MULTIPLE CUTOUT OPTIMIZATION IN COMPOSITE PLATES USING EVOLUTIONARY STRUCTURAL OPTIMIZATION

The optimization of cutouts in composite plates was investigated by im plementing a procedure known as Evolutionary Structural Optimization. Perforations were introduced into a finite element mesh of the plate f rom which one or more cutouts of a predetermined size were evolved. In the examples presented, plates were rejected from around each evolvin g cutout based on a predefined rejection criterion. The Limiting ply w ithin each plate element around the cutout was determined based on the Tsai-Hill failure criterion. Finite element plates with values below the product of the average Tsai-Hill number and a rejection criterion were subsequently removed. This process was iterated until a steady st ate was reached and the rejection criterion was then incremented by an evolutionary rate and the above steps repeated until the desired cuto ut area was achieved. Various plates with differing lay-up and loading parameters were investigated to demonstrate the generality and robust ness of this optimization procedure.