【作者】 韩立中；

【导师】 张哲；

【作者基本信息】 大连理工大学 ， 桥梁与隧道工程， 2009， 博士

【摘要】 近年来,随着交通科技的发展各种各样的桥型也随即产生,大跨径悬索桥与大跨径斜拉桥更是发展迅速。但是随着桥梁所处的空间、施工条件以及经济造价的限制,这些大跨径桥型越来越受到限制;桥型多样化,空间结构桥梁增多是桥梁发展的趋势所在。新工艺、新材料和高性能计算机的出现,使得与桥梁设计相关理论在近三十年得以迅速发展、完善。概念设计方面:经过解析与数值分析理论的发展,明确了典型结构体系的力学特性,涌现了各种样式悬索桥、斜拉桥,协作体系桥梁。自锚式、地锚式悬索桥以其优美的线型、新颖的外观以及选址灵活等特点受到大家喜欢。地锚式悬索桥虽然是大跨径甚至超大跨径桥梁的首选,但是它那硕大的锚碇受到施工以及经济的制约越来越让人们伤透脑筋。自锚式悬索桥而越来越受到青睐,一大批大跨度自锚式悬索桥也就应运而生。但是受到材料以及力学体系的限制跨径也受到很大制约,只能在中小跨径徘徊。斜拉桥的跨径也作的越来越大,已经超过千米的斜拉桥世界上也有好几座,发展势头也锐增。斜拉桥的刚度以及挺拔的力度也受到人们的青睐,在中小跨径以及大跨径桥梁,跨江、跨海等地理位置复杂的地形、还有风速以及地震恶劣环境条件下的地形都能看到斜拉桥挺拔的身影。但是斜拉桥随着跨径的增加,随着力学体系要求,斜拉桥的塔高越来也越高,千米级斜拉桥的塔高达到350多米甚至400米,这么高的普通建筑都受到力学和环境的挑战,何况还受到静力以及动力不断施加的桥梁,施工难度以及监控相当复杂。况且还有地形以及航空管制等外界事物的必然限制。综合以上很多因素的考虑,基于大连湾跨海大桥的实例,大连理工大学课题组提出了自锚式斜拉.悬索协作体系桥梁来解决相应的问题,还受到交通部西部交通建设科技项目“斜拉-悬索协作体系桥梁的研究”开发课题的资金资助。西部交通建设科技项目基金(2006 318 823 50)。自锚式斜拉—悬吊协作体系桥作为一种新型的桥梁结构形式,具备了传统的斜拉—悬吊协作体系桥的诸多优点,而且由于庞大锚碇的取消,更好的适应了深海软土地基的建设,在不良地质环境条件下具有强劲的竞争力,目前已被工程界所采纳。但从已有的文献看,对这种桥型静、动力性能的研究颇为少见。为了确保自锚式斜拉-悬索桥施工和成桥运营期间的安全,使得自锚式斜拉-悬索桥结构的设计更加经济合理,本文以拟建的大连湾跨海大桥以及金州湾跨海大桥为工程背景,基于几何非线性有限元理论、图论优化理论,对大跨度自锚式悬索桥整体稳定与极限承载力、结构动力特性、地震响应分析、抗震减震、颤振稳定、抗震可靠度、结构系统可靠度等几个方面开展了大跨度自锚式斜拉-悬索桥分析方法与性能方面的研究。本文的研究工作和取得的主要成果有:1.结合设计基本资料及设计技术要求,提出了大连湾跨海大桥桥型方案的设计构思,并对大桥自锚式斜拉-悬索桥的结构体系进行了创新性设计。2.本文将图论应用于薄壁杆件结构计算,建立了薄壁剖面的图模型,利用关联矩阵和基本回路矩阵简洁而又准确地描述了薄壁剖面的拓扑关系。利用图论导出的计算扇性坐标、Bredt剪流、二次剪流和弯曲剪流的矩阵方程式。对任意复杂的薄壁剖面,只要建立了图模型,得到关联矩阵和基本回路矩阵,就可利用以上各矩阵方程式方便地用电子计算机求解,从而避免了在具体计算过程中判断剖面的拓扑关系而引起的困难。用图论作工具,研究了薄壁杆件在自由扭转时剖面极限扭矩的计算方法。3.分析研究了悬索桥、斜拉桥、自锚式斜拉悬索桥的相关理论。本文选择大型通用有限元程序ANSYS作为结构分析软件,在求解过程中计入上述各种非线性因素的影响,以大连湾跨海大桥大连港主通航孔为工程背景,建立平面杆系计算模型。把自己分析的梁柱效应理论、虚位移原理应用于自锚式斜拉悬索桥力学分析当中,结合ANSYS有限元软件,更好分析此桥产生的非线性力学效应。4.基于有限元理论,考虑多种非线性因素,建立有限元模型,对大连湾跨海大桥大连港主通航孔推荐方案主跨800m的自锚式斜拉—悬索协作体系桥的静力行为进行了详尽分析,包括刚度特性、内力、吊索疲劳问题、交接区的变形。5.自锚式斜拉—悬吊协作体系桥的动力特性主要包括体系的自振频率和主振型,它是该体系桥进行动力响应分析的前提和基础。通过建立空间有限元计算模型,对采用自锚式斜拉—悬吊协作体系的大连港跨海大桥的动力特性进行了分析,并与相同跨径和结构参数的地锚式斜拉—悬吊协作体系桥进行了对比研究,总结了自锚式斜拉—悬吊协作体系桥动力特性的新特点并揭示了其原因。6.分别用反应谱方法和时程分析方法对大连港海湾大桥拟定的结构体系进行了抗震分析。根据抗震分析结果,选定了结构体系,采用了摩擦支座减震技术,并对粘滞阻尼技术进行了探讨。本文将精确高效的虚拟激励法引入到自锚式斜拉—悬吊协作体系桥的地震响应分析中,对此桥在随机地震荷载作用下的地震响应进行了系统地研究,重点考察了三种影响地震体系波作用下,考虑了多点激励和地震动的空间变化效应以及阻尼的变化对该新型体系内力和位移峰值的影响。以大连湾跨海大桥为例,基于由规范反应谱生成的当量功率谱密度函数,对比分析了多点一致激励和非一致激励下其地震响应的特点和规律,所得结论为该新型协作体系桥的抗震设计提供了有价值的参考。鉴于阻尼作为结构动力特性及动力反应中的一个重要参数,本章研究了阻尼器地选择,作者主要言裾持妥枘崞?介绍了粘滞阻尼器地原理及其应用方法,研究了阻尼比的变化对结构地震反应的影响。为该新型体系桥梁的进一步设计提供了有价值的参考。7.针对大跨度自锚式斜拉-悬索桥可能存在的风致振动,对大连港海湾大桥进行了颤振稳定分析。本文简要介绍了桥梁静力风效应与桥梁风致振动的基本理论,以大连湾跨海大桥为工程背景,通过理论分析对大跨度自锚式悬索桥的抗风性能进行了研究。主要研究①运用多模态颤振有限元分析方法,分别从悬索的矢跨比、吊跨比、斜拉索索面布置形式、边跨辅助墩的设置以及桥面主梁构成等设计参数着手,对主跨800m的一座自锚式斜拉-悬吊协作体系桥进行了颤振稳定性分析,指出了影响自锚斜拉-悬吊协作体系桥颤振稳定性的关键设计参数,并从抗风性能角度探讨了自锚斜拉-悬吊协作体系桥的合理结构形式。②由变形引起的结构动力特性以及空气力的非线性变化效应将会对大跨径自锚式-斜拉悬索桥的颤振产生不容忽视的影响。基于结构的变形后状态,充分考虑结构变形引起的非线性效应,建立了大跨径桥梁颤振分析的三维非线性方法及其计算程序。结合大连湾跨海大桥设计的自锚式斜拉-悬索桥进行了颤振分析和研究,并揭示了结构变形产生的非线性效应对大跨径自锚式斜拉悬吊桥颤振影响的程度和机理。8.本文以大连湾跨海大桥作为研究对象,引入虚拟激励法,对自锚式斜拉悬索桥的抗震动力可靠度进行了计算分析。分别计算了考虑均匀地面激励、空间效应及任意相干效应的情况,在多点非一致激励下的桥梁下部结构的墩、塔各控制截面的抗震动力可靠度,得到了一些有价值的结论。9.本文总结了结构系统可靠度分析的方法及失效模式。对大连湾自锚式斜拉悬索协作桥在承载能力极限状态下的系统可靠度进行了评估。采用全局β约界法识别结构系统的主要失效模式,并应用微分等价递归算法得到系统各失效模式的等价安全裕量方程。最后,通过Ditlevsen界限理论,确定了结构系统失效概率的上、下限。更多还原

