Prediction of Bending Collapse Behaviours of Thin-Walled Open Section Beams

摘要

Crushing behaviours of thin-walled open section beams are simulated using the simplified kinematic models. Systematic process of simulation is presented and applied to L-section and I-section beams. Basic processes can be conceptually divided into composition of mode shapes, location of deforming elements as a function of global process control parameter, calculation of plastic work done, estimation of mode parameters and calculation of crushing behaviours. A systematic numerical method is suggested to determine geometry and mode parameters according to the progress of collapse since it is generally very complicated to obtain closed form expressions for bending collapse problems. In the present method, mode parameters are determined by minimizing the plastic work done at very early stage of collapse, while it has been done conventionally by minimizing the mean crushing force. The results are in good agreement with those from finite element analyses and from the literature.