Investigation of Effective Parameters on Triangular Cutout Stress in Finite Isotropic Plates

Authors

Abstract

This paper aims at optimizing the parameters involved in stress analysis around a triangular cutout located in a finite isotropic plate under in-plane loading using optimization technique called dragonfly algorithm. In analysis of finite isotropic plate, the effective parameters on stress distribution around triangular cutouts are include cutout bluntness, cutout orientation, plate’s aspect ratio, cutout size and type of loading. The cutout bluntness and cutout orientation are optimizing in various cutout sizes and plate’s aspect ratio, and then the values of each optimum parameter achieved. In this study, with the assumption of plane stress conditions, analytical solution of Muskhelishvili’s complex variable method and conformal mapping is utilized. The plate is considered to be finite, isotropic and linearly elastic. To calculate the stress function of a finite plate with a triangular cutouts, the stress functions in finite plane are determined by superposition of the stress function in infinite plate containing triangular cutouts with stress function in finite plate without any cutout. Using least square boundary collocation method and applying appropriate boundary conditions, unknown coefficients of stress function are obtained. Results show that by selecting the aforementioned optimum parameters, less amounts of stress could be achieved around the cutout leading to an increase in load-bearing capacity of the structure.

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