抄録
This paper is concerned with the elastic-plastic analysis of an infinite plate with an elliptic hole. The method of analysis is the body force method extended to the elastic-plastic problems. In this method the solutions are obtained by superposing the stress fields of a pair of point forces in an infinite plate with an elliptic hole so as to satisfy the constitutive equation. The main results obtained are as follows : (1) If the notch root radii ρ and the maximum elastic stresses σe<max> =Ktσ∞ (Kt : stress concentration factor, σ∞ : stress at infinity) in several notches are equal respectively, the projected lengths of the plastic zone are nearly the same. (2) When σe<max>/ σs =1.3-2.0 ( σs : yield stress), the ratio of the projected length of plastic zone under plane strain condition to that under plane stress condition is about 0.5. (3) The elastic-plastic stress and strain at the bottom of a notch are almost determined by the maximum elastic stress σe<max> alone.
