Seismic performance assessment of Eurocode 8-compliant concentric braced frame buildings using FEMA P-58

Abstract

Damage to nonstructural systems during recent earthquakes has resulted in costly repairs and extended building downtime. Achieving a desired seismic performance requires the coordination of structural and nonstructural performance. Eurocode 8 prescribes interstorey drift limits with the aim of controlling nonstructural damage, but a better understanding of the effectiveness of this approach is needed. This study assesses the seismic performance of Eurocode-compliant concentric braced frame buildings designed to meet different drift limits. The FEMA P-58 procedure is used to estimate repair costs. The assessments indicated that many structures designed to modern standards may be demolished following a ULS earthquake due to the high repair costs. Substantial SLS repair costs are also expected. The majority of repair costs can be attributed to nonstructural systems. Storeys satisfying the Eurocode drift limit nevertheless experienced both drift-sensitive and acceleration-sensitive nonstructural damage. Although codes focus on drifts when considering nonstructural response, acceleration-sensitive damage is of comparable or greater consequence than drift-sensitive damage. The repair cost calculations were found to be sensitive to nonstructural quantities and nonstructural elements’ seismic design categorization. The results suggest that modern building standards do not reliably deliver earthquake resilience.