Development and verification of seismic capacity and ductility demand estimation procedures for coupled core wall systems

Performance-based seismic design of tall buildings is of great importance as demands are increasing for incorporating structural safety in such challenging structures. Although a number of design guidelines and consensus documents have been published in the last few years regarding performance-based seismic design of tall buildings, there are still several issues need to be resolved. Coupled core wall systems composed of flanged (U, T, E or I shaped) walls coupled by coupling beams, represent the most commonly used structural system in tall buildings. Although experimental and analytical research is available regarding the behavior of coupled wall systems with rectangular walls, such systems are not representative of the current design practice. Efforts are necessary not only for a clear understanding of the behavior of coupled core walls both at the component and system levels, but at the same time for the implementation of research results into performance-based seismic design methodologies. In this study, capacity and ductility demand estimation procedures are developed for preliminary seismic design of coupled core wall systems. These procedures may be considered complementary to capacity design principles to be implemented during the preliminary design stage. Effective design parameters controlling the behavior of coupled core wall systems and relative importance of each design parameter are identified through verification studies of the proposed capacity and ductility demand estimation procedures as well as nonlinear response history analyses.