New Zealand specific consequence functions for seismic loss assessment

Abstract

Quantitative seismic loss assessment has become an increasingly popular tool for evaluating the seismic performance of structures. The growth in popularity is largely in response to a desire to look beyond the traditional life safety performance objective and instead consider also economic losses and downtime due to earthquakes. A key step in the loss assessment calculation process is relating damage in both structural and nonstructural components to appropriate repair strategies and subsequently repair costs and repair times. This is achieved through the use of so-called consequence functions, which in this paper are derived specifically for the New Zealand context. Furthermore, a framework is established for other researchers and professional engineers to continue to build on and improve the initial dataset. It is shown that using New Zealand specific consequence functions can have a noticeable effect on estimates of expected annual loss when compared to a benchmark case using consequence functions from FEMA P-58. The opportunity is also taken to evaluate the impact of recent updates to the New Zealand National Seismic Hazard Model, with the results for a case-study building in Wellington indicating that the change in hazard has a far more significant effect on estimates of loss when compared to the choice of different consequence functions.