Study on Elastoplastic Pure Bending Collapse of Cylindrical Tubes

Abstract

In this paper, the elastoplastic bending collapse of cylindrical tube subjected to statically pure bending is studied by using finite element method (FEM). It is revealed in the case of infinite length that the moment of the elastoplastic cylindrical tube is controlled by flattening ratio of tube. Also, it is shown that the flattening ratio of tube can be expressed by axial and circumferential stress as a function of the material and geometrical properties and curvatures. Based on these facts, an approximate numerical method to estimate the maximum moment of cylindrical tubes is proposed, and its validity is shown by comparing with numerical results of FEM.