钢箱梁斜拉桥顶推施工关键问题研究-桥梁与隧道工程专业论文.docxVIP

摘要摘要 摘要 摘要 顶推施工方法在预应力混凝土连续梁桥的施工中早有应用，这类桥梁的设 计方法和顶推施工工艺目前都已经相对比较成熟。而钢箱梁顶推施工近期应用 日益广泛，但是理论研究却滞后于工程设计实际，因此，本文选择钢箱梁斜拉 桥顶推旎工的关键问题进行分析，为同类桥梁的设计和施工提供参考。 本文从整体受力、局部受力、局部稳定三个方面考虑钢箱梁顶推过程中可 能出现的问题，建立解析模型分析导梁设计对主梁内力以及支点反力的影响， 并以解析模型的分析结论为基础，结合有效宽度分布理论，提出了顶推梁整体 受力的简化计算方法。在解析分析的基础上，利用有限元方法对局部受力和局 部稳定进行了分析，讨论纵隔厚度、底板厚度、支承面积等参数对局部受力的 影响，．并对局部构造与局部稳定的影响关系进行分析，为截面设计和施工方案 设计提供依据。 采用顶推施工的桥梁的设计流程一般是设计、施工分别考虑，对不能满足 施工要求的局部进行补强。这样将设计施工分离考虑，不能充分体现顶推施工 对截面．设计的影响，易造成施工成本的增加。本文尝试考虑截面优化设计问题， 提出了利用拓扑优化的方法进行截面的初步设计，并根据这一思路探讨了采用 顶推施工的钢箱梁斜拉桥的合理截面形式，为同类桥梁的设计提供参考。 关键词：顶推、钢箱梁斜拉桥、局部构造、合理截面 AbstractABSTRACT Abstract ABSTRACT The method of incrcmenml launching is widely used in the construction of prestressed concrete continuous bridges,and has made considerable progresses in recent years．However,the utilization of ineremenml launching in steel box girder has outpaced its theory research．In this paper,some key problems of applying incrcmenml launching in cable-stayed bridge with steel box girder are studied and discussed，for the design and construction ofbridges alike． The paper exploited some key problems such as internal force，local stress and local stability in incremental launching，We proposed a analytical model which focnses on the internal force to analyze bow nose girders affects the stress of main girder and reaction of supports．Then,we integrate the conclusion of analytical model with the effective width distribution theory,and give a simple calculation method of internal force for incremental launched bridge。Based on the analysis above，the finite elemem method is used to analyze local stress and local stability．as well鹊the effect of some parameters to local stability,which will supports the design ofsection structure and constructing project． Generally,the design and construction are considered separately in the process of bridge girder designing using the incremental launching construction method,and local constructional detail below construction standard Call be reinforced．However,separate co