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Summarized in this article are the major findings from a detailed damage investigation of an instrumented ductile reinforced concrete moment frame building subjected to a design-level earthquake. The building sustained widespread damage during the 2016 M-7.8 Kaikoura earthquake and was subsequently demolished. Prior to demolition, the structural system was extensively surveyed to document the severity and distribution of the damage sustained in the reinforced concrete frames and the flooring system. Furthermore, the building response during the earthquake was reconstructed from the acceleration records obtained from instruments installed throughout the building. The site seismic demands were also obtained from a local free-field instrument. The data collected from this damage investigation provide a high-quality dataset that is valuable to researchers investigating different parameters related to the seismic performance of reinforced concrete moment frame buildings. The dataset is published and publicly available on DesignSafe-CI (project PRJ-3444); https://www.designsafe-ci.org/data/browser/public/designsafe.storage.published/PRJ-3444v2. The data collection methodology is described, and a roadmap for navigating the dataset is presented to support future use of the archived dataset. [ABSTRACT FROM AUTHOR]

Hollow-core flooring systems were damaged in Wellington buildings during the 2016 Kaikoura earthquake (7.8 Mw) and have been shown to be susceptible to undesirable failure mechanisms (loss of seating, negative moment, and positive moment failure modes) at low drift demands. These undesirable damage mechanisms have also been observed in sub-assembly and super-assembly laboratory testing of hollow-core flooring systems and the test data obtained has enhanced the state-of-the-art knowledge of the probable seismic behaviour of hollow-core floor units. In this study, using currently available sub-assembly test data, fragility functions are defined for hollow-core flooring systems. Furthermore, the proposed fragility functions are combined with fragility information derived from nonlinear dynamic analyses for two eight-storey bare-frame reinforced concrete (RC) buildings designed based on New Zealand standards. This study shows that, in comparison with RC buildings with flooring systems that are not susceptible to gravity load failures, RC buildings with vulnerable hollow-core floors have a significantly higher likelihood of exceeding the collapse prevention limit state, as defined in this study. [ABSTRACT FROM AUTHOR]

Uncertainty about when post‐earthquake repairs are needed delays decision making, and can lead either to unnecessary demolition or repair, or to inadequate repair actions. This study proposes a framework for assessing the effect of earthquake damage on the future seismic performance of a building. In this framework, we first assess drift demands during a maximum considered earthquake (MCER) level ground motion in an undamaged building, and then compare the drift demands in the same building during the same motion when it has been damaged by a prior shaking. We assess each building for a range of prior shaking events and 15 MCER‐level motions. From these analyses, we determine the relationship between damage in the first motion—quantified as peak story drift demand—and the MCER‐level motion drift demands—quantified as the ratio of peak drift demands in the damaged building to those in the undamaged building. This trend is used to indicate the level of damage at which performance is impaired, and repair is needed due to structural safety concerns. We apply this framework to a set of single‐degree‐of‐freedom structures and reinforced concrete moment frame buildings representative of construction in the United States. The results show that code‐conforming structures do not see significant drift amplifications in the damaged building when story drifts in the damaging motion do not exceed 2%, indicating they would not require major repairs for structural safety. Structures with less deformation capacity saw larger amplifications, and were affected when story drift demands in the damaging motion were lower. We also found that stiffer structures tend to see larger amplifications of drift demands. [ABSTRACT FROM AUTHOR]