大跨度斜拉桥减震策略分析

发布时间：2018-06-20 13:00

本文选题：大跨度 + 斜拉桥　；参考：《重庆交通大学》2015年硕士论文

【摘要】：桥梁通常是交通运输的枢纽工程,对国民经济有着重大影响,其抗震问题早已是工程界最关心、最具有挑战性的课题之一。随着桥梁建设技术的不断进步,大跨度斜拉桥发展迅猛,相应的大跨度斜拉桥抗震问题就受到越来越多的关注。而大跨度斜拉桥的抗震性能与其减震策略直接相关,包括纵桥向减震策略和横桥向减震策略。因此,研究大跨度斜拉桥纵、横两个方向合理有效的减震策略,以确保其在地震中的安全性,具有十分重要的经济意义和社会价值。自结构振动控制概念提出以来,利用阻尼器吸能、耗能的一系列机械装置得到了飞速的发展。其中得到较早研究与应用的一类控制技术为被动控制技术,如如液压粘滞阻尼器、金属阻尼器、摩擦摆式装置等等。其因概念简单,机理明确,减震效果明显,并且经济实用,在工程实践中得到广泛应用。综合起来,本文结合一座主跨600米的双塔斜拉桥进行减震策略分析,主要开展了以下几方面的研究工作:(1)采用结构分析程序SAP2000建立了三维有限元模型,同时考虑几何非线性、桩土相互作用的影响,进行动力特性分析。采用与规范标准反应谱匹配良好的7条人工地震波作为地震动参数,分别进行纵向+竖向、横向+竖向这两种输入下的桥梁结构动力时程反应分析。(2)为开展大跨度斜拉桥纵桥向合理减震策略研究,首先详细介绍了飘浮体系/半飘浮体系斜拉桥纵桥向简化分析方法。然后从常用的两种减震方式(粘滞阻尼器和弹性索)出发,对该大跨度斜拉桥进行纵桥向减震策略分析,对减震的关键设计参数进行了探讨,分析了对结构地震响应的影响,为大跨度斜拉桥的减震设计提供了理论依据。最后,根据本文的分析结果,提出了大桥减震装置参数建议值。(3)为开展大跨度斜拉桥横桥向合理减震策略研究,首先从理论与数值上分析了大跨度斜拉桥横桥向抗震体系中全限位体系和全滑动体系的不合理性,指出了减震体系的优势,然后依托本工程实例,选取了具有代表性的三种减隔震装置,详细探讨了不同减震装置的减震原理、参数选取及优化问题,最后对比分析了不同减震体系的优劣,为工程应用提供了数据支撑与实用参考。
[Abstract]:Bridge is usually the hub of transportation, which has a great impact on the national economy. The seismic problem of bridge has been one of the most concerned and challenging topics in the engineering field. With the development of the bridge construction technology, the long-span cable-stayed bridge is developing rapidly, and the seismic problem of the long-span cable-stayed bridge is paid more and more attention. The seismic performance of long-span cable-stayed bridge is directly related to its damping strategy, including longitudinal bridge damping strategy and transverse bridge damping strategy. Therefore, it is of great economic significance and social value to study the reasonable and effective seismic mitigation strategy of long-span cable-stayed bridge in longitudinal and horizontal directions in order to ensure its safety in earthquake. Since the concept of structural vibration control was put forward, a series of mechanical devices using dampers to absorb energy have been developed rapidly. Among them, passive control techniques have been studied and applied earlier, such as hydraulic viscous dampers, metal dampers, friction pendulum devices and so on. It is widely used in engineering practice because of its simple concept, clear mechanism, obvious shock absorption effect, and economic and practical application. In this paper, combined with a 600m main span double-tower cable-stayed bridge, the main research work is as follows: (1) A three-dimensional finite element model is established by using the structural analysis program SAP2000, and geometric nonlinearity is taken into account. The dynamic characteristics of pile-soil interaction are analyzed. Seven artificial seismic waves, which are well matched with the standard response spectrum, are used as ground motion parameters. Dynamic time-history response analysis of bridge structure under transverse vertical input. 2) in order to carry out the research on longitudinal reasonable vibration absorption strategy of long-span cable-stayed bridge, the simplified analysis method of longitudinal bridge with floating system and semi-floating system is introduced in detail. Then, based on two commonly used damping methods (viscous dampers and elastic cables), the longitudinal vibration reduction strategy of the long-span cable-stayed bridge is analyzed, the key design parameters of the damping are discussed, and the influence on the seismic response of the structure is analyzed. It provides a theoretical basis for the design of large span cable-stayed bridge. Finally, according to the analysis results of this paper, it is put forward that the suggested value of vibration absorber parameters of the bridge should be. 3) to carry out the research on the reasonable seismic absorption strategy of the transverse bridge of the long span cable-stayed bridge. In this paper, the irrationality of full limit system and full sliding system in the transverse seismic system of long span cable-stayed bridge is analyzed theoretically and numerically, and the advantages of the damping system are pointed out. Three representative isolation devices are selected, and the principle, parameter selection and optimization of different shock absorbers are discussed in detail. Finally, the merits and demerits of different damping systems are compared and analyzed. It provides data support and practical reference for engineering application.
【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】：U442.55;U448.27

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