Stress analysis of ply drop-off in composite structures

A combination of analytical and numerical method is employed to solve the ply drop-off problem. The singular stress fields in the drop-off region are characterized by using the eigenfunction expansion method. A global element capable of capturing the singular behavior is developed and incorporated into a general finite element analysis to provide an overall accurate solution of the stress fields in the ply drop-off region. This facilitates the use of a coarse mesh at the ply drop-off location even there are singular fields. The validation of the global–local finite element method has been carried out with the help of numerical examples.