Numerical Implementation of a Cohesive Zone Model in History-Dependent   Materials
  A non-linear history-dependent cohesive zone model of crack propagation in linear elastic and visco-elastic materials is presented. The viscoelasticity is described by a linear Volterra integral operator in time. The normal stress on the cohesive zone satisfies the history dependent yield condition, given by a non-linear Abel-type integral operator. The crack starts propagating, breaking the cohesive zone, when the crack tip opening reaches a prescribed critical value. A numerical algorithm for computing the evolution of the crack and cohesive zone in time is discussed along with some numerical results. 
L. Hakim, S.E. Mikhailov
math.NA