Experiment of impact of freezing-thawing cycle on physico-mechanical properties of loess

By means of freezing-thawing cyclic test with water supplement,the impact of freezing and thawing actions on deformation,water redistribution and dry dense of loess samples was studied.The experimental result showed that repeated freezing and thawing actions would make the water content in samples increased gradually from the bottom to the top.It changed sharply near the interface between frozen and unfrozen areas.At the starting of freeze-thaw cycle,the frost heave of loess samples was stronger.Then the overall deformation became stable,which meant that the deformation induced by frost heave was equal to that inducted by thaw settlement.At the end of freeze-thaw cycle,there was a small settlement in samples,which resulted probably from soil particle rearrangement caused by strong freezing and thawing action.In addition,freezing and thawing actions decreased gradually the dry density of loess samples.The dry density in upper part was larger than that in bottom part.