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

本文对圆柱形钢桥墩屈曲后的延性进行了研究。选择了两种桥墩。一种是普通钢桥墩，另一种是刚性桥墩。选择了两种加载方式。一种是单调弯曲，另一种是循环弯曲。采用试验方法进行了非线性分析，结果表明，钢桥墩在循环弯曲作用下的延性能力明显低于单调弯曲作用下的延性能力，而刚度钢桥墩的延性能力则高于普通钢桥墩。刚性钢桥墩的最大荷载比普通钢桥墩大20%。对阪神Awaji大地震倒塌的钢桥墩进行了非线性分析。计算模型为普通圆柱体和加劲圆柱体截面模型。结果表明，分析得到的桥墩局部屈曲形状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.