【Abstract】 In recent years, with the development of traffic technology, then the development of variety of bridge-type is also produced, long-span suspension bridge with long span cable-stayed bridge is developing rapidly. But, because space for the construction of a bridge, construction conditions and the economic cost are restricted, these long-span bridge types have increasingly constrained; bridge-type diversification and the increase in space-bridge structure are the trend of the bridge development. With new technology, new materials and the emergence of high-performance computer, making the theory of bridge design to become the rapid development and improvement in the last three decades.Aspects of bridge conceptual design: through development of the analytical and numerical analysis theory, defining mechanical properties of the typical structural system, a variety of style of suspension bridge, cable-stayed bridge and cooperative system is the emergence. Self-anchored and ground-anchored suspension bridges are liked by everyone with its graceful linear, the appearance of novel and flexible bridge site. The ground-anchored suspension bridge is the first choice for long-span and super-long-span bridge design, but, is more and more worried by people because of its construction of huge anchorage, and economic constraints. Because self-anchored suspension bridge is more and more liked by people, a large number of large-span self-anchored suspension bridges also came into being. However, because of constraints of materials and mechanical systems, long-span self-anchored suspension bridge has been greatly restricted, self-anchored bridge is only the small and medium-span bridge. The long-span cable-stayed bridges are also more and more built. Cable-stayed bridge of more than 1000 meters span has become in the world, trends of development is a sharp increase. Cable-stayed bridge is liked by people because of its stiffness and strength of tall and straight, is be able to made everywhere in the small and medium span, long-span bridges, crossing river, across the sea, the complex geographic terrain, as well as wind and seismic harsh environmental conditions of the terrain. However, the increase with cable-stayed bridge span, requirements with the mechanical system, cable-stayed bridge tower more and more is higher, height of the tower of cable-stayed bridge more than 1000 meters span has reached more than 350m or 400m, such a high general building is challenged by mechanical and environmental, the bridge is more affected because of static and dynamic continuing imposing, construction of difficulty and monitoring of quite complex. Moreover, it is restricted inevitably by terrain, as well as air traffic control and the external things etc. Taking consideration of the above many factors, based on examples of Dalian Bay Bridge, Dalian University of Technology Task Force presented a self-anchored cable-stayed-suspension collaboration system bridge project to solve the corresponding problems, but also affected by development funding issues by western transportation construction projects " Cable-stayed-suspension bridge research cooperative system " of the Ministry of Communications in China. Western Transportation Construction Science and Technology Project Fund Number (200,631,882,350).Self-anchored cable-stayed-suspension bridge of a new type of bridge structure has now been adopted by the engineering sector, because of many advantages of the traditional cable-stayed-suspension bridge, and a strong competitive edge due to the cancellation of a large anchorage, better adapting to the construction of deep-sea and soft soil in the bad conditions of geological environment, however, the existing literature of view, the research for this bridge-type static and dynamic properties is quite rare. The paper has carried out several research on large-span self-anchored cable-stayed- suspension bridge on the overall stability, ultimate bearing capacity, structural dynamic