Abstract: The paris'displacement formula and the rivet-force-method are adopted to calculating the stress intensity factor for cracked stiffened panel With a circular hole in this paper. The principle of displacement coordination is used to calculate the rivet force. To solve displacement fields of panel with circular hole, we put forward an efficacious method that the state of exerting concentrated force on panel without hole is added to the state of exerting distributed load at hole boundary of panel with hole. Meanwhile formulas of the stress intensity factor at two cracked modes are deduced. The results show that in the case of cracking only at hole boundary the stress intensity factor at crack tip will decrease with increase of stringer stiffness and decrease of rivet distance and that in the case of cracking at the skin and stringers the stringer also has important effect for arresting crack.

Key words: stiffened panel with a circular hole, stress intensity factor, rivet force