Effect of nanomaterials and electrode configuration on soil consolidation by electroosmosis: experimental and modeling studies

Abstract

Controlling the water content in soil is crucial for the load bearing capacity of soil. In the past few decades, electroosmosis has been proved to be a versatile strategy to consolidate soil in situ. However, the efficiency of this electrochemical technique needs to be further improved for practical application. This study was designed to test the hypothesis that the incorporation of nanoparticles (NPs) during electroosmosis can significantly facilitate the migration of water molecules under an external electric field and thus improve the physical properties of the treated soil. In addition, the number of anodes per cathode was explored as another method to improve the efficiency of electroosmosis in dewatering and strengthening soil. The results from the designed laboratory experiments confirmed the benefits of increasing the number of anodes or adding positively charged SiO₂@Al₂O₃ core–shell NPs, in increasing the dewatering rate and improving the cohesion, internal friction angle, and microstructure of the treated soil (Lake Silt). The finite element method based simulation results agreed well with the experimental observations and suggested that the NPs can promote the water migration under an electric field.