尼尔森体系钢管混凝土系杆拱桥拱助稳定性及系梁横向受力研究

发布时间：2018-03-13 18:05

本文选题：钢管砼拱桥　切入点：尼尔森体系　出处：《兰州交通大学》2017年硕士论文　论文类型：学位论文

【摘要】：普通的钢管砼拱桥在国内外已有较长的发展历史,且应用广范,在桥梁建设中发挥了不可替代的重要作用,近年来,我国引进了尼尔森体系系杆拱桥,该种拱桥的主要特征为用斜向的吊索代替了传统的竖向吊索,这必将带动拱桥新的发展,但随着当下桥梁跨度的增大,桥面变的更宽,拱桥稳定性的问题和系梁横向力学特性的问题日益凸显,关于尼尔森体系系杆拱桥拱肋稳定性的相关研究还非常少,关于尼尔森体系系杆拱桥系梁的横向力学特性分析更是存在较多的不确定性。本文针对尼尔森体系系杆拱桥的稳定性和系梁横向力学特性深入研究,得出相关结论可为工程建设提供有力的参考。本文首先参考了大量国内外桥梁方面文献,介绍了国内外在尼尔森体系的系杆拱桥方面的发展历史及研究现状,以及本文的选题意义和主要研究工作。国内外目前尚未见到其统一的规范和规程(关于钢管混凝土拱桥的设计与施工),这就导致目前国内外的设计与施工中存在较大自由行,难以严格把控其合理性,而本文研究的尼尔森体系系杆拱桥作为一种新型的系杆拱结构形式,更是没有统一的设计施工标准,在这种情况下,盲目的凭借以往的拱桥经验进行设计和施工,不合理的设计和盲目的施工可能导致工程的病害甚至坍塌等事故。因此目前对尼尔森体系系杆拱桥的钢管混凝土拱桥的静、动力性能进行研究急需开展,以便为其合理的设计和施工提供可靠的理论基础。作为全球的基建大国,我国已经有非常多的普通钢管混凝土拱桥的相关经验,为系杆拱桥在我国的快速发展奠定了重要基础,但尼尔森体系系杆拱桥的相关经验还少之又少,国外已经对其有了丰富的应用和发展,且研究比较成熟,相比之下,国内学者即使对普通钢管混凝土拱桥的研究也正方兴未艾,而对钢管混凝土拱的尼尔森体系系杆拱桥的研究还鲜有开展。其次,研究稳定性相关的理论。在拱桥设计中,失稳问题不容忽视,研究拱的失稳有重要意义。从失稳的理论层面对稳定性问题进行了详细的研究,主要包括了第一类稳定的问题的有限元分析和其非线性状态的近似求解方法,以及第一类失稳中的面内失稳和面外失稳的研究理论和有限元求解方法。在理论分析的基础上,结合本文的实际工程,研究了尼尔森体系系杆拱桥的拱肋的稳定性及其影响因素,利用有限元软件MIDAS建立了杆系结构有限元模型,对比分析4种荷载工况、5种横撑形式、变化的横撑刚度及变化的预应力对拱肋稳定性的影响,并得出结论:在研究荷载对拱肋稳定性影响中可以看到横向风荷载对拱肋稳定性影响较小,而系梁上增加竖向荷载,拱肋的稳定性有显著的降低,因此可以看出在吊索传递更多的荷载给拱肋时,其稳定性随之降低;拱肋间横撑形式对拱肋稳定性有明显的影响,对比分析可以看到中间米撑两侧各两组K撑的横撑形式是即经济又有效的横撑形式;横撑刚度提高也使得拱肋结构整体稳定性随之提高,但随着横撑刚度进一步提高对拱肋整体稳定的提高有限,且两边横撑刚度的变化对结构稳定系数有较大影响,基于有限元分析结果,建议中间横撑的刚度减低为原设计的0.6倍,边横撑维持不变,这样整体稳定性仅降低了1.16%,可以在几乎不降低结构稳定性的基础上变的更经济;预应力的施加和增大均使拱肋稳定系数提高,从增加量上分析,预应力荷载施加基数从0.2增加至1.8,稳定系数从12.10增加到12.54,增加了3.64%,可见预应力对拱肋稳定性影响较小。再次,对于箱形梁桥的横向内力分析方法进行了探讨,探讨了包括国内外学者对于箱梁横向分析的主要方法如平面框架法、板单元影响面法等。基于前述基本理论,结合本文实际工程:郑万128m尼尔森体系系杆拱桥,石梁河特大桥,对于该桥的箱室截面及其横梁进行了精细化多方案有限元分析,分别建立全桥有限元模型、平面杆系系梁截面、横梁截面、有横梁的板单元系梁模型、无横梁的板单元模型及利用ANSYS建立简化的节段实体有限元模型,通过与全桥实体模型对比分析尼尔森体系系杆拱桥的系梁横向力学特性。分析得出了箱室的平面框架法仅可适用于无横隔板或横隔板纵向距离很大的箱梁、对于有横隔板的箱梁利用板单元计算更为准确且操作方便等主要结论。认为在边腹板、边室跨中、中腹板及中室跨中具有一个应力的峰值点,设计值应作为最不利点,在计算中平面框架法对有横梁的拱桥系梁并不适用,在箱室处计算值偏大,在横梁处计算值偏小,这是由于系梁纵向荷载分布不均匀导致的,横梁处刚度较大则承受了更大的荷载,而箱室处刚度较小则承受了较小的荷载。最后,对本文全部内容给出结论,本文阅读了大量相关文献,对涉及尼尔森体系系杆拱桥稳定性相关理论和系梁横向分析方法进行了总结,本文依据实际工程石梁河特大桥,针对尼尔森体系系杆拱桥的稳定性和系梁横向力学特性进行了初步探讨,得出了有益的结论。下承式尼尔森体系系杆拱桥结构形式新颖,成桥后造型美观,观赏性强。受力方面,能承受较大的超载和偏载;钢管砼拱桥在国内外已有较长的发展历史,且应用广范,奠定了坚实的理论和施工基础,尼尔森体系系杆拱桥的引进必将带动拱桥的新的发展。随着国内外诸多学者对斜向吊索的系杆拱桥的研究不断深入和不断的积累建设经验,尼尔森体系桥梁将作为重要的结构形式应用在桥梁建设中。
[Abstract]:The history of the development of ordinary concrete filled steel tubular arch bridge at home and abroad have been long, and wide range of applications, in the bridge construction has played an important role, which can not be replaced in recent years, China has introduced a system of Nelson tied arch bridge, the main feature of this kind of arch bridge with inclined hangers instead of the traditional vertical sling, the arch bridge will drive the new development, but with the increase of the span of the bridge deck, wider, transverse mechanical problems and beam characteristics of the arch bridge stability problems have become increasingly prominent, there is very little research on the stability of the Nelson system of arch rib tied arch bridge, the transverse mechanical characteristics analysis of Nelson system tied beams there is more uncertainty. This paper studies the stability and mechanical properties of deep beams for Nelson tied arch bridge system, draw relevant conclusions and provide for the construction of the project Reference. Firstly, according to the domestic and international bridge literature, introduces the Nelson system at home and abroad in terms of Arch Bridge