Abstract
This paper presents a practical equation to calculate the mode I stress intensity factor for an inner surface circumferential crack in a finite length cylinder subjected to axisymmetric and quartic distributed stress on the crack surface. The equation was derived by applying the authors' weight function for the crack. The equation is valid for wide ranges of mean radius to wall thickness ratio, Rm/W≥1, and of relative crack depth, a/W≤0.5. The equation can evaluate the effect cylinder length gives on the stress intensity factor and this effect should be properly considered for cylinders shorter than non-dimensional cylinder length βH≤5.
