Improving Mechanical Properties of Soft Clay by Deep Soil Mixing in North Delta, Egypt vs. Finite Element Simulation

Soft clay layers in the Northern Nile Delta pose significant geotechnical challenges due to low shear strength, high compressibility, and susceptibility to settlement. This study implements a section of a canal embankment in the field using Deep Soil Mixing (DSM) with a cement content of 165 kg/m3 and aims to evaluate its effectiveness in stabilizing soft clay while providing practical design tools for similar deltaic environments. Long-term field monitoring and laboratory testing, including UCS and permeability measurements, were conducted to support the analysis. A Finite Element Model (FEM) was developed in PLAXIS 2D v21 and calibrated against field data, showing excellent agreement with similarity ratios of 91.6% and 95% at monitoring points. Parametric analysis revealed that optimizing cement content significantly reduced both vertical and horizontal displacements while improving the factor of safety. Empirical equations were developed to predict displacements based on cement content and soil cohesion, providing practical guidance for engineers and advancing scientific understanding of DSM behavior in soft clay soils. The results confirm the effectiveness of DSM in stabilizing soft clay and offer both theoretical and field-based contributions to the design of infrastructure projects on soft clay soils.