Experimental study on the influence of initial water saturation on segregation frost-heaving behavior in silty clay columns

The impact of initial water saturation on segregation frost heaving behavior was investigated by conducting 1-dimensional (1-D) soil column freezing tests with a water supply. The test results demonstrated that: (1) A frozen fringe with segregation cracks was observed in all tested soil columns. Water migrated towards the frozen fringe and transformed into segregated ice. After freezing, the total water content in the segregation zone could reach double or triple its initial value. (2) The segregated ice destroyed the soil's initial fabric and enhanced the soil void. The ice saturation in the segregation cracks reached just 0.5. (3) The total frost heave amount, frost heave ratio, segregated ice content, and the segregation crack width were all linearly related to the initial water saturation. (4) Frost heave was significant in silty clay with an initial water saturation greater than 0.53. The results reveal initial water saturation to be the primary factor controlling frost heave in silty clay and should thus be given appropriate attention in the design of frozen soil engineering.