Development and the research situation and the significance of this topic and the main research work at home and abroad. It has not been seen the unified norms and regulations (the design and construction of CFST arch bridge), the led to the current design and construction at home and abroad are quite free, it is difficult to strictly control its rationality, and Nelson tied arch bridge system research as a new form of tied arch structure, it is not the design and construction of a unified standard, in this case, the blind with previous design and experience of arch bridge the construction project may lead to disease or even collapse accidents such as unreasonable design and construction of the blind. So Nelson Guan Hunning steel tied arch bridge system Soil arch bridge static, dynamic performance research is urgently needed, so as to provide a reliable theoretical basis for the reasonable design and construction. As a global power infrastructure, there has been a lot of ordinary concrete filled steel tube arch bridge experience in China, for the tied arch bridge has laid an important foundation in China's rapid development, but the relevant experience Nelson tied arch bridge system is less and less, foreign countries have on the application and development of the rich, and the research is relatively mature, by contrast, domestic scholars even on ordinary concrete filled steel tube arch bridge is the ascendant, and the study of Nelson system of tied arch bridge of CFST arch bridge is rarely carried out. Second study on the theory, related to the stability of arch bridge. In the design, the instability problem can not be ignored, the research of arch instability has important significance. From the theoretical level of instability of face stability problems in detail The study mainly includes the approximate solution of the finite element method first stability problem analysis and the nonlinear state, and the first instability and instability in the in-plane buckling theory and finite element method. On the basis of theoretical analysis, this paper combined with practical engineering, research the arch rib stability factors and influence of Nelson system of tied arch bridge, a member structure finite element model using the finite element software MIDAS, comparative analysis of 4 kinds of load conditions, 5 kinds of cross brace form, the influence of the change of the brace stiffness and change of prestressed arch rib stability, and draw the conclusion: in the study of load the arch rib stability influence can be seen in the lateral wind load of arch rib has little effect and stability, beam on vertical load increasing, the stability of arch rib is significantly reduced, it can be seen that the load transfer more in a sling To the arch rib, the stability decreases; the transverse brace between the arch form has obvious influence on the stability of the arch rib, a comparative analysis can be seen on both sides of the two meter intermediate support group K brace brace form is an economical and effective cross brace form; cross brace stiffness increase also makes the whole stability of arch structure but with the increase of transverse brace stiffness of arch rib and further improve the overall stability and improve, on both sides of brace stiffness changes have great influence on the structure stability coefficient, finite element analysis results based on