Abstract: The physicochemical properties of disturbed soil sample before and after treatment by EN-1 ionic soil stabilizer (ISS) were researched by tests. AAS (atomic absorption) and FITR (infrared spectrum) technique were utilized to analyze the composition of ISS. The disturbed soil samples from the sliding zone of loess landslide was taken as research object. Test results showed that the cation exchange capacity, exchangeable cation capacity, plasticity index and specific surface area of the ISS-treated soil sample decreased to the minimum when the mixture ratio (ISS to water volume) of ISS solution is identified as 1∶150. Furthermore, the mechanism of ISS acting on the soil can be explained as follows: the soil sample’s sensitivity to water was weakened and the soil stability against water was improved through complex surface physicochemical reactions including moistening, cation exchange, absorption and coverage. Since the mechanical property of clay is related with its water sensitivity and stability, to improve the water sensitivity and stability of clay through ISS offers a new thinking for the modification of landslide soil and the landslide treatment.

Key words: EN-1 ionic soil stabilizer, sliding zone soil, plasticity index, physicochemical properties