Multiobjective optimisation of laminated I-beams for maximum crippling, buckling and postbuckling strength

Abstract

The present study deals with the optimal design of uniaxially loaded laminated I-beams for a maximum combination of crippling and buckling load, in the first instance, and a maximum combination of buckling load and postbuckling stiffness, in the second instance. The method of solution involves defining a design index comprising a weighted average of the objective functions and identifying candidate configurations which have to be optimised and compared to determine the best stacking sequence. This multiobjective approach leads to improved crippling, buckling and postbuckling strength. The multiobjective results are compared to single objective results, and the effect of various problem parameters on the optimal designs are numerically studied.