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Reaction of Ceiling Tile Systems to Shocks. Federal Building and Fire Safety Investigation of the World Trade Center Disaster (NIST NCSTAR 1-5D) ***DRAFT for Public Comments***



Richard G. Gann, Michael A. Riley, J M. Repp, A S. Whittaker, Andrei Reinhorn, P A. Hough


The degree of damage to the ceiling tile systems of the World Trade Center towers following the aircraft impacts on September 11, 2001, could have affected the rate at which the ensuing fires heated the steel- trussed concrete slab floor systems above. Accordingly, a series of shaking table tests was conducted to estimate the magnitude of distress to the ceiling tile systems that would result in substantial displacement of ceiling tiles. Ceiling tile systems indicative of those used in the core and tenant spaces were subjected to both single and complex impulses of varying magnitude. The systems resisted significant damage up to about 1g applied to the test platform, corresponding to about 2.5g to 3g at the ceiling frame. The data suggest that major system failure would occur at impulse values near 4g to 5g at the ceiling frame.
National Construction Safety Team Act Reports (NIST NCSTAR) - 1-5
Report Number


World Trade Center, high rise buildings, building collapse, disasters, fire safety, fire investigations, terrorists, terrorism, ceilings, ceiling tiles, experiments, aircraft impact, concretes, floors, damage
Created September 1, 2005, Updated February 19, 2017