1987 年 53 巻 488 号 p. 779-785
An influence function method has been developed to analyze stress intensity factors, K, for surface cracks which are subjected to arbitrarily distributed surface stresses. The method has been applied to the analysis of a series of influence coefficients, how easily the K values for a semielliptical surface crack in a round bar can be evaluated against arbitrarily distributed surface stresses. Some examples have been provided to show the effectiveness of the proposed method, including the variation of K due to rotary bending of the round bar, distributions of K in a residual stress field, and those for the cracks existing at the notch root.