Evolutionary thickness design with stiffness maximization and stress minimization criteria

A shape or topology design with the sti3ness maximized and the maximum stress minimized is usually of practical signi=cance in structural optimization. This paper proposes a thickness based evolutionary procedure for such multicriteria design problems. To make the multicriteria optimization suit to more realistic structural situations, multiple maximum stress locations and multiple load cases are taken into account in this paper. To balance the sti3ness and stress criteria, a weighting average scheme is adopted to identify the overall e3ects on the two components of design objective due to varying an element’s thickness. Adopting the proposed optimization procedure, a design with maximized static sti3ness and minimized peak stress is achieved by gradually shifting material from the under-utilized regions onto the over-utilized ones. The examples show the capabilities of the proposed method for solving multicriteria sizeand topology designs for both singleand multipleload cases