ANALISIS STABILITAS DAN PENURUNAN TIMBUNAN MENGGUNAKAN EPS GEOFOAM DENGAN VARIASI KONFIGURASI JALAN TOL BAYUNG LENCIR–TEMPINO

Abstrak

Embankments constructed on soft soil commonly experience excessive settlement and low stability due to limited bearing capacity. The use of lightweight materials such as Expanded Polystyrene (EPS) Geofoam has been proposed to reduce vertical stress and improve embankment performance. This study aims to evaluate the effect of EPS Geofoam configuration on settlement and stability of embankments on soft soil. The analysis was conducted on Section 3 of the Bayung Lencir–Tempino Toll Road using the Finite Element Method with Plaxis 2D and the Mohr-Coulomb model. Three EPS configurations were analyzed: 0% (without EPS), 50%, and 100% of the embankment height. The simulation considered static and pseudostatic loading, as well as short-term and long-term consolidation behavior. The results indicate that EPS Geofoam significantly reduces settlement and increases the safety factor. The embankment without EPS shows a settlement of approximately 2.15 m with a safety factor of 1.4. The use of 50% EPS reduces settlement to about 1.4 m and increases the safety factor to 1.8, while 100% EPS results in the lowest settlement of approximately 1.06 m and the highest safety factor of 2.26. Therefore, the 100% EPS Geofoam configuration provides the most optimal performance in improving embankment stability and reducing settlement on soft soil.