This project conducts a detailed earthquake response study of two midrise reinforced concrete structures which were heavily damaged during the December 1988 Armenia earthquake. Such structures employed a central core with the floor slabs extending outward are also commonly used in seismic regions of the United States. Both the elastic and inelastic responses will be investigated. Lateral force design provisions will be reviewed and economical strengthening methods will be considered. This study will produce valuable information on the dynamic response characteristics of this type of framing system based on the comparison of the observed damage and the analytical results. The current design requirements of this type of structure will be verified on a rational basis.
