This specification covers the requirements for material, geometric, and wall section properties of aluminum box culverts manufactured from corrugated plate or sheet with attached rib stiffeners, for field assembly. Suitable fasteners and optional materials such as aluminum invert plates and headwalls are also described here. Material applications include surface water gravity flow drainage conduits like culverts and storm drains, small bridge, and grade separation structure conduits like pedestrian or vehicular underpasses, and utility tunnels. This specification does not cover the requirements for foundations, backfill, the relationship between earth cover or live loads and strength requirements, or the hydraulic design of these structures. The required plastic moment capacities should be determined for both the crown and haunch segments of the box culverts.

1.1 This specification covers material, geometric, and wall section properties of aluminum box culverts manufactured from corrugated plate or sheet, with attached rib stiffeners, for field assembly. Appropriate fasteners and optional materials, such as aluminum invert plates and headwalls, are also described. Applications for aluminum box culverts include conduits for gravity flow drainage of surface water, such as culverts and storm drains, as well as for small bridges and grade separation structures such as pedestrian or vehicular underpasses, and utility tunnels.

1.2 This specification does not include requirements for foundations, backfill, or the relationship between earth cover or live loads and strength requirements. These important design considerations are described in the AASHTO Standard Specifications for Highway Bridges.

1.3 This specification does not include requirements for the hydraulic design of these structures. Hydraulic design, placement of footings or inverts, and end treatments to resist scour are described in FHWA HDS No. 5.

1.4 lists nominal dimensions of box culvert sizes commonly available. Also listed are cross-sectional area and hydraulic design parameters for these sizes.

1.5 lists manufacturer's suggested design properties for the rib stiffener types, spacing classes, and material thicknesses described in this specification.

1.6 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.