A floor panel for a raised access floor system, including a shallow metal pan with a bottom wall and a shallow upwardly-opening compartment. The bottom wall has a plurality of first hollow projections projecting upwardly therefrom, which projections adjacent upper ends thereof having sidewardly projecting rib structure. The bottom wall also has a plurality of microfeatures which project upwardly through a lesser extent. The number of microfeatures is substantially greater than the number of projections. The pan side walls and bottom wall are free of openings therethrough. A mass of solidified concrete fills the compartment. The floor panel is supported on a pedestal having a base which has clamping and mounting features integrated thereon for engaging grounding wires and cable management members.