Stress concentration of shoulder fillets in a flat bar under tension and in-plane bending (Effect of protuberances on the stress concentration)

This paper deals with the stress concentration analysis of fillets in an infinite long strip with symmetric rectangular notches or protuberances under tensile load or in-plane bending moment. The stress field induced by a point force in a semi-infinite plate is used as a fundamental solution to solve those problems. The stress concentration factors are systematically calculated under various geometrical conditions. Through the comparison of the present results with the previous research works, it is found that the Peterson's stress concentration charts based on photoelastic tests gives underestimated stress concentration factors by about 10%. The stress concentration factors of a stepped flat bar with fillets are found to be almost determined by the results of shoulder fillets in a semi-infinite plate.