the proposed intermediate cross brace stiffness is reduced to 0.6 times of the original design, the side brace remains unchanged, so the overall stability decreased only 1.16%, can be almost does not reduce the structural stability become more economical; and the increase of the applied prestressed arch rib stability coefficient increased, from the analysis of quantity increase, prestressed load base increased from 0.2 to 1.8, The stability coefficient increased from 12.10 to 12.54, an increase of 3.64%, visible on arch rib stability of prestressed is less affected. Again, the transverse internal force of box girder bridge analysis methods are discussed, including domestic and foreign scholars discussed the transverse analysis of box girder main methods such as plane frame method, plate element method. The influence of surface based on the basic theory, combined with the actual project: Zheng Wan 128M Nelson system tied arch bridge, stone river bridge, the bridge section of the chamber and the beam of the fine finite element analysis program, established the whole bridge finite element model of plane frame beam cross section, the cross section of the beam, a beam plate element system the beam model, beam and plate element model established by ANSYS simplified segment finite element model, the beam transverse mechanical properties compared with the solid model of the whole bridge analysis system of arch bridge, Nelson . analysis of the plane frame method can only be applied to the chamber without diaphragm or diaphragm vertical distance large box girder for diaphragm box girder using plate element calculation is more accurate and convenient operation. The main conclusion that at the edge of web side across the room, in the room across the web and with a stress peak point, design value should be as the most unfavorable point in the calculation method of plane frame tied arch bridge beams the beam does not apply, the calculated value is larger in the box office, the calculation value is small in the beam, this is because of the beam longitudinal load due to the uneven distribution. The beam stiffness is larger under higher loads, while the smaller chamber stiffness is under small load. Finally, contents of this paper are concluded in this paper, reading a lot of literatures, the transverse stability analysis system relates to the related theory and Nelson tied arch bridge beam Methods are summarized, according to actual engineering Shiliang River Bridge, the transverse mechanical stability and beam characteristics of Nelson tied arch bridge system were discussed, some useful conclusions are obtained. Through Nelson system tied arch bridge structure is novel, beautiful shape, highly ornamental. The force, can under high overload and unbalanced load; the development history of steel pipe concrete arch bridge at home and abroad have been long, and wide application range, and lays a theoretical foundation of the system construction, Nelson tied arch bridge arch bridge will be driven by the introduction of new development. With many scholars at home and abroad in the study of oblique arch bridge sling deepening with the continuous accumulation of experience in the construction of the bridge, Nelson will serve as an important form of system structure used in the bridge construction.

【学位授予单位】：兰州交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U441

【参考文献】