The construction of toll roads in Indonesia frequently encounters geotechnical challenges due to soft soil conditions. Pile slab construction and road embankments on soft soil are susceptible to future settlement if 90% consolidation has not been achieved or primary settlement remains incomplete—potentially compromising safety and user comfort while causing construction delays. The Patimban Subang Access Toll Road exemplifies such conditions, with NSPT values of ?10 extending to a depth of 10 meters. This study aims to analyze embankment settlement at the transition zone between pile and pile slab segments, comparing scenarios with and without soil replacement treatment. Using the Terzaghi method with 1.5 m replacement on soft soil layers, a cumulative settlement of 87.17 cm was calculated, while Plaxis 2D modeling yielded 96.20 cm. In contrast, manual calculations without replacement predicted a significantly higher settlement of 120.27 cm, demonstrating the effectiveness of soil replacement in reducing total settlement by approximately 27%. The consolidation time to reach a 90% degree of consolidation was estimated at 56 years using the Terzaghi method and 53 years using Plaxis 2D modeling. These findings provide critical insights for optimizing soft soil treatment strategies in toll road construction.
Tambunan et al. (Fri,) studied this question.