"Description: This work shall consist of furnishing@ fabricating@ and installing metal pipe@ metal structural plate pipe@ arches@ pipe arches@ and box structures in conformance with these specifications@ the special provisions@ and the details shown on the plans. As used in this specification@ long-span structures are metal plate horizontal ellipse@ inverted pear and multiple radius arch shapes as well as special shape culverts as defined in Division I@ Section 12@ ""Soil-Corrugated Metal Structure Interaction Systems."" The terms ""metal pipe"" and ""metal structural plate pipe"" shall include both circular pipe arch@ underpass and elliptical shapes. ""Metal structural plate arches"" consist of a metal plate arch supported on reinforced concrete footings at its base (ends) with or without a paved invert slab. ""Pipe arches"" are constructed to form a pipe having an arch-shaped crown and a relatively flat invert. ""Metal structural plate box structures"" are conduits@ rectangular in cross section@ constructed of metal plates."