Affiliation:
1. Kyushu Institute of Technology Fukuoka Japan
Abstract
AbstractThe stress intensity factor (SIF) distribution of a semi‐elliptical surface crack is often used for evaluating the fatigue strength of structures. Virtually exact distributions of SIFs
can be provided along the crack front by solving the hypersingular integral equation of the body force method. In this paper, to create a very accurate SIF variation formula, the elliptical crack SIF solutions
,
,
are used and the SIF ratios
,
,
are mainly focused. Paying attention to the corner point singularity, by applying the least squares method to the ratio
,
in the whole range of parametric angle
,
and
formulas can be proposed. Instead,
formula can be proposed by applying the method of least squares to the ratio of
in the range
but applying directly to
in the range
. In this way, all of formulas proposed in this paper provide the SIFs with better than 1.0% accuracy.