【作者】 曹海滨；

【导师】 强士中； 薛继连；

【作者基本信息】 西南交通大学 ， 建筑与土木工程， 2002， 硕士

【摘要】 本文的研究是结合南昆铁路喜旧溪河大桥的施工进行的。喜旧溪河大桥是一座56+88+56m铁路连续刚构桥，其主墩为双肢薄臂高墩，墩高60m；主桥采用悬臂灌注法施工。该桥为在我国最早采用悬臂灌注法修建的大跨度铁路连续刚构桥之一，其结构设计新颖，施工要求高、技术难度大，因此，有必要对其关键施工技术进行系统的总结，以便为同类桥梁的设计与施工提供有益的借鉴。本文本着理论与实践相结合的原则，主要作了以下工作。 1．详细阐述了预应力施工工艺、混凝土施工技术措施、合拢段施工、箱梁0#块施工、自锚式轻型挂篮的设计与应用等悬臂灌注施工的关键施工技术；在工程实践的基础上，对预应力混凝土连续刚构桥悬臂灌注施工中的技术难点进行了较为全面的总结。 2．研究了连续刚构桥悬臂灌注施工的线型控制理论，分析了恒、活载不同时段悬灌混凝土梁段的徐变以及预应力等因素对梁体挠度的影响，在此基础上得出了预拱度的设置计算公式，为线型控制提供了理论基础。 3．喜旧溪河大桥施工中，为了取得良好的施工控制效果，进行了包括预应力束管道摩阻损失、混凝土的收缩和徐变特性等的多项相关试验。通过这些试验，为理论分析提供了更符合实际的计算参数，并且为桥梁的悬臂施工积累了材料，为同类桥梁的施工提供了有益的借鉴。本文对这些试验进行了详细的介绍。 4．结合喜旧溪河大桥施工控制实践，分析了在连续刚构桥梁施工过程中线型和应力控制的具体方法，介绍了线型控制理论在工程实践中的具体实现，给出了理论值与实际值的对比，得出了一定的结论，为类似工程提供了参考依据。更多还原

【Abstract】 This thesis is based on the construction of Xijiuxi River Bridge in the Nanning-Kunming Railway, which is a continuous rigid-frame prestressed concrete bridge with spans of 56+88+56m. The main piers of this bridge are thin-walled high ones, with height of about 60m. Using free cantilever casting construction method to build , this bridge is one of the first long-span continuous rigid-frame PC bridge in China’s railway. With structure in a novel style and high demands on construction, Xijiuxi River Bridge’s technical difficulty is obvious, so many new technologies were employed when it was under construction. In order to offer useful references for similar structures’ design and construction, it is necessary to make a systematic summary of these key techniques adopted by this bridge. Adhering to the principle of combining theory with practice, the major contents are made in this paper as follows.1. Many key construction techniques of continuous rigid-frame PC bridge such as the construction process of prestress, the technological measures of concrete, the construction of part of closure, the construction method of 0# part of the box girder, the design and application of self-anchored light traveling carriage, etc. are thoroughly expounded. Based on the engineering practice, the difficulties in free cantilever casting construction method for continuous rigid-frame PC bridge is comprehensively summarized.2. The geometric control method for free cantilever casting construction of PC girder is studied. Taking into consideration of the influence of dead and living load, the creep displacement of the beam segments casted in different times and prestress on girder’s displacement, the caculating formulas of the adjustment of each beam segments during construction and the technical basis for geometric control is provided.3. In order to achieve good results on construction control of Xijiuxi River Bridge, many experiments such as the piping friction loss of prestress, thecharacteristics of concrete’s contract and creep have been done. A lot of calculating factors which tally with the actual situation much more are supplied by these experiments. A wealth of material for study is accumulated and references for similar project are provided too. These experiments are thoroughly introduced in this paper.4. The practical methods for geometric and stress control during the construction of continuous rigid-frame prestressed concrete bridge are analyzed combining with the project of Xijiuxi River Bridge. The concrete accomplishment of these methods in practice and the comparison between theory and practice are introduced. A lot of conclusions which are valuable have been reached.更多还原