This paper applies the unit load method to simulate one-and twodimensional delamination growth in composite laminates. A virtual crack closure formulation is incorporated in a finite element program to evaluate the mode-I, mode-II and mode-III strain-energy release rates. Based on the responses of the unit load on the potential cracks, the nodal forces and displacements for the evaluation of strain-energy release rate are solved by a series of linear equations without reanalyzing the finite element model during crack growth. The results show that the use of the unit load method significantly reduces the computational time to simulate the delamination growth in composite laminates.
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