Box culvert sections can be manufactured in a variety of shapes and sizes. They offer a rapid means of construction as the units are designed to carry the full applied loads (e.g. highway loadings for those below roads). While they are most commonly used for water courses, they are also used for pedestrian subways, service tunnels, sea outfalls and balancing tanks.
In the latter case they are supplied complete with end walls and pipe openings. they can also be used vertically to form large cross-section shafts. A range of standard sizes are available, with heights between 600mm and 3m and with spans from 1.2 to 6m. Joints between units are rebated and may be left open but a preformed strip compressed within the joint is commonly used.
Sections are available in suitable sizes for pedestrian subways and underpasses; larger sections will accommodate cars and light commercial vehicles. Provision can be made for lighting and special finishes. Specially designed sections are available for installation by jacking methods in suitable applications for trenchless construction.