ANALYSIS OF EMBANKMENTS ON SOFT SOIL AREAS WITH LAYER THICKNESS VARIATIONS (CASE STUDY: TOLL ROAD IN LANGKAT REGENCY)

• Main Author: Ikrimah
• Format: Theses
• Language: Indonesia
• Subjects: Teknik sipil
• Online Access: https://digilib.itb.ac.id/gdl/view/87269
• Institution: Institut Teknologi Bandung

Embankment works on soft soil pose significant challenges in toll road construction. In the embankment work for the toll road project in Langkat Regency, locations with varying soft soil thicknesses were found, resulting in settlement in the roadbed. After conducting soil investigations, a thick layer of soft soil beneath the subgrade layer was discovered on the right side of the roadbed. This study aims to analyze the impact of soft soil on embankment stability and evaluate the soil reiriforcement methods applicable to the site. The study analyzes the initial design using three analysis models: Mohr-Coulomb, Hardening Soil, and Soft Soil models. Subsequently, reiriforcement methods were evaluated using two techniques: pile embankment and stone column, with the equations calibrated from the field soil investigation results to obtain accurate soil parameters. The analysis was performed using Finite Element Method (FEM) software, Plaxis 2D. The results showed that the failure conditions in the initial design were consistent with the findings from the additional soil investigation, where failure occurred at a 2-meter embankment depth. The pile embankment method yielded a minimum safety factor of 1.82 with a minimum settlement of-5.3 cm, while the stone column method resulted in a minimum safety factor of 1.29 with a minimum settlement of-8.5 cm. This study provides valuable insights into selecting the optimal soil reiriforcement method for embankment works on soft soil with varying layer thickness.