characteristics of seismic response analysis, seismic vibration, flutter stability, seismic reliability degrees, the structural system reliability etc, In order to ensuring self-anchored cable-stayed-suspension bridge construction, and the safety during the operation, making self-anchored cable-stayed-suspension bridge structural design more economical and reasonable, based on geometric nonlinear finite element theory, graph theory, optimization theory, with background of Dalian Bay Bridge and Jinzhou Bay Bridge engineering. Work and major achievements of this paper are:(1) Based on the basic design data and requirements, the designs on the new type of structural system of Dalian bay Bridge are proposed. A lot of creationary achievements will be acquired on Dalian Bridge, called the single tower self-anchored suspension bridge.(2) This paper applied graph theory to thin-walled structure calculation, and established a thin-walled cross-section of the graph model, described succinctly and accurately the topolog -ical relations of thin-walled cross-section in correlation matrix and the basic loop matrix. And derived coordinates of fan features, matrix equation of bredt shear flow、secondary shear flow and the bending shear flow in graph theory. Studied calculations of the thin-walled cross-section limit torque in the free torsion in graph theory.(3) Carried out analysis of the relevant theory of the suspension bridge, cable-stayed bridge, self-anchored cable-stayed suspension bridge. This paper make use of large-scale general finite element program ANSYS, included in the above-mentioned non-linear factors in the solution process, with Dalian Main Navigation bridge Dalian Port for the engineering background, establishing plane frame calculation model. Carry out self-anchored suspension bridge mechanical analysis in beam-column effect theory and theory of virtual displacement principle, better analyzed this non-linear mechanical effects generated by the bridge with ANSYS finite element software.(4) Based on finite element theory, considering a variety of non-linear factors, establishing the finite element model, carried out a detailed static behavior analysis to self-anchored cable-stayed-suspension bridge of Dalian Bay Bridge of main span of 800m, including stiffness, internal forces, sling fatigue, deformation of transfer zone.(5) Dynamic characteristics of self-anchored cable-stayed suspension bridge mainly include natural vibration frequencies and principal modes, which are the base and precondition of dynamic response analysis for the kind of the system bridge. Dynamic characteristics of Dalian bay bridge, belonging to self-anchored cable-stayed suspension system, are analyzed and compared with those of earth-anchored cable-stayed suspension bridge with the same span and structure parameters by using spatial finite element model, some new traits of dynamic characteristics for the system bridge are summarized and the reasons are discovered.(6) By applying highly efficient pseudo excitation method, the dissertation analyzes random seismic response of self-anchored cable-stayed suspension bridge under P wave, SH wave and SV wave excitation and the influences on the peak values of internal forces and displacements of some factors such as multiple-support excitation and seismic spatial effect and varieties of damping ratio are considered. Subjected to multiple-support uniform and non-uniform excitation, the traits and regulations of seismic response for Dalian bay bridge are