This presentation focuses on the simulation of the Brazilian splitting test on mortar samples under monotonic loading using a variational phase-field model based on micromechanics. The model aims to connect macroscale field variables with physical dissipative mechanisms at the microcrack level by linking plasticity with the sliding of closed microcracks and damage with the growth of open microcracks. The study addresses the potential complications of stress concentrations near the applied loads by employing a viscoplasticity regularization within the variational framework. The parameters of the model are calibrated using experimental results from a Brazilian splitting test conducted using Digital Image Correlation (DIC) measurements. The response of a volume element under a homogeneous strain field is presented to examine the effect of the viscosity parameter, and the fracture mode of the Brazilian splitting test is studied to gain a better understanding of different failure modes. Different loading conditions were applied to the volume element to identify different failure modes, utilizing the model’s main feature of distinguishing between fracture modes. The calibrated parameters are then used to assess the validity of the model and its prediction capabilities by applying them to another sample with the same material but different size and boundary conditions. Results show that the numerical failure prediction is consistent with the experiment, confirming the validity and reliability of the simulation model.