Mapping the liquefaction potential index (LPI) in Ratu Agung subdistrict, Bengkulu City, Indonesia using the shear wave velocity approach

¹ Department of Geological Engineering, Faculty of Engineering, University of Gadjah Mada, Indonesia ;
² Department of Civil Engineering, Faculty of Engineering, University of Bengkulu, Indonesia ;
³ Department of Physics, Faculty of Mathematics and Natural Sciences, University of Bengkulu, Indonesia ;

^* Corresponding Author: mfarid@unib.ac.id

Abstract

On the 4^th of June, 2000 and 12^th of September, 2007, Ratu Agung Sub-district, Indonesia experienced significant damage due to liquefaction after the earthquakes. Therefore, this study aims to determine the Liquefaction Potential Index in the area. Data of shear wave velocity (Vs) was collected using the Multichannel Analysis of Surface Wave (MASW) method. The measurement location was set up on a grid of 32 observations points with field investigations. Furthermore, Simplified Procedure and LPI methods were used to measure the soil liquefaction potential and vulnerability level. The results showed that the value of shear wave velocity in the Ratu Agung Subdistrict ranged from 102 m/s to 442 m/s. Also, the liquefaction vulnerability levels varied from high to very high categories due to the maximum soil acceleration and conditions dominated by loose sand, as well as the influence of different geological formations in the zone. In conclusion, an empirical equation was successfully proposed to analyze the liquefaction vulnerability.