Research of Stress Assessment based on Singularity Strength

Hull structure has sharp corners with singularity which tends to produce fatigue cracks and cause structural damages. It's not straightforward to assess FE analysis results of stiffened plating structures because of the stress singularities that are inherent in the overall geometry. This paper concentrates on the analysis of a simple planar right angled cruciform corner and a 135-degree sheet corner through a series of FE analyses using ANSYS. The aim is to try and provide an understanding of the nature of the singularities. Through the understanding a simple method is proposed to estimate the singular stress at the corners using 'as' named as 'singularity strength' which is based on notch-stress intensity factor theory. Finally the estimation methods of 'as' are given for the 2D corners.