In this paper, a rate dependent model is developed to simulate the bridging performance of z-pins subject to Mode I and Mode II loading. Z-pins are modelled as beams embedded in a Winkler elastic foundation with friction. The latter is described via Ruina's state dependent friction model in order to incorporate the rate effect. The Ruina's model parameters were calibrated against a Mode I and Mode II test carried out at a pullout speed of 5m/s and 1m/s respectively. The calibrated model was then validated against a mode I and mode II test conducted at 12m/s and 1.5m/s respectively. The predicted force versus opening-displacement trend is in excellent agreement with the experimental one. The error of predicted apparent fracture toughness is within 5% of the experimental value.