Strength evaluation method of a sharply notched structure by a new parameter, 'the equivalent stress intensity factor'

Abstract

A new method is proposed to evaluate the strength of a sharply notched structure with a large notch angle. A new parameter, Ke whch is to be called the equivalent stress intensity factor and which prescribes the singularity of stress distribution near the notch tip, is defined to evaluate the effect of a sharp notch on the fatigue and static strength. This method makes it possible to predict the strength of a notched structure by using the well-known parameters ΔKth and Kic. Fatigue tests of HT60 (600 MPa-class high-strength steel) and SS41 (400 MPa-class mild steel) and a brittle fracture test of an acrylic plate were conducted, and the applicability of the parameter was verified.