预应力连续箱梁桥后期下挠影响因素分析

为了研究预应力混凝土连续箱梁桥后期下挠影响因素，以一典型3跨预应力混凝土连续梁桥为研究对象，采用规范和有限元数值计算结合的方法，分析了箱梁预应力损失和变形的时变效应，在此基础上，进一步分析了边中跨比、合龙顺序和合龙压重等因素对箱梁后期下挠的影响。分析结果表明，预应力混凝土连续箱梁桥的时变效应明显，收缩徐变引起的预应力损失和后期跨中下挠值较大；适当地增加边中跨比有利于减小后期中跨的跨中下挠；合龙时，先边跨后中跨合龙并采取适量的压重，是减小跨中后期下挠的有效手段。

Study on the Influence Factors of Long-term Deflection for Prestressed Concrete Continuous Box-girder Bridge

In order to study the influence factors of long-term deflection of prestressed concrete continuous box girder bridge, the paper analyses the prestress losses and time-dependent effect of box girder by code and the finite element methods on the case of a typical three spans prestressed concrete continuous box girder bridge. Based on the results, the paper analyses the effect of ratio of side to main span, closure process and closure counterweight on the long-term deflection of box girder mid-span. The result...