Influence of anions on the geotechnical properties of soils treated with hydraulic binders: Individual and coupling effects

The treatment of soils with hydraulic binders improves their physical and mechanical characteristics, allowing the soils to be reused in several geotechnical applications such as road construction. The aim of this research study is to assess the influence of sulfate, chloride, nitrate and phosphate ions, introduced as CaSO4·2H2O, NaCl, NH4NO3 and KH2PO4, on the physical and mechanical properties of a treated soil under accelerated curing conditions. Then, the influence of sulfate ions is determined in the presence of another anion. ing the influence of each anion on the soil considered, only phosphate ions have a deleterious effect on the stabilization at concentrations between 3 and 10 g kg−1 of dry soil. The sulfate ions induce an important volumetric swelling at 10 g kg−1. r, the combination of one anion with sulfate ion induces important disturbances on both volumetric swelling and indirect tensile strength: these interactions must be taken into account in the determination of the stabilization of disruptive parameters.