Finite Element Analysis of Ceiling Collapse during Seismic Excitation
Abstract
Collapse phenomena of ceilings have been observed frequently in the past
earthquakes in Japan. It causes not only the possibility of human injuries,
but may disturb the use of the facilities after the earthquakes. In this
study, a finite element analysis of the ceiling collapse in a full-scale
gymnasium during seismic excitation was conducted to investigate the collapse
mechanism of the ceilings. The numerical code used in this study is constituted based upon the adaptively
shifted integration (ASI) – Gauss technique, which provides a higher computational
efficiency than the conventional finite element method by appropriately
shifting the numerical integration points of the finite elements. It can
also handle dynamic phenomena, such as member fracturing, by expressing
the precise locations of fractured sections. The detachments of the ceiling joists and ceiling joist receivers were
considered by setting the sectional forces of the clips, screws and hangers
to be zero once the axial forces acting on these members exceeded the maximum
strength. Collisions between plaster boards and structural components of
the gymnasium were also considered by a contact algorithm introducing gap
elements. The numerical result showed a certain resemblance with an experimental
result which was obtained at the E-Defense shaking table test conducted
in 2014.