钢管混凝土拱桥收缩次内力计算

针对管内混凝土收缩会在钢管混凝土超静定拱中产生次内力，根据钢管混凝土拱的结构特性，提出了2种钢管混凝土拱收缩次内力计算方法——解析法和有限元法，并采用这2种计算方法对9个钢管混凝土拱桥实例进行分析。结果表明：2种方法均可用于计算钢管混凝土拱桥的收缩次内力，但采用等效降温15℃～20℃的解析法计算得到的收缩次内力较采用有限元法直接计算的收缩次内力大了50％以上；若采用等效降温的解析法计算，等效降温值还有待于进一步研究。

Calculation of Shrinkage Secondary Internal Force of CFST Arch Bridge

Aimed at the shrinkage of core concrete causing secondary internal force in the concretefilled steel tubular （CFST） fixed arch, according to the structural properties of CFST arch, two methods were proposed to calculate the shrinkage secondary internal force, including analytical method and finite element method. The two methods were used to calculate the shrinkage secondary internal force of nine CFST arch bridges. The results show that both the two methods can be used to calculate the shrinkage secondary internal force of CFST arch bridge. But the results from the equivalent decreasing temperature of 15℃-20 ℃in analytical method are larger more 50%0 than the results calculated directly from the finite element method. If the analytical method of equivalent decreasing temperature will be used, the equivalent decreasing temperature values maybe research in the future.