STUDY ON STRENGTH OF STEEL CYLINDRICAL PIPES UNDER CYCLIC BENDING AND AXIAL LOADING.

本文讨论了圆柱钢桥墩屈曲后的延性问题。选择了两种桥墩。一种是普通钢墩，另一种是刚性钢墩。选择了两种加载类型。一种是单调弯曲，另一种是循环弯曲。进行了实验方法和非线性分析。结果表明：循环弯曲下的延性承载力明显低于单调弯曲下的延性承载力，刚性钢墩的延性承载力高于普通钢墩。刚性钢桥墩的最大荷载比普通钢桥墩大20%。对阪神浅路大地震中倒塌的钢桥墩进行了非线性分析。计算模型分为法向圆柱模型和刚度圆柱截面模型。结果表明，分析得到的桥墩局部屈曲形态与试验结果吻合较好。

In this paper ductility of cylindrical steel piers after buckling are discussed. Two kinds of piers are selected. one is normal steel piers and the others is stiffness ones. Two kinds of loading types are selected. One is monotonous bending and the other is cyclic bending. Experimental approach and monlinear analyzes are carried out.The result is that capacity of ductility under cyclic bending is considerable lower than the capacity under monotonous bending and that of stiffness steel piers is higher than that of normal steel piers. Maximum load of stiffness steel piers is larger than that of normal steel piers by 20%.Nonlinear analyzes are carried out for collapse steel piers in Great Hanshin Awaji Earthquake. The calculated models are normal cylindrical and stiffnes cylindrical sectional ones. The results are that the local buckling shapes of analyzed piers are agree with shapes of the experimental results.