Influence of Lateral Load Bracing Systems on Damage and Survivability of Residential Structures Impacted by the Moore Oklahoma Tornado of May 20th, 2013

摘要

The Moore, OK tornados provide a rare glimpse of an extreme tornado event (EF-5) occurring at the same relative geographical location twice in fourteen years. Evidence from the May 3rd 1999 and May 20th 2013 events were considered with a special emphasis on the lateral load bracing systems and the influence of building code requirements. The team focused on residential structures and the lateral bracing failures evidenced in these types of buildings. Residential homes built using the continuous sheathing method (R602.10.4 of the 2009 IRC) were compared to the intermittent bracing methods (Table R602.10.2 of the 2009 IRC) or the prior local codes (CABO 1995) which did not incorporate wind speed design parameters. The long term focus is to improve residential construction techniques so that the structures will generally performed better, with a higher structural survivability and a narrower damage path due to a tornado.