Probabilistic seismic hazard analysis and design earthquake for Santiago, Dominican Republic
This article presents the results of a probabilistic seismic hazard analysis (PSHA) conducted for a site in the city of Santiago, located in the Dominican Republic. To perform the PSHA recent seismological data of the Septentrional fault (seismic source) is used to calibrate an earthquake recurrence model, and to compute the seismic hazard curves of several earthquake, ground motion, and structural response parameters of interest in earthquake engineering applications. The parameters studied include horizontal peak ground acceleration and 5 % damping pseudo-acceleration response spectrum ordinates. The effect of uncertainty in the seismic fault rupture zone location is studied using a Monte Carlo analysis; for this purpose, the rupture location is treated as a random variable along the fault. The PSHA results are compared to the site design response spectrum with 2 % exceedance probability in 50 years specified in the Dominican Republic building code. It is concluded that there is a 17 % probability that the actual 2 % exceedance spectrum ordinates are greater than those specified in the design spectrum due to uncertainties related to the attenuation law employed to relate earthquake source and ground motion characteristics at the site. Based on the attenuation model, the design spectrum at the site is consistent with the spectrums generated by a 7.9 (moment) magnitude earthquake, which is close to the 7.8 magnitude characteristic earthquake estimated in previous studies for the Septentrional fault.