Tear Straps in Airplane Fuselage

Abstract : A procedure based on dynamic fracture mechanics is proposed for assessing the effectiveness of tear straps in a rupturing airplane fuselage weakened by a row of multiple site damage (MSD). A large deformation, elastic-plastic finite element model of the rupturing fuselage with an unsymmetrical crack flap is used to demonstrate the existence of a mixed mode I and II crack tip deformation and a large axial stress preceding the propagating crack. These numerical results were used to evaluate the dynamic crack curving and crack arrest criteria and hence to assess the possibility of crack curving as the crack approaches a tear strap without the presence of MSD.