Liquefaction potential analysis using simplified procedure (Case study: Stadium construction project in North Sumatra, Indonesia)

Abstract Indonesia’s Seismic Design Standards determine that soils in high-seismicity areas with layers of loose sandy soil and a shallow groundwater level require the calculation of liquefaction potential. According to the Indonesian Liquefaction Vulnerability Zone, North Sumatra is categorized as a liquefaction area. Based on these requirements, this research investigates the liquefaction potential of the Stadium Construction Project in North Sumatra. The study area consists mostly of sand with shallow groundwater levels and high seismic zones associated with the Renun-A fault. Soil investigation data, such as Standard Penetration Test, SPT and groundwater level served as the main data for liquefaction potential analyses. The calculation was done using the SPT-based liquefaction triggering analysis by Idriss and Boulanger method for 3 boreholes with a depth of 40 m. This method considered factors such as the Cyclic Stress Ratio and Cyclic Resistance Ratio to determine the safety factor against liquefaction. Peak ground acceleration was obtained from probabilistic seismic hazard analysis, PSHA and deterministic seismic hazard analysis, DSHA. The PSHA is based on the Indonesian earthquake hazard map from the National Earthquake Study Centre of Indonesia with a probability exceeding 2% in 50 years. The DSHA is calculated based on earthquake sources around the research location according to the Seismic Hazard Deaggregation Map of Indonesia. Based on this analysis, the PGA used is 0.303 g. It is concluded that the presence of liquefaction layers was identified at depths ranging from 4 to 17 meters for three bore-hole locations.