Investigation on the hydraulic property variations of saline soil solidified with the synergy of ternary solid waste and cement

Abstract

The hydraulic properties of saline soils play a crucial role in water and salt migration, directly impacting issues like salt-frost heave and corrosion in foundations. This study employs a quaternary mix of fly ash, silica fume, brick powder, and cement to solidify saline soils. Hydraulic performance was evaluated through pressure plate, variable head permeability, contact angle, and disintegration tests, supplemented by Fourier Transform Infrared Spectroscopy (FT-IR) and Scanning Electron Microscopy (SEM) analyses. Results indicate that solidification enhances water retention, though freeze-thaw cycles diminish this effect due to recurring salt-frost heave. Initially, ion exchange reactions increase the permeability, but it decreases over time with higher solidifier content. Water stability improves significantly, with contact angles rising from 14.02° to 89.24° post-solidification. After 28 days of immersion, only slight surface detachment was observed, contrasting with the rapid disintegration of untreated soils. FT-IR and SEM analyses reveal that hydration and pozzolanic products fill pores, reducing porosity and increasing surface roughness, leading to lower surface energy. These findings provide valuable insights into improving the hydraulic properties of saline soils through solidification treatments.