Solidifying saline-alkali soil with inorganic materials in a region of seasonal frost: Experiment and evaluation

Nine solidification approaches utilizing two inorganic materials were employed to mitigate the adverse impact of saline-alkali soil on engineering foundations and address the damage caused by freeze-thaw cycles in the Songnen Plain. The impact of inorganic material content on the shear strength of saline-alkali soil and its resistance to freeze-thaw cycles was examined. Additionally, the effectiveness of the solidification scheme was assessed concisely using the Criteria Importance Though Intercrieria Correlation - VlseKriterijumska Optimizcija I Kaompromisno Resenje (CRITIC-VIKOR) model. The findings demonstrate that both lime and fly ash enhance the shear strength of saline-alkali soil, with lime exhibiting superior effectiveness compared to fly ash. Lime induces strain-softening in the stress-strain curve of the soil. At the same time, fly ash significantly improves its resistance to freeze-thaw damage. The combined addition of lime and fly ash strikes an optimal balance between shear strength and freeze-thaw resistance. Considering mechanical performance, freeze-thaw resistance, and economic factors, scheme VII (12% lime content and 0% fly ash content) was selected based on the CRITICVIKOR model as the foundation for solidifying saline-alkali soil in regions of seasonal frost action.