混凝土连续弯梁桥横向爬移模型研究

发布时间：2018-02-26 10:31

本文关键词： 连续弯梁桥横向爬移支座摩阻力汽车离心力模型研究　出处：《长安大学》2015年硕士论文　论文类型：学位论文

【摘要】：混凝土连续弯梁桥以其优美而顺滑的曲线线形、对地形障碍较好的跨越能力、对路线整体规划的完美连接等特点,在工程实际中得到了广泛的应用。混凝土连续弯梁桥竣工运营后,较为常见的病害主要是主梁横向爬移,病害情况较严重时,还会发生主梁向曲线外侧横向移动,导致伸缩缝和支座剪切破坏、抗震挡块被推翻、墩柱受弯开裂等次生病害。加之后期运营条件恶化,倾覆危险增加。在桥梁通行能力快速增长以及桥梁使用寿命大大加长的背景下,如何使得桥梁在使用寿命期内的侧向位移病害得到有效的控制,进而确保桥梁在使用寿命期内,能安全的负担起承受荷载的任务,成了当今急需解决的问题。而开展此方面的研究,对于今后混凝土连续弯梁桥在运营中的横向爬移问题的防治具有很好的指导意义。本文针对混凝土连续弯梁桥普遍存在的横向爬移病害,结合笔者近年来所接触的多个混凝土弯梁桥的检测加固与养护维修项目,对影响混凝土连续弯梁桥横向爬移的诸多影响因素进行研究,通过分析得出了汽车荷载作用下的离心力是混凝土连续弯梁桥发生横向爬移病害的主要原因。通过经典力学的分析过程,以及汽车离心力的特点,结合有限元模型的计算结果,得出混凝土连续弯梁桥横向爬移的机理,即梁体在汽车离心力的作用下产生振动,引起支座摩阻力发生变化,当支座摩阻力增大到一定程度时,主梁梁体发生横向位移。汽车荷载撤去之后,梁体会发生一部分弹性变形恢复,但仍有一小部分无法恢复。后期随着汽车荷载的长期作用以及桥梁整体的收缩及徐变作用影响,会使桥梁的横向爬移趋势越来越明显。一旦支座摩阻力的大小超过临界值,主梁梁体便会发生大体量的横向爬移。在得出上述结论之后,本文还考虑到各项影响因素的综合作用,对所建立的计算模型进行进一步的优化,使得模型更能准确的代表实际情况。通过对混凝土连续弯梁桥横向爬移现象的机理研究,为以后的同类病害提出预防和处治措施。
[Abstract]:The continuous curved concrete beam bridge is characterized by its graceful and smooth curve line, better crossing ability to the terrain obstacle, perfect connection to the whole route planning, etc. It is widely used in engineering practice. After the completion and operation of the concrete continuous curved beam bridge, the common diseases are mainly the lateral movement of the main beam, and when the disease is serious, the main beam will move laterally to the outside of the curve. Secondary diseases such as shearing failure of expansion joints and supports, overthrowing of seismic blocks, bending and cracking of piers, and deterioration of later operating conditions, Under the background of the rapid increase of bridge capacity and the long service life of bridge, how to effectively control the lateral displacement disease in the service life of the bridge, and then ensure the bridge in the service life period, To be able to safely bear the burden of loading has become a problem that needs to be solved today. And research in this area has been carried out. It is of great significance to prevent and cure the lateral creep of concrete continuous curved beam bridge in the future. This paper aims at the common disease of lateral climbing of concrete continuous curved beam bridge. Combined with the inspection, reinforcement and maintenance of several concrete curved beam bridges in recent years, the factors that affect the lateral movement of concrete continuous curved beam bridges are studied. It is concluded that the centrifugal force under automobile load is the main cause of lateral creep of concrete continuous curved beam bridge. Through the analysis of classical mechanics and the characteristics of automobile centrifugal force, the calculation results of finite element model are combined. The mechanism of lateral movement of concrete continuous curved beam bridge is obtained, that is, the beam body vibrates under the action of automobile centrifugal force, which results in the change of support friction, and when the support friction increases to a certain extent, Transverse displacement occurs in the main girder beam. After the vehicle load is removed, the beam experiences partial elastic deformation recovery, but there is still a small part that can not be recovered. At the later stage, with the long-term effect of the vehicle load and the effect of the shrinkage and creep of the bridge as a whole, It will make the lateral movement of bridge more and more obvious. Once the friction resistance of the support exceeds the critical value, the beam body of the main beam will move laterally in large quantities. In this paper, considering the comprehensive effect of various factors, the calculation model is further optimized to make the model more accurate to represent the actual situation. Through the study of the mechanism of lateral movement of concrete continuous curved beam bridge, To put forward prevention and treatment measures for similar diseases in the future.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U445.7

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