A PRACTICAL METHOD TO ESTIMATE THE STRESS-CONCENTRATION OF NOTCHES

Knowledge of stress concentration factor and stress distribution of notches is important to engineers engaged in the design or fracture life assessment of engineering components. In a previous paper, it was pointed out that knowledge of the relevant solutions for stress analysis of cracks may be used to advantage to estimate the stress concentration factor and stress distribution ahead of a notch via the Creager-Paris stress field solution for notches. It was shown that this method accurately predicted the stress concentration factors and notch-tip stress distribution in a number of double- and single-edge-notched plates. Finite-element stress analysis results for plates with multiple notches are recently available. Stress concentration factors for a variety of notch configurations have also been collected from relevant handbooks. In the current work, a comparison was made between the finite element results and handbook solutions with estimates from fracture mechanics data, and reasonable agreement was found. A number of approximate expressions have been proposed to estimate notch-tip stress distributions. These estimates were also compared with finite element results, and a guideline is suggested for the choice of approximate expressions to ensure maximum accuracy.