Exploring resiliency between different steel lateral systems for new construction

Abstract

It is known that while base level, code compliant structural designs produce buildings with a low likelihood of collapse, there is little guarantee that buildings will remain functional following moderate to severe earthquakes. Because of this reality, there is a rising focus on issues of resiliency in the design of buildings and encouraging owners and developers to think beyond code minimum designs. While this may be the ideal, the reality is that many buildings are still designed to the base code level. This paper explores how these types of code-compliant buildings stack up in terms of resiliency metrics. For this exploratory study, three building systems common in New Zealand are explored: Eccentric Braced Frames (EBFs), Steel Moment Frames (SMFs) and Steel Moment Frames with Fluid Viscous Dampers (the Taylor Damped Moment Frame, TDMFTM).

The software package, Seismic Performance Prediction Platform (SP3), is used to explore the resiliency metrics for archetypical structures using these three lateral systems. IL2 and IL4 type structures are examined at several seismic hazard levels for a representative site in New Zealand. SP3 operationalizes the FEMA P-58 and ATC-138 frameworks to determine probabilistic distributions of metrics such as expected loss, reoccupancy time, and functional recovery time. Sources of damage and downtime are also explored, and recommendations for structural and non-structural adaptations are discussed that can help improve the resiliency of these types of steel structures.