A powerful method for partitioning mixed-mode fractures on rigid interfaces in laminated unidirectional double cantilever beams (DCBs) is developed by taking 2D elasticity into consideration in a novel way. Pure modes based on 2D elasticity are obtained by introducing correction factors into the beam-theory-based mechanical conditions. These 2D-elasticity-based pure modes are then used to derive a 2D-elasticity-based partition theory for mixed-mode fractures. Excellent agreement is observed between the present partition theory and Suo and Hutchinson’s partition theory (Suo and Hutchinson, 1990) [1]. Furthermore, the method that is developed in this work has a stronger capability for solving more complex mixed-mode partition problems, for example, in the bimaterial case (Suo and Hutchinson, 1990)
