Designing embankments on soft ground presents significant engineering challenges due to low shear strength, high compressibility, and potential risk for long-term settlement. This case study of Dohazari Cox’s Bazar Railway Project (DCRP) investigates the design of an embankment constructed on soft soil conditions, focusing on geotechnical assessment, ground improvement strategies, and risk assessment. Detailed site investigations revealed the presence of soft clay layers with low bearing capacity, necessitating the adoption of specialized ground improvement techniques such as prefabricated vertical drains (PVDs), staged construction, and preloading to accelerate consolidation and enhance stability. High strength geotextiles are also used for the stability purpose. Numerical modeling and stability analyses were conducted to optimize the design parameters, ensuring safety against slope failure and excessive deformation. Instrumentation data collected during and after construction validated the design approach and confirmed the effectiveness of the mitigation measures. This study provides practical insights and design recommendations for engineers and practitioners dealing with infrastructure development on soft subsoil, emphasizing the importance of adaptive and evidence-based engineering in soft ground environments.
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