Laboratory Investigation of Nanomaterial-Enhanced Electro-osmotic Chemical Consolidation for Stabilizing Soft Clayey Soils

ABSTRACT The engineering utilization of electro-osmotic consolidation (EOC) for soft floodplain clay is frequently hindered by interfacial resistance buildup and uneven strength development. This study investigated an enhanced EOC approach incorporating nanomaterials, a polymer flocculant, and chemical stabilizers to improve drainage efficiency and mechanical performance. A series of laboratory tests were conducted on soft clay to evaluate the effects of different nanomaterials in combination with anionic polyacrylamide (APAM) and chemical solutions, with the aim of identifying an optimized treatment scheme. Soil response was examined in terms of electrical behavior, pore-water discharge, water content evolution, shear strength, and bearing capacity. Microstructural evolution was evaluated using scanning electron microscopy to reveal the consolidation mechanisms. Results showed that nanomaterial incorporation enhanced electro-osmotic drainage by mitigating polarization effects. The optimized system, combining Fe3O4 nanoparticles, APAM, and chemical solutions, achieved increases of 251 % in average shear strength and 110 % in bearing capacity relative to conventional EOC. Microstructural analysis demonstrated a transition from a dispersed clay fabric to a denser aggregated matrix with improved structural integrity and reduced compressibility. These findings indicated that the proposed nanomaterial-enhanced EOC technique provides an efficient solution for soft ground improvement in floodplain environments.