客运专线32m箱梁徐变效应研究

针对已建成通车的武广、沪杭客运专线两种32m跨预应力混凝土箱梁，对比分析施工阶段梁体跨中上拱变形实测数据，探讨箱梁在施工阶段的徐变特性。在此基础上，应用MI-DAs／civil分析软件，采用ACI209R收缩徐变计算模式，根据设计图纸和施工控制要求，建立梁体有限元模型，对比两种箱梁的徐变变形，与实测结果互为验证，预测二恒铺装对梁体变形影响和铺装后期徐变变形。结果表明，沪杭客专32m梁徐变变形较武广客专32m梁小，变形控制措施更为完善。

Study on Creep Effect of 32-span Box Girder in Passenger Dedicated Line

According to 32-metres prestressed concrete box girders applied in passenger dedicated lines of Wuhan-Guangzhou and Shanghai-Hangzhou, a comparative study on measured data of the deformation in upper middle arch during the construction stage is conducted, and the creep properties of the box girder at the con- struction stage is also discussed. By using MIDAS/Civil analysis software, a finite element model based on the design drawings and shrinkage and creep model of ACI209R is established. The theoretical data are compared with the measured data, and proved to be consistent. The impact on girder deformation and long-term creep de- formation caused by the second-permanent pavement is predicted. The results show that, with more adequate de- formation control, the creep deformation of the 32-metres girder of Shanghai-Hangzhou passenger dedicated line is smaller than that of Wuhan-Guangzhou.