Silicon Pixel detectors are at the core of the current and planned upgrade of the ATLAS detector. As the detector in closest proximity to the interaction point, these detectors will be exposed to a significant amount of radiation over their lifetime: before the High Luminosity phase of the Large Hadron Collider (HL-LHC) the innermost layers will receive a fluence in excess of $10^{15}$ n$_\mathrm{eq}$/cm$^2$ and the HL-LHC detector upgrades must cope with an order of magnitude higher fluence integrated over their lifetimes. This work presents the details of a new simulation model that includes radiation damage effects to the 3D Pixel sensors for the ATLAS detector.