GEOSTATISTICAL INTERPOLATION FOR MODELING THE FACTOR OF SAFETY AGAINST LIQUEFACTION (CAPITAL CITY OF ALGERIA)

Abstract

In Algeria, active tectonics is located in the northern region of the country. Further south, the seismicity is expressed, all along the Tell, along the NE–SW direction fold bundles. The present work uses a number of empirical models from geotechnical earthquake engineering in combination with some geostatistics tools to assess the soil liquefaction potential over an extended area at the Airport of Algiers (Algeria), by the kriging approach. The GS+ geostatistics software along with variograms and the kriging method were all applied together for the purpose of modeling the variation of the factor of safety (FS) in the region under study. This approach allowed determining the missing data in that region. This geostatistical method helped to draw three maps at different soil depths, i.e. 1, 3 and 7m. The results obtained revealed that the models developed were potentially capable of accurately estimating the needed data. The factor of safety (FS) against liquefaction is uncorrelated beyond the distance for which the variogram model stabilizes within an interval ranging from 600 km to 1800 km, for the exponential model used in this study. The values of kriging standard deviation or kriging variance indicate that the standard deviation (SD) values are within the interval ranging from 0.505 to 0.779, 0.231 to 0.556 and 0.257 to 0.61 1respectively.