Comparison of damage to nonstructural components (suspended ceilings) in large enclosures by Niigata-Chuetsu and Chuetsu-Oki earthquakes

One week after the Niigata-Chuetsu-Oki earthquake, 2007, the authors investigated damage to non-structural components, especially suspended ceilings, in six large enclosures at Nagaoka City. All of the six enclosures had damage to suspended ceilings in 2004 Niigata-Chuetsu earthquake and have made certain recovery works and improvements to their ceiling systems. In this paper the authors compare the damage in these six structures in both earthquakes and try to examine the validity of the improvements that have been made between the two earthquakes.