In this study, the authors propose a new technique of adding small-diameter high-strength bolts near the crack to reduce the stress concentration in the stop-hole repaired by the patch plates. In order to confirm the effectiveness of the proposed method, tensile tests and finite element analyses were conducted on specimens with slits and stop-holes in the main plate and patch plates applied from both sides. As a result, it is clarified that the axial load sharing of the patch plate in the stophole increases due to the effect of shortening the distance between the small-diameter bolts, and the stress concentration in the stop-hole wall can be reduced in the elastic behavior range by the proposed method.
