先简支后连续桥梁毕业设计.doc

先简支后连续桥梁高速公路的迅速发展使得桥梁的数量大幅度增加，而高速度的行车则要求桥梁具有较好的连续性能、较少的伸缩缝构造等。在高等级公路桥梁中，多孔中等跨径的桥梁占很大的比重，桥面连续的简支梁结构体系由于存在桥面容易开裂等缺点而在与连续梁结构体系的竞争中常常处于下风。但是由于现浇连续梁的施工复杂繁琐，人们一直希望将简支梁的批量预制生产和连续梁的优越性能结合起来，用梁或板批量预制生产的方式来加快连续梁的建设速度，以省去繁琐的支模工序，由此产生了将整跨梁板预制、架设就位后在端部浇筑混凝土并张拉预应力使之连续的“先简支后连续”施工法，而形成的体系则被称为“先简支后连续结构体系”。 随着先简支后连续桥梁结构应用的日益增多，许多问题也随之而来，其中最突出的是接头方式的问题。连接段的接头形式是简支转连续桥梁结构的关键，它决定了桥梁结构的造价，施工的难易程度及以后的使用性能，合理的接头形式可收到明显的经济效益。 本文在借鉴国内外目前的后连续工艺和体外预应力理论的基础上，提出了应用体外预应力进行后连续的新型施工工艺。并通过大型有限元软件ANSYS建立试验梁的有限元模型，对试验梁进行了全过程的非线性模拟，并进行了试验验证。对实验室T型试验梁从设计、制作到加载试验及数据结果进行了具体的论述。并综合了数值模拟结果和试验梁的数据结果进行了对比分析，对试验梁的裂缝行为、挠度变化、弯矩重分布以及连续梁的极限承载力进行了较为深入的研究。 关键词 先简支后连续结构体系；体外预应力；非线性；极限承载力； 应力增量 Abstract With the development and construction of freeways, large amount of bridges are being built. High-speed driving demands good continuity and less expansion joints of the bridges. Those of multi-span, middle-length are of large percentage among advanced bridges. Simply-supported girder bridges with continuous decks are inferior to those of continuous girders because their decks crack easily. Owing to the complex construction of continuous girder bridges, which is laboursome and time-consuming, people have been thinking about an approach to combining the advantages of the two so as to speed up the building and reduce the work procedures. Thus the “simply-supported-continuous system” is introduced. With the popularization of such practice, many problems have been found. The style of continuous ends is the most prominent problem. The style of continuous ends is one of the key problems of the simply-supported-continuous system. The Engineering Cost of Bridge Structure, The difficult degree of Construction and the performance of application is determined by its style. For the rational joint structure can bring about tangible results. This dissertation use the current correlative techniques and research harvest，and an application of External Prestressing for connecting the continuous ends with the simply-supported and con