Secondary Structural Members
Secondary structural members include roof purlins, wall girts, eave struts,-C sections, flange braces, gable angles and base angles. Purlins, Girts, Eave Struts and C-Sections ( used as base channels and as door jambs and headers in framed openings of double sliding doors and Roll Up Doors ) are rolled formed from 345mm wide galvanized coils in thickness of 1.5, 1.75, 2.0, 2.25 and 2.5 mm. They are made from material that conformes to ASTM A653M Grade SS : 340 Class IG90 and are designed in accordance with the 2002 cold formed s
- teel design Manual, published by “The American Iron and Steel Institute”(AISI)
A common practice in the PEB industry is to connect the sidewall girts to the sidewall rigid frame columns in a
flush condition. The by pass approch is more practical, even in endwalls, because it allows cables, pipes, etc. to be laid within the 200mm girt line all around the building. It also allows for a better construction of partial height blockwalls (normally 2.25 to 3.00m heigh) which are very common in this region.
Flange Stay With Lap
Flange Braces are 4 or 5 mm thick angle sections used to prevent rigid frame members from twisting or buckling laterally under load. They are used on one side or both sides of the rafters/ columns depending on the magnitude of the required restraining loads.
Base Angles are fastened to the concrete floor with the masonry nails at 500mm on centers. they transfer the wind load from the wall panels directly to the slab. When interior wall liner is required, a base channel (C-Section) is used in lieu of a base angle.
Gable Angles are connected to bottom flanges of roof purlins at building ends using self-drilling fasteners. They transfer the wind load from the endwall panels (which are fastened to this gable angle ) to the roof purlins, at the gable end of the building.