This research sought to determine the practically-viable values of strength and thickness for an overlay, along with the big bond's strength and toughness. By achieving this aim, it is ensured that the overlaying system has adequate ductility and, thus, a high resistance to the emergence and propagation of cracking. The paper has also examined the behavior of NLFEA-modeled bridge deck panels made of pre-casted concrete with a complete depth and how the overlay's strength and thickness influenced such a system. The NLFEA-devised deck panel model was put to validation against the experimentally achieved outcomes of credible published research. Twenty models of precast concrete bridge deck panels were devised. The study parameters were the overlay's ratio of overlay thickness-to-thickness of bridge deck slab (toverlay/tslab); and the overlay's relative ratio of the strength of overlay-to-strength of deck slab (Eoverlay/Eslab). For experimentation purposes, the former ratio was set at the values of 0.00 (no thickness), 0.05, 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40, 0.45, and 0.50, while the latter ratio was set at 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1.0. The outcomes of this research paper greatly assisted in recommending a set of somewhat useful guidelines to help determine the best overlay's strength and strength suitable to eliminate potential delaminating of the deck's overlay exposed to service load and overload due to AASHTO HS-20 truck and impact loading.