Applications of Fracture Mechanics to Crack Growth at Notches Numerical Solution: Newman 1971 L* L*: Transitional crack length For crack length l ≥ 10% c: crack effective length is from tip to tip!!! (including notch) Example: 2c = 5 mm, L* = 0.25 mm 2c = 25 mm, L* = 1.21 mm

Variación de la tensión con la distancia: Para r = 1.25 ro: Kt cae de 3 ->2

Consequences: plane window For relatively small (5-10 % notch size) cracks at a hole or at a notch, the stress intensity factor K is approximately the same as for a much larger crack with a length that includes the hole diameter / notch depth. Reading: Fatige and the Comet Airplane (taken from S. Suresh, Fatigue of Materials)