【作者】 李路；

【导师】 李乔；

【作者基本信息】 西南交通大学 ， 桥梁与隧道工程， 2012， 硕士

【摘要】 近年来随着大跨度桥梁尤其是斜拉桥的飞速发展,传统的伸缩装置由于其自身的局限性已经无法满足桥梁发展的需要,因此寻找新的伸缩结构就显得尤为必要。在这种形势下,一些专家学者将机械中活塞的运行模式,引入到土木工程中并以此提出以铰代缝的思想,而刚性铰的出现正是这种思想的结晶。虽说刚性铰已经开始在大跨度桥梁中使用,然而对它的研究却还处于初级阶段,本文主要对其在静力荷载作用下对桥梁的贡献,以及作为一种承力构件,在荷载作用下它的力学性能进行研究。本文以有限单元单元法为理论依托,借助BSAS、ANSYS等有限元软件对刚性铰在正常运营阶段,对全桥主梁及索塔的影响进行模拟分析,以确定作为一种新型伸缩装置在正常运营阶段对全桥的作用。然后在整体分析的基础上对刚性铰局部进行分析,以确定在正常运营阶段,刚性铰各组成部分的应力情况,以及在正反弯矩作用下,小箱梁内支座是否存在与箱梁出现脱离和虚接的现象。本文通过对全桥的模拟分析得出,正常运营阶段在不考虑温度荷载的情况下刚性铰的存在与否对主梁及索塔的应力分布及应力水平几乎没有影响；当考虑温度荷载影响时,刚性铰的存在能够很好的释放主梁由于温度变化引起的变形,从而能够减小温度变化对主梁及索塔应力的影响。对刚性铰局部进行研究结果表明在荷载作用下,组成刚性铰的小箱梁也能很好的承受外荷载的作用,而且应力水平在正常范围内；在正反弯矩作用下,箱梁内部分支座出现与小箱梁虚接的现象。总之,刚性铰作为一种伸缩装置具有强大的变形能力,能够释放大跨度桥梁由于温度变化引起的巨大的位移,消除了由于温度变化导致结构应力较大引发的安全隐患；同时,作为一种承力结构它又能够很好的承担外荷载的作用。更多还原

【Abstract】 With the fast development of the long-span bridge especially the cable-stayed bridge in recent years, the traditional expansion joint can no longer meet the needs of the bridge development due to its own limitations. Therefore, it is essential to find a new expansion structure. Under this circumstance, some experts and scholars have applied the operational mode of piston in mechanics to civil engineering and thus put forth the thought of hinge joint, resulting in the emergence of the rigid hinge. Although the rigid hinge has already been used in the construction of the long-span bridge, the research about it is still at the fundamental stage. This thesis is intended to analyze the contribution of the rigid hinge to the bridge construction as well as its mechanical properties as a component able to withstand the force under the effect of static load.Based on the theory of Finite Element Method and aided by the FEM software such as BSAS, ANSYS etc.the thesis tries to give a holistic analysis of the influence of the rigid hinge on the bridge girder and the cable support tower under the normal operation so as to certify its significant function as a new expansion joint in the bridge construction under the normal operation.Then the thesis has a partial analysis of the rigid hinge on the basis of holistic analysis to assure the stress condition of each rigid hinge component under normal operation and also has an analysis of whether the supports of the small box girder would be detached from and virtually connected with the box girder.From the model analysis of a whole bridge in this thesis, it can be concluded that without regard to the temperature load under the normal operation, the existence of the rigid hinge has little influence on the stress distribution and stress level of the main girder and cable support tower and with regard to the temperature load, the existence of the rigid hinge is able to sustain the distortion of the main girder as a result of the temperature changes so as to make the stress of the main girder and cable support tower as small as possible by the temperature changes. In the study of the parts of the rigid hinge, it is found that under the load effect the small box composed of rigid hinges is able to withstand the external load well and its stress level is in normal function and under the effect of positive and negative flexural moment the some support saddles in the box girder will become virtually connected with the small box girder.In conclusion, the rigid hinge, as a expansion joint, has strong deformation ability and is able to sustain the huge displacement of the long-span bridge caused by the temperature changes so that it eliminates the potential risks resulting from the large stress the structure has to withstand as a result of the temperature changes. Meanwhile, the rigid hinge is also able to bear the effect of external load as a load-carrying structure.更多还原