Box girder bridge

Box girder bridge

Underneath the No. 2 Road Bridge in Richmond, British Columbia, Canada
Ancestor	Tubular bridge
Related	jetway, skyway
Descendant	segmental bridge
Carries	Pedestrians, automobiles, trucks, light rail, heavy rail
Span range	Medium
Material	Steel, reinforced concrete, prestressed concrete
Movable	Possible
Design effort	High
Falsework required	Yes, if cast-in-place reinforced or prestressed concrete is used, which is typical for freeway overpasses

A box girder bridge, or box section bridge, is a bridge in which the main beams comprise girders in the shape of a hollow box. The box girder normally comprises prestressed concrete, structural steel, or a composite of steel and reinforced concrete. The box is typically rectangular or trapezoidal in cross-section. Box girder bridges are commonly used for highway flyovers and for modern elevated structures of light rail transport. Although the box girder bridge is normally a form of beam bridge, box girders may also be used on cable-stayed and other bridges.