LIQUEFACTION POTENTIAL ANALYSIS BASED ON CONE PENETRATION TEST (CPT) DATA IN SEPAKU DISTRICT, PENAJAM PASER UTARA REGENCY, KALIMANTAN TIMUR PROVINCE

• Main Author: Setya Mahendra, Karya
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/53131
• Institution: Institut Teknologi Bandung

Endeavors to move the capital city of Indonesia from DKI Jakarta to East Kalimantan have been initiated since 2019, motivated by the low risk of natural disasters in the East Kalimantan region. However, the East Kalimantan region is not completely safe from natural disasters because there are fault structures that have the potential to cause natural disasters, one of which is an earthquake that can cause secondary impacts in the form of liquefaction. The purpose of this study was to analyze the potential for liquefaction in Sepaku District, Penajam Paser Utara Regency, East Kalimantan Province. In this study, cone penetration test (CPT) data and seismicity data were used in the research area. To analyze the potential for liquefaction in the study area, an empirical method was used which was formulated by Seed and Idriss in 1971 and Robertson and Wride in 1998. Basically, this method compares the variables that trigger liquefaction and the variable soil resistance to liquefaction. The variable that triggers liquefaction is represented by the cyclic stress ratio (CSR), while the soil resistance variable to liquefaction is represented as the cyclic resistance ratio (CRR). If the CSR value is greater than the CRR value, the measurement point will be considered to have the potential for liquefaction. Meanwhile, if the CSR value is smaller than the CRR value, the measurement point will be considered not to have the potential for liquefaction. The comparison between the CSR and CRR values is represented as a factor of safety (FS). Then, the liquefaction potential index (LPI) value is also calculated for analysis. The results of the LPI calculation will be classified based on the classification made by Iwasaki in 1981 and show that in the study area there are points that have high and low potential. From the results of the LPI calculation, a microzonation map of the liquefaction potential in the study area can be made