【作者】 刘建兵；

【导师】 蒙云；

【作者基本信息】 重庆交通大学 ， 桥梁与隧道工程， 2011， 硕士

【摘要】 悬索桥的跨越能力大、抗震性能好、轻型美观,已越来越成为特大跨径桥梁的首选桥型。随着时代和经济的发展,交通工具不断推陈出新,汽车载重量增大,速度提高,人们对行车安全、舒适性等都提出了更高的要求。由于悬索桥相对其他桥型还比较年轻,目前悬索桥的维修加固还没有进入一个大规模爆发的时期。但上世纪80年代及之前修建的悬索桥由于当时处于时代的局限性,跨度较小、荷载等级较低,随着车辆荷载及使用时间的增长,都已出现了不同程度的病害;而90年代后悬索桥有了很大的发展,先后修建了一批各具特色的悬索桥,且都处于国家五纵七横交通网的咽喉位置,在交通系统中发挥着极其重要的作用。由于我国超载问题凸显严重,投入运营后短短几年时间内也是病害不断。因此,如何才能经济、快捷、实用的加固好悬索桥提高其承载力具有十分重要的现实意义。由于我国现代悬索桥起步较晚,悬索桥的加固还没有得到足够的重视。本文首先收集、整理了国内的发展状况及使用后的病害情况,提出了悬索桥加固提高承载力的必要性及紧迫性。其次对影响悬索桥的安全因素进行了综合分析,由于国内对于悬索桥的加固研究很少,更没有相关的设计资料,通过对国外悬索桥加固的成功方法进行了总结,得出了修复部分受损主缆、增设辅助主缆、更换悬吊系统、改变加劲梁的结构形式、增加斜拉索形成吊拉组合体系等悬索桥加固方法。本文以具体的工程为背景,利用有限元理论,对原桥进行了结构计算,并根据计算结果结合上述加固方法,对南盘江大桥进行了加固方案比选,提出采用增加斜拉索形成吊拉组合体系加固南盘江大桥的思路。由于新增斜拉索受到原桥客观条件的制约,考虑了多种因素(主梁及主塔的结构形式)对斜拉索锚固区及锚固方式的选择的影响,并对各种锚固方法的使用条件及构造要求进行了对比分析研究,对如何增加斜拉索有了一定的认识。最后对加固后的吊拉组合体系进行了结构计算,并与加固前进行了综合对比,加固后的整体刚度、动力性能及承载力得到了很大的提高,验证了增加斜拉索形成吊拉组合体系加固悬索桥的可行性。更多还原

【Abstract】 The suspension bridge, with its huge span capacity, fine quake-proof ability, and light and artistic features, is becoming the top choice among the huge span bridge. With the development of the times and the economy, the innovation in the transporting vehicle, the increasing of the car load and speed, greater demand has been raised by people to the safety and cozy of traveling. Compared with the other bridge, the suspension bridge is relatively young, so the great maintenance and strengthening to the suspension bridge is still in a relative small scope. However, the suspension bridge built in the 80s or before has some problems in various degree, because the condition in that time is greatly limited, the span and the load capacity is low, and the vehicle load is increasing and the bridge is becoming old. However, great achievement had been got after the 90s, numerous suspension bridge with distinctive features were built at that time. Besides, most of those bridges are located at the key position in the“five vertical and seven horizontal trunk national highways system”, and plays great role in the transporting system. However, as the overloading problem is extremely serious in China, problems are continually arising just few years after coming into service. Thus, great realistic importance is attached to how to strengthen the bridge and improve the load capacity of the suspension bridge economically, rapidly, and practically.As the suspension bridge is still relatively new in China, the attention paid to the importance of the suspension bridge strengthening is not enough. First, this paper collects and sorts out the status of development and the problems rose after being put into service, and then bring out the necessity and urgency of enhancing the load capacity of the suspension bridge. Second, this paper will analyse the factors that affect the safety of the bridge comprehensively. As there is not enough research on the suspension bridge strengthening in China, let alone the relative design material, by summing up the successful method of the strengthening the bridge in foreign countries, this paper will get the conclusion of adopting the method of restoring the damaged main cable, adding assist main cable, altering the hanging system, changing the structural form of the strengthened bridge, adding the suspension cable to form the hanging and stressing assembling and so on.This paper is based on the specific project, and uses the finite element theory to carry out the structural calculation. The relative strengthening method will be brought out according to the calculation results. After selecting the strengthen plan to the Nanpan bridge, this paper will bring out the thought of adding the suspension cable to form the hanging and stressing assembling so that the Nanpan bridge can be strengthened. As the new added cable will be constrained by the former bridge’s objective conditions, and considering the influence of the various factors (main cable and main tower structure form) to the choice of the anchoring manner and suspension anchoring area, and make contrast analyze to the working conditions and structure of various anchoring methods, the knowledge towards the suspension bridge strengthening is greatly enhanced.At last, structure calculation will be carried out toward the strengthened hanging and stressing assembling, and comprehensive contrast will be made to the bridge before strengthened. The general stiffness, dynamic performance, and heavy load ability is greatly enhanced, so that the possibility of strengthening the suspension bridge by adding the hanging and stressing assembling is inspected.更多还原