Antiseismic structure: damper-equipped elastic frame

Conventional antiseismic design of reinforced-concrete (RC) building structures admits inelastic behaviour as a necessary condition to meet requirements of strength and damping, as well as initial-cost economy of the structures. This inelastic behaviour eventually translates into structural damage that may be expensive to repair and also cause considerable inconvenience. This work undertakes the design of an antiseismic, damper-equipped, elastic-frame RC building structure on the basis of regulations specified in the Mexico City building code but generic to any code. Maintaining ample strength, the frame of the structure is designed to behave elastically up to the limit of the storey displacements permitted by the building code. Mild steel dampers, incorporated in the structural frame, provide effective damping, as well as stiffness to resist wind forces adequately. Designing the frame exclusively for elastic behaviour is aimed at diminishing the possibility of structural damage under seismic forces, thus enhancing the economic viability of the structure, provided repair-related cost savings during the life cycle of the structure are taken into account.