The support structure shall consist of a 12” (minimum) box truss steel frame. The steel frame structures shall be all welded trusses made from angles and rounds of sufficient size and strength to withstand design stresses. Steel components in structural frames shall be notched and fitted prior to welding. Overlapping in corners will not be permitted. Side frames of box truss shall include notched angles installed vertically between the top and bottom chords at each division (normally on either 3’ or 4’ centers). All notched connections shall be welded both on the inside and outside, and the outside welds shall be ground smooth prior to galvanizing. All angle members shall be not less than 2” x 2” x 3/16” angle after fabrication. Truss depth shall be not less than 12”. All bolt holes shall be standard sized round holes to fit standard bolts. Holes may be reamed to remove access galvanizing and shall be coated with spray galvanized. All steel frames shall be hot-dipped galvanized after fabrication in accordance with ASTM 123. Field welding of galvanized metals will not be allowed except on minor corrections above water level, which will be treated with cold galvanized process. The steel frames shall be designed for field connection with Grade 5 galvanized bolts. Connections shall be so designed that units may be disconnected and moved.
