SEISMIC RESPONSE OF ASYMMETRIC SYSTEMS: ENERGY-BASED ApPROACH

An energy-based approach has been used to investigate the seismic behavior of code-designed asymmetric-plan systems. The systems considered in this investigation had large eccentricities in both directions, were designed for bidirectional earthquake loading, and their responses were computed with both components of ground motion acting simultaneously. The presented results demonstrate that the total input energy is about the same whether the system plan is symmetric or asymmetric. Furthermore, flexible-side elements in asym­ metric-plan systems may be more vulnerable to earthquakes than the same elements in symmetric-plan systems if they are not designed to accommodate the higher hysteretic-energy demands. This observation correlates well with the damage observed in street comer buildings during several earthquakes. Stiff-side elements, on the other hand, are expected to suffer no more damage in asymmetric-plan systems than in symmetric-plan systems.