Evaluation of optimal parameters affecting of isotropic plates with polygonal cutout under shear load using particle swarm algorithm

In this paper the optimal values of effective parameters on the stress distribution around polygonal cutouts in isotropic plates are calculated. To achieve this goal, the complex variable method and PSO algorithm have been used. The expansion of the Muskhelishvili’s method are used to analyze the stress distribution in infinite isotropic plates containing various cutouts. By using conformal mapping, the area outside the non-circular cutout is mapped to the area outside of unit circle. The effective parameters on stress distribution around the cutout as design variables include: cutout shape, cutout orientatin and bluntness. The proper selection of these parameters leads to achieve minimum stress around the cutout and result in the load-bearing capacity of structures increases. The goal function in this problem is the maximum stress created around the cutout calculated by the analytical solution method. The results presented in this study shows that by choosing the appropriate shape of cutout and the optimal effective parameters, stress concentration factor can be significantly reduced and lowest stress concentration factor rather than the value of stress concentration corresponding to circular hole can be achieved.