Durability of Soft Soil Treated with Soda Residue and Ground Granulated Blast Furnace Slag in a Soaking Environment

This study investigates the effect of soaking conditions on the durability of soft soil treated with soda residue and ground granulated blast furnace slag. Specimens were cured for up to 60 days and soaked in solutions for up to 28 days. Tap water (T), NaCl (N), MgSO4 (M), and NaCl+MgSO4 (N-M) were selected as soaking solutions. The results indicate that the stabilized soil was durable in tap water even cured for two days. When soaked in T or N environment, the strength of the specimens increased with soaking period due to dense structure and hydrated gel filling between matrix. The strength of the specimens soaked in solutions was slightly higher than that in tap water. However it decreased slightly after soaking for 28 days in M or N-M environment due to looseness at the ends of the specimens and formation of ettringite cluster. The effects of reinforcing and filling-in of hydration products, including calcium silicate hydrates, ettringite, calcium chloroaluminate hydrates and calcium chloride hydroxide hydrate, contributed to an improvement in strength and durability.