Stress concentration factor in plates with permanent plastic deformation

Aircraft wings and fuselage may be subjected to accidental deformations during production or service, usually causing visible dents on the sheet metal. Dents caused can reduce the load carrying capacity of a certain structure. The visible dents are unacceptable and immediately flattened or repaired by structural patching. Some dents need not be immediately repaired and by finding the critical dent height we can determine the dent to be acceptable or unacceptable to remain in the aircraft structure without any repair procedure.;The objective of this work is to study the stress concentration factor due to presence of dent on sheet metal. Unlike the previous studies dent is not pre-assumed. The dent is created by using softwares like Ansys APDL, Ansys Workbench 12.1 and PRO/E Wildfire 5.0. Stress concentration factor for different dent shape, stress distribution along the dent contour and loading conditions are obtained and compared with previous results. It is also concluded that the stress concentration factor does not only depend on the h/t factor but also the thickness of the plate.