径向力作用下弯梁桥横向爬移数值模拟分析

发布时间：2018-06-20 07:02

本文选题：弯梁桥 + 径向力　；参考：《长安大学》2016年硕士论文

【摘要】：由于弯梁桥在投入运营后出现了各种各样的病害,尤其以主梁的横向爬移最为严重。主梁过大的横向位移往往会导致桥梁的支座剪切破坏、墩柱环向开裂等的次生病害。如此,不仅严重影响到了桥梁的使用寿命,还对桥梁的安全运营造成了威胁。因此,对弯梁桥横向爬移的机理进行研究,有效地控制主梁的横向爬移,具有重要的工程应用价值及实践意义。现有研究表明,弯梁桥在运营期间受到的径向力作用是诱发其横向爬移的重要原因,但径向力对主梁横向爬移的作用机理以及径向力作用下主梁的横向爬移规律却没有明确的结论,需作进一步的研究。本文针对径向力作用下弯梁桥的横向爬移问题,借助于有限元软件ANSYS建立空间有限元模型,对主梁的横向爬移情况进行了分析研究。本文主要研究内容如下:(1)通过查阅相关资料,总结前人在弯梁桥横向爬移研究方面的成果以及研究现状,指出径向力作用下弯梁桥横向爬移研究的不足。(2)对ANSYS有限元建模过程中的重要参数及方法进行了讨论,重点围绕支座的模拟、径向力时程的计算展开分析研究,提出了将盆式橡胶支座等效为三个不同刚度的弹簧、板式橡胶支座建立其实体仿真模型的支座模拟方法,并通过算例对其准确性进行了验证,同时也对是否考虑车桥耦合效应时径向力的取值进行了计算分析。(3)采用ANSYS的弹性时程分析,对主梁分别在不考虑车桥耦合效应、考虑车桥耦合效应时主梁的爬移情况进行了一系列的仿真计算,获得了全桥在上述径向力作用下的动力响应,深入分析了主梁关键截面的位移时程曲线、支座反力时程曲线,并对不同情况下主梁的爬移趋势进行对比分析,分别探讨了径向力的大小、车桥耦合效应对主梁横向爬移的影响,总结了主梁在径向力作用下的爬移规律。(4)选取考虑车桥耦合效应时主梁的爬移状态,对主梁在残余位移状态下考虑混凝土的收缩徐变效应时主梁的恢复力进行了计算分析,获取了主梁关键截面处恢复力的变化值,并对计算结果进行比较分析,总结了混凝土收缩徐变对主梁恢复力的影响情况。(5)通过对径向力作用下主梁爬移的数值模拟分析,得到了主梁在径向力作用下的爬移规律,提出了径向力作用下主梁的爬移机理;并对本文的研究进行了展望,对其中尚需改进和进一步研究的问题进行了总结。希望通过本文的研究,能够对弯梁桥的发展有一定的价值和意义,为弯梁桥的安全运营添砖加瓦。
[Abstract]:There are various diseases in the curved girder bridge after it is put into operation, especially the transverse movement of the main beam is the most serious. The transverse displacement of the main beam often leads to the secondary diseases such as the shear failure of the support and the circumferential cracking of the pier column. In this way, not only the service life of the bridge is seriously affected, but also the safe operation of the bridge is threatened. Therefore, it is of great value and practical significance to study the mechanism of lateral movement of curved girder bridge and control the lateral movement of main beam effectively. Existing studies show that the radial force of curved girder bridge during operation is an important reason to induce its lateral movement. However, there is no clear conclusion on the mechanism of radial force acting on the lateral movement of the main beam and the law of lateral movement of the main beam under the action of radial force, which needs to be further studied. Aiming at the lateral creep of curved beam bridge under radial force, this paper establishes a spatial finite element model with the help of finite element software ANSYS, and analyzes and studies the lateral movement of the main beam. The main research contents of this paper are as follows: 1) by referring to relevant data, the paper summarizes the achievements and research status of previous researches on lateral movement of curved girder bridges. It is pointed out that the deficiency of the research on lateral creep of curved beam bridge under radial force is to discuss the important parameters and methods in the finite element modeling process of ANSYS, focusing on the simulation of support and the calculation and analysis of radial force time history. In this paper, the method of simulating the solid simulation model of the spring and plate rubber bearing with three different stiffness is put forward, and the accuracy of the simulation model is verified by an example. At the same time, the radial force is calculated and analyzed when the coupling effect of vehicle and bridge is taken into account. The elastic time history analysis of ANSYS is used, and the coupling effect of vehicle and bridge is not considered separately for the main beam. A series of simulation calculations are carried out on the climbing and moving of the main beam considering the vehicle-bridge coupling effect, and the dynamic response of the whole bridge under the radial force is obtained. The displacement time history curve of the key section of the main beam and the reaction time history curve of the support are analyzed in depth. By comparing and analyzing the movement trend of main beam under different conditions, the influence of radial force and vehicle-bridge coupling effect on lateral movement of main beam is discussed respectively. This paper summarizes the crawling law of main beam under radial force. (4) selecting the climbing state of main beam considering the coupling effect of vehicle and bridge, and calculating and analyzing the restoring force of main beam when considering the shrinkage and creep effect of concrete under the condition of residual displacement. The change value of the restoring force at the key section of the main beam is obtained, and the calculated results are compared and analyzed. The influence of concrete shrinkage and creep on the restoring force of the main beam is summarized. The crawling law of main beam under radial force is obtained, and the mechanism of main beam crawling under radial force is put forward, and the research of this paper is prospected, and the problems that need to be improved and further studied are summarized. It is hoped that the research in this paper will have certain value and significance for the development of curved girder bridge and contribute to the safe operation of the curved beam bridge.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U445.71

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