Modeling of crack formation in a perforated stringer panel

The problem of fracture mechanics concerning the origination of cracks in a plate supported by transverse stringers with an infinite series of circular holes is considered. Mathematical description is given of the model of the origination of the cracks. The action of stringers is simulated by unknown equivalent lumped forces at the points of connection between the ribs and the plate. Determination of the unknown parameters characterizing a germinal crack is reduced to the solution of a singular integral equation. From the solution of this equation, the forces in the origination band of the crack are found. The condition determining the critical external load at which the crack is formed is obtained.