Numerical simulation of interface debonding with a combined damage/friction constitutive model

Experimental studies for pull-out tests in fiber-reinforced composites reve al a softening behaviour due to interface crack growth between fiber and ma trix followed by a contact friction behaviour on the cracked area. In this contribution this debonding process is modelled within the framework of int erface damage mechanics, where the displacement discontinuities during the progressive decohesion are related to constitutive equations extended by an anisotropic damage model. The contact/ friction behaviour after complete s eparation is described by a friction model analogously to the classical the ory of plasticity. The simulation of the load-displacement curve in the pul l-out test with the drop-off behaviour is achieved by introducing a Hermite polynomial. The numerical simulations are performed for glas/polystyrol fi ber-reinforced composites, thus illustrating the progressive debonding and friction between both constituents and demonstrating a good agreement with experimental data of a pull-out test.