Strength and microstructure of salt-rich soft soil improved by cement

Based on the results of unconfined compression tests of salt-rich soft soil improved by cement, the effects of the variation of Mg²⁺, Cl^-, SO₄^2- content in soft soil on the strength of cemented salt-rich soil were studied, and the law of the strength changing with these ion contents was also explored. X-ray diffraction and scanning electronic microscopy (SEM) were used to analyze the microstructural characteristics of soil-cement with different ion contents. The relationship between the strength and the microstructure of soil-cement was investigated in this paper. Research results show that a closely linear correlation exists between the strength and the total amount of C-S-H and C-A-H content in soil-cement, The change of Mg²⁺, Cl^-, SO₄^2- content in soft soil results in the difference of the microstructure of salt-rich soil improved by cement, high contents of Mg²⁺, Cl^-, SO₄^2- in soft soil have negative effects on the strenght of soil-cement. Attention should be paid to the influence of high salt content on the strength of soil-cement in engineering.