Potential benefits of seismic monitoring for ground shaking estimation and loss assessment

Abstract

Seismic networks are fundamental to compute ground shaking in regions affected by destructive events, which can then be used for damage and loss assessment. Ground‐motion data recordings can be used to estimate the event bias (or interevent residual) for one or multiple ground‐motion models, as well as to condition the ground‐shaking estimation process to reduce the intraevent residuals at sites near seismic stations. We evaluate how the error in the estimation of the event bias and ground shaking for a set of target sites can be reduced by incorporating an increasing number of seismic stations, using recordings from the 1999 M 7.7 Chi‐Chi, Taiwan, earthquake and a large set of ground‐motion fields for Taiwan using stochastic simulations. Then, we evaluate how the incorporation of data from seismic stations in the estimation of several impact metrics (i.e., economic losses, collapsed buildings, and fatalities) can reduce both the bias and the uncertainty, using the district of Lisbon (Portugal) as a case study. The results from this study indicate that the error in the estimation of the impact metrics can be reduced by one order of magnitude if at least 10 stations are considered, especially if the configuration of the seismic network considers the location of vulnerable buildings or the spatial distribution of earthquake risk.