The fracture mechanics approach involves inserting small semi-elliptical surface crack at different open-hole locations
and extracting maximum stress intensity factors along crack fronts. It was observed KI drops linearly with distance and
approaches Kthreshold at adistance of around 75 mm from its initial location.In Fig. 12(b), KI remains above Kthreshold at 45mm
and an aggressive open-hole would stilllead to crack propagation under fatigue loading at that distance.This study provides
a comparative view of two design approaches and helps identify anodrill zone on framerails near high stress areas