Abstract
This study presents a probabilistic model for cumulative damage in composite materials undergoing delamination. The model assumes the presence of numerous weak microvolumes (WMVs) in which fatigue damage can initiate and accumulate. Defect nucleation is described as a Poisson process whose rate does not depend on specimen size. The cumulative distribution function of the fatigue life of each microvolume is obtained using the Poisson formulation, and the overall delamination behavior is interpreted as a brittle-type failure mechanism governed by nodal attachment points in honeycomb structures. Numerical implementation is demonstrated through Excel-based inverse comparison and R-based simulation methods. The results show that Poisson-driven damage evolution provides a viable approach for estimating residual undamaged area and for modelling avalanche-type delamination growth. The methodology offers a foundation for future experimental verification and refinement of stochastic models for composite damage propagation.