Stresses Around a Rib-Reinforced Elliptic Hole in a Circular Cylindrical Shell Under Tension

The stress state around a rib reinforced elliptic hole in a circular cylindrical shell under axial tension at its ends is determined by perturbation in terms of a curvature parameter and the eccentricity of the elliptic hole. The reinforcing rib is assumed to be rectangular in cross section, and has extensional, flexural and torsional rigidities. Nondimensional membrane stresses and bending stresses around the hole are given for different values of E₁/E₁ where E₁ and E are moduli of elasticity of the rib and the shell respectively. It is shown that the reinforcing rib substantially reduces the stress concentration around the hole.