Liquefaction Potential Index Analysis in Solo – Yogyakarta - NYIA Kulon Progo Toll Road (Section Karanganyar to Klaten Regency) at Central Java

Abstract

Liquefaction had occurred in Yogyakarta due to an earthquake of moment magnitude, Mw 6.3 on May 27, 2006. This earthquake caused severe damage in several areas in Central Java. The study area in this construction was located mostly in some areas of Central Java Province that had a shallow groundwater table and often occurred earthquakes that might trigger liquefaction. The objective of this study was to analyze liquefaction potential in the construction of Solo – Yogyakarta – NYIA Kulon Progo toll road especially sta. 00+000-07+500 From Colomadu, Karanganyar Regency to Delanggu, Klaten Regency using two scenarios based on the existing earthquake history according to USGS data. That were earthquakes with Mw 6.3 and Mw 5.2 on a total of 47 boreholes. This study used data from Standard Penetration Tests (SPT) and laboratory tests. The liquefaction potential analysis used the simplified procedure and Liquefaction Potential Index method. Based on liquefaction potential analysis, an earthquake of Mw 5.2 has a very low liquefaction potential compared to an earthquake of Mw 6.3. According to analysis results and hazards caused, an earthquake with Mw 6.3 is recommended to be used as a basis for mitigation against liquefaction planning.