Abstract:In order to obtain frost heave and thawing settlement of frozen soils behavior, an underground connected aisle was studied through the model test based on similarity theory. The results indicate that, the soil temperature firstly decreases rapidly, then increases and maintains 0℃ for a while, at last continues to slowly rise to room temperature in the whole process. The soil pressure value goes up firstly and then goes down, and that of vertical pressure increases exponentially with the increasing of depth, meanwhile the distance from the freezing tube is more closer, the horizontal pressure is more bigger. Contrast with frost heave displacement, the thawing settlement value is greater, and the vertical displacement is more significant than the horizontal as well. In positive frozen period, the temperature reducing rate becomes slower, the greater depth and closer distance from the freezing hole, the greater decline speed and amplitude come up. Unlike vertical restriction soil always increases, the soil pressure value of unlimited presents a first increasing and then decreasing trend, while the variable rate is bigger with complete restriction situation.