Re-calibrating the thresholds for the classification of liquefaction potential index based on the 2004 Niigata-ken Chuetsu earthquake

Abstract The liquefaction potential index (LPI) has been applied with increasing frequency to assess the potential for liquefaction-induced ground failures. This paper describes strategies used to re-calibrate the LPI using accepted methods for screening the liquefaction potential and evaluates its application to the seismic hazard mapping of political tracts. In this study soil profiles using standard penetration tests were evaluated using two methods, the Chinese criteria and the Bray–Sancio criteria. The LPI values were then calculated from these profiles at non-liquefied and liquefied sites in Nagaoka City during the 2004 Niigata-ken Chuetsu earthquake in Japan. Our results suggest that 50% of the liquefied sites exhibited LPI values > 15, and 75% of the non-liquefied sites exhibited LPI values  21 and