A bridge system is provided that utilizes foundation structures that are formed of the combination of precast and cast-in-place concrete. A method of constructing the combination precast and cast-in-place concrete foundation structures involves receiving at a construction site a precast concrete foundation unit having elongated upright wall members that define a channel therebetween, and multiple upright supports located within the channel; placing the precast concrete foundation unit at a desired use location; delivering concrete into the channel while the precast concrete foundation unit remains at the desired use location; and allowing the concrete to cure-in-place such that the elongated upright wall members are connected to the cured-in-place concrete by reinforcement embedded within both the cured-in-place concrete and the upright wall members. The bridge units may be placed before the pouring step to embed the bottoms of the bridge units in the cast-in-place concrete.

A prefabricated modular reinforced concrete building system includes panel assemblies for foundations, walls, decks, and roofs designed to be built out in a manufacturing facility, shipped to a job site, and filled with concrete. Panel assemblies incorporate a space frame to ensure structural integrity during shipping and during concrete fill. Space frames can include structural columns, rebar mats, spacers, straps, and skin panels. Panel assemblies may be manufactured to contain architectural interior/external finishes, windows/doors, and pre-installed utility distribution systems.

A prefabricated modular reinforced concrete building system includes panel assemblies for foundations, walls, decks, and roofs designed to be built out in a manufacturing facility, shipped to a job site, and filled with concrete. Panel assemblies incorporate a space frame to ensure structural integrity during shipping and during concrete fill. Space frames can include structural columns, rebar mats, spacers, straps, and skin panels. Panel assemblies may be manufactured to contain architectural interior/external finishes, windows/doors, and pre-installed utility distribution systems.