In this work, a numerical model based on the Particle Finite Element Method (PFEM) for the simulation of extrusion-based additive manufacturing of fresh concrete is presented. The balance of momentum and mass are solved with a mixed velocity-pressure formulation in an updated Lagrangian framework. The constitutive law is based on a Bingham model, that is approximated by a Perzyna formulation in order to account for the elastic regime before yielding, which is relevant for the analysis of printed material at rest. The channel flow test, a numerical benchmark for the flow of fresh concrete, is used to validate the model. Finally, 2D examples of extrusion-based additive manufacturing processes of fresh concrete are discussed.