compared on basis of the equivalent power spectrum density function made by criterion response spectrum, conclusions drawn provide some valuable references for the anti-seismic design of the new type of bridge. In view of the damping as the structural dynamic properties and an important parameter of dynamic response, this chapter examined how to choose the damper, and choosing mainly viscous dampers, introduced a viscous damper to principle and application methods, study the impact of the structural seismic response because of the changes of damping ratio, providing a valuable reference for the further design of the new bridge system.(7) Carried out Flutter stability analysis of potential wind-induced vibrations of large-span self-anchored cable-stayed-suspension bridge in Dalian Port Bay.This paper briefly describes the bridge’s basic theory of the bridge static wind effects and wind-induced vibration, carried out the research with wind resistance through the theoretical analysis to large-span self-anchored suspension bridge, based on the engineering background of Dalian Bay Bridge. Major research:①Carried out flutter stability of self-anchored cable-stayed-suspension bridge of a main span 800m, in multi-mode flutter finite element method, in the main cable long-height ratio, hanging cross-ratio, surface layout of cable surface of cable-stayed bridge, the settings of side cross-supporting bridge piers, and design parameters such as main beam constitution etc. carried out key design parameters affecting the bridge, and discuss rational structure of self-anchored cable-stayed-suspension in the perspective of the wind resistance performance.②The impact resulting flutter can not be ignored in the structural dynamic properties and the effects of non-linear changes of air forces caused by deformation for long-span self-anchored cable-stayed-suspension bridge. Established computing program of flutter analysis of three-dimensional non-linear method for self-anchored cable-stayed-suspension bridge, Based on the structure of deformed state and giving full consideration to non-linear effect of structural deformation. Carried out analysis and research of flutter reliability on self-anchored cable-stayed-suspension in Dalian bay, revealed the extent and mechanism of flutter reliability effect of non-linear effect resulted from structural deformation on long-span self-anchored cable-stayed suspension bridge.(8) The pseudo excitation method is introduced in the structural dynamic reliability analysis, which overcomes the shortcoming of time consuming of the random vibration approach and makes it possible to apply the random vibration approach for large and complex bridge structures. In the paper, the reliability of important structural component, piers and towers used as resist the seismic action, is analysed in detail. It is special considered that the space effect, non-stationary and damping ratio can impact on the dynamic reliability.(9) The system reliability method is established for the self-anchored suspension bridges under ultimate limit states. The globalβ-unzipping method and the different equivalent recursion algorithm are adopted to recognize the significant failure models and equivalent limit state functions. The results show that the globalβ-unzipping method is highly efficient and accurate in recognizing the main failure models of structural system. The bond of failure probability of the self-anchored suspension bridge system is calculated by the Ditlevsen’s theory.更多还原