Polyelectrolyte polymer gels can significantly increase or decrease their volume by an external stimulus. The reason for this ability is the multiphasic structure of the gel. In the present work, a chemo-electro-poromechanical model is presented, which is supposed to map the swelling behavior of chemically stimulated polymer gels. The presented model was implemented in COMSOL Multiphysics^®, and the swelling behavior of an acrylamide gel was simulated afterward. The mechanical parameters were obtained from experimental data using a least square optimization while the other material parameters were calibrated to the experimentally determined swelling behavior.