Abstract: The consistency in position and time of segregation ice in frozen soils is obtained by use of dynamic photograph and image processing in continuously freezing experiments of one-dimensional open system with different temperature gradients. According to the binarization images of frozen soils, the initiation time, position, thickness and evolving rules of segregation ice can be obtained quantitatively. The thickness of segregation ice obtained from the image analysis is consistent with the frost heave tested by displacement transducer. Three phases of evolving process in the ice segregation can be divided according to the results of the image processing: the early freezing, the growth of thin and discontinuous segregation ice and the final ice lens. There is nearly a linear relationship between the initiation time of the final ice lens and the temperature gradient in continuously freezing experiments. The initiation time of the final ice lens will move up with the increase of the temperature gradient.