Seismic Fragility Testing of Suspended Ceiling Systems

The failure of suspended ceiling systems (SCS) has been one of the most widely reported types of nonstructural damage in past earthquakes. In this research, fragility methods were used to characterize the vulnerability of SCS. Since SCS are not amenable to traditional structural analysis, full-scale experimental testing on an earthquake simulator was performed to obtain the fragility data. Four limit states of response were defined using physical definitions of damage. Based on the fragility data obtained, it was found that (a) the use of retainer clips improved the performance of SCS in terms of loss of tiles, (b) including recycled cross-tees in the assemblage of the suspended grid increased the vulnerability of the SCS, (c) undersized (poorly fitting) tiles are substantially more vulnerable than properly fitted tiles, and (d) including compression posts improves the seismic performance in SCS; however, the effectiveness remains questionable when it is compared with the required installation efforts.