Structural Systems

Drifts and global displacement ductilities were calculated. Global displacements were related to local inelastic demands. Damage indexes were computed for all buildings. The stiffness of the structural system plays an important role in displacement control. A large reduction in damage can be achieved by including walls as an earthquake resisting system. Interstory drifts can be reduced from 1.3% to 0.85% for Kobe and from 1.9% to 1% in Northridge, in flexible structures, and up to 0.85% for Llolleo and Viña del Mar records, related with moderate damage. If some walls are added, drifts can be diminished to 0.5%, with damage being reduced to very slight or none.