Study of Liquefaction Severity-induced Lateral Displacement and Settlement based on SPT Data in Toll Road Project (Case Study: Mungkid and Candimulyo Districts, Central Java, Indonesia)

¹ Department of Civil and Environmental Engineering, Faculty of Engineering, Universitas Gadjah Mada, Yogyakarta, Indonesia
² Directorate General of Highways, Ministry of Public Works and Housing, Republic of Indonesia Jakarta, Indonesia

^* Corresponding author: sito.ismanti@ugm.ac.id

Abstract

The common phenomena during liquefaction are the lateral displacement and settlement of saturated soil deposits. These phenomena have the potential damage to the toll road construction where this research is taking place. Toll road projects in Mungkid and Candimulyo Districts, Central Java, Indonesia must be evaluated for lateral displacement and settlement. The study area is located in volcanic deposits originating from Mount Merapi and Merbabu, with shallow groundwater level in some location, and a history big seismicity. PGA value at the research location was calculated using webpage application from Lini Binamarga. This study aims to calculate liquefaction severity using LSI method, lateral spreading using LDI method, and the ground settlement using reconsolidation settlement method with various moment magnitude scenarios. LSI in Candimulyo and Mungkid District are 17.77 (low severity) and 9.68 (very low severity), respectively. Candimulyo and Mungkid Districts experienced the greatest lateral spreading of 3.84 m and 1.87 m. Also, Candimulyo and Mungkid Districts have the largest settlement by 0.42 m in the extensive damage category and 0.15 m in the medium damage category. Based on this assessment, it is necessary to investigate the mitigation required to reduce lateral spreading and settlement caused by liquefaction.