Experimental, analytical, and finite element study of stress concentration factors for composite materials

This article focuses on the evaluation of stress concentration factors for composite materials with varying hole diameters. An innovative method is presented for measuring the stress concentration around a hole using the digital image correlation method. This method can provide a quicker and cheaper testing technique. The digital image correlation method is utilized to evaluate the strain field and the displacement at the edge of the hole and obtain information about fracture mechanisms in the studied materials. The effect of the ratio of the hole diameter to its width (a/w ratio) on both gross and net stress concentration factors around the hole is investigated. In addition, there is a comparison between the net and the gross stress concentration factors uses of the digital image correlation method, the analytical solutions, and the finite-element analysis for both composite and steel materials.