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This study used multicriteria decision analysis to quantitatively compare two prototype buildings, both designed using equivalent mass timber and steel structural systems across four decision criteria of seismic resiliency, global warming potential, superstructure cost, and durability. The 5-story and 12-story prototype buildings were both located at an arbitrary site in Seattle, WA. The first three decision criteria were quantitatively measured for each prototype building and durability was assumed to be equivalent between the alternatives. Seismic resiliency was measured using the median expected annual loss calculated using as a percentage of predicted building replacement cost using a procedure in line with FEMA P-58. The global warming potential was measured over the production, construction, and end-of-life stages using the life-cycle analysis program Athena Impact Estimator for Buildings (IE4B). The superstructure cost was calculated as the average cost per square meter using 10 estimating variations that attempt to account for uncertainty in market rates of material, labor, and mass timber design efficiency. Five decision-maker scenarios were analyzed that span the practical range of decision-maker priorities, as informed by discussions with architects and engineers active in the Pacific Northwest. Results from this study showed that for decision-maker cases where the global warming priority was low, steel buildings were the preferred choice. For cases with moderate to high global warming priority and low priority on cost, mass timber buildings were the preferred choice. However, for decision-maker scenarios with moderate priority on both global warming potential and cost, the steel and mass timber buildings were approximately equivalent. Finally, a hybrid steel–timber alternative was presented as a possible sweet-spot solution that merged the benefits of each building material and minimized their drawbacks, making it the most-preferred solution for the case of moderate priority on both cost and global warming potential. The hybrid case was also close second in ranked choice for all other scenarios examined. [ABSTRACT FROM AUTHOR]

This paper presents the structural response of prescriptively designed buckling restrained braced frame buildings to four ground motion sets with different fault characteristics. The four ground motion sets are characteristic of far field, near field with pulse, near field with no pulse, and subduction zone long duration earthquakes. Two prototype buildings of different heights were used for the analysis and designed for a site in Seattle, WA. The analysis was conducted using three-dimensional numerical models of the prototype buildings developed in OpenSeesPy. The simulated buckling restrained brace response was validated with three experimental tests from the literature. The analysis results were used to investigate the effect of ground motion type on the structural response parameters of inter story drift, peak floor velocity, peak floor acceleration, residual inter story drift, and cumulative ductility demand. Results show that the near field motions increase the inter story drift demand compared to far field and long duration motions. All motion sets were likely to cause some level of structural and non-structural damage to drift, velocity, and acceleration sensitive components at the DE and MCE R hazard levels, but severe damage states may not be highly likely. The median residual inter story drift was less than 0.5% for all motion sets. The cumulative ductility demand of the subduction zone long duration motion set was 5 to 6 times greater than that of the far field or near field motion sets and exceeded the code-minimum cumulative ductility for prequalification for upwards of 60% of the analyses. • Study results confirm that near-field earthquakes result in large story drift than far-field earthquakes. • Code-designed BRBFs are likely to have low levels of nonstructural damage. • Code-designed BRBFs are unlikely to have severe levels of nonstructural damage. • Long-duration earthquakes result in 5–6 times more cumulative ductility demand than near-field or far-field earthquakes. • Long-duration earthquakes have cumulative ductility demand in excess of minimum code requirements for pre-qualified BRBs. [ABSTRACT FROM AUTHOR]