Primary Structures shall be built-up sections made from hot rolled plates. The hot rolled plate, conforming to ASTM A-572 Grade-50 (or equivalent), shall have a minimum yield of 344N/mm2.The hot rolled “I” sections for intermediate columns and crane beams are millformed sections conforming to BS4360, Grade 43A (or equivalent) and shall have a minimum yield of 275N/mm2.
Purlins, girts and eave struts shall be galvanised cold formed “C” or “Z” sections of thickness 1.6mm, 2.0mm and 2.5 mm with a minimum yield of 344N/mm2.
All primary structural connections shall be high-strength bolts conforming to ASTM A-325.All secondary structural connection are connected to their supporting members by machine bolts conforming to ASTM-307.
After meticulous cleaning, one shop-coat of zinc chromate primer shall be applied to all primary framing.