Similar to the Nodal Release Method, the Modified Crack Closure Integral (MCCI) is a method for calculating the energy release rate utilizing FEA nodal displacements ( u i j ) and forces ( F i j ) . Where i represents the direction corresponding to the Cartesian basis vectors with origin at the crack tip, and j represents the nodal index. MCCI is more computationally efficient than the nodal release method because it only requires one analysis for each increment of crack growth.