wave, the responses of LYSB to time history analysis were studied. The internal forces , stresses and displacements of the structural crucial sections under common occurred earthquake, design earthquake and rare earthquakes were analyzed. The safety of the bridge was checked. Beside, the results of response spectrum analysis were compared with the results of time-history analysis. Some beneficial conclusions are gained.4. The influence that the structure of transversal girder, boom and the effect of pile-soil interaction to dynamic characteristics and dynamic responses of long span concrete filled steel tubular arch bridge was discussed. Some beneficial conclusions are gained, which could provide some references for the dynamic analysis and optimization design of other similar bridges.The research results of this paper can service design of LYSB and provide references for other similar structures.更多还原