大朗特大桥加固研究

【作者】 李刚；

【导师】 郭向荣； 钟勇兵；

【作者基本信息】 中南大学 ， 建筑与土木工程， 2010， 硕士

【摘要】 随着重载列车的开行和列车速度的提高,很多既有线路上桥梁刚度不足的问题逐渐显现出来,严重影响了行车安全,因此给新建铁路桥梁的设计和既有线桥梁的加固提出了更高的要求。预应力混凝土T形梁具有结构简单、受力明确、节省材料、架设安装方便、工厂化预制、工期短、造价低等优点,因此被广泛应用于桥梁建设中,特别是跨度16m、32m简支T形梁占有相当高的比例。如何有效的对既有线T梁桥进行加固并从理论和实践加以分析论证成为目前桥梁加固的重要课题之一。本文以大朗特大桥为背景,对T型梁桥的加固前后力学性能行进分析检测,得出其加固效果,为类似T桥梁加固具有借鉴意义。全文完成了以下主要工作：(1)以大朗特大桥为工程背景,分析了目前我国桥梁面临的主要问题,简要介绍桥梁加固在国内外的发展概况,阐明了桥梁加固对改进既有线运营状况的重要意义。(2)简述了大朗特大桥加固前的桥梁概况,并对其进行检测分析,得出桥梁的病害缺陷情况。(3)针对大朗特大桥的病害情况,结合现有加固技术,提出具体的加固方案。(4)对大朗特大桥的加固工艺进行简单的介绍。(5)对大朗特大桥加固效果进行分析检测并作出评价,以对类似的桥梁加固提出行之有效的方法和建议。(6)建立大朗特大桥加固前后的空间有限元模型,从理论上对加固前后桥梁进行自振特性和桥梁横向、竖向刚度进行了分析比较。更多还原

【Abstract】 With the appearance and the increasing speed of the heavy haul trains, the problem that they are lack of stiffness in the existed lines emerges gradually, which affect the safety of traveling seriously. Thus the design of bridge in the newly-built railroad and the consolidation of existed lines are required higher demands. The simple supported T-shape prestressed concrete beam embodies numerous merits that having a sim-ple structure, bearing stress definitely, saving materials, being expediently fixed and prefabricated, having a short construction time limit and a low cost, so on and so forth. Thanks to the good qualities mentioned above, it applied widely in building bridges, especially the T-shape beam of 16m and 32m. so how to reinforce the existing T-shape bridge effectively and carry out analysis and demonstration on them theoretically and practically become an important issue for bridge strengthening.In this paper, taking the DaLang bridge as an example, by the analysis and measurement of mechanical properties on pre and post reinforcement of T-Beam Bridge, the reinforcement result is carried out which provide some reference significance to similar project. The main contents in this thesis are as the following:(1) Taking the DaLang bridge as an example, main problems of our country bridge is analyzeda, the development situation of bridge inforce-ment in china and abroad is briefly introduced and the important significance of inforcement to improve existing lines is elucidated.(2) The overview of DaLang bridge before consolidation is descripte-d briefly and test it to get disease and defects.(3) Forced on the disease and combined with the presenting strength-ening technology, the specific reinforcement plan is put forwarded.(4) The strengthening technology of DaLang bridge is simplely introducted.(5) The reinforcement effect is tested and evaluated to give some reference significance to similar project.(6) The finite element model of pre and post reinforcement of DaLang bridge is established to analyze and compare on the natural vibration characteristics and lateral stiffness and vertical stiffness theoret-ically.更多还原