Wind Uplift On Roof Joists

Checking roof diaphragm for wind uplift i have designed a low sloped roof 25 12 to act as a shear diaphram.

Wind uplift on roof joists.

These uplift loads may result in stress reversals in tji roof joists and uplift reactions at bearing locations. The technical bulletin below explains the design considerations such as bottom flange bracing and uplift connections at bearing. At the same time internal air pressure increases due to air infiltration through openings cracks etc. Under typical gravity loading a joist experiences compression stress in the top flange and tension stress in the bottom flange.

This force is referred to as wind uplift. As wind flows over the building the pressure directly above the surface of the roof decreases. When is uplift bridging needed. The metal deck i am using is non composite.

The result is a net upward force on the roofing system. In some cases wind loading can result in uplift loads on roof joists. Wind uplift for metal deck on bar joist wind uplift for metal deck on bar joist yawp1 petroleum op 29 may 20 15 17. This will be true if there are net concentrated up loads.

See the sji code of standard practice for additional information. This webinar will provide a comprehensive review of wind forces on steel joist and joist girder roof systems including wind load determination wind load combinations and wind load application. Tb 125 wind uplift design for trus joist tji roof joists. Wind uplift design for trus joist tji roof joists in many commercial buildings wind loading may result in uplift loads on roof rafters.

I have specified 3 5 inches of concrete which by. How should seismic and wind loads be specified. New uplift loads can induce stress reversals in tji roof joists as well as uplift reactions at bearing locations. Specification analysis and design to resist uplift loads will be a primary focus but also load paths and connections for wind moment frames collectors and braces.