Abstract：Freezing-thawing changes the mechanical properties of soil through changing its structure. In this paper，the saturated Lanzhou loess and Tianjin silty clay are taken as study objects. After all the two soils experience a freezing-thawing cycle，soil mechanics tests and SEM quantitative analysis are performed. After comparatively analyzing the data of soils before and after freezing-thawing，it is found that both mechanical properties and microstructure of the two soils are changed by freezing-thawing. Moreover，the change of mechanical properties can be explained by the change of microstructure to some extent.
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2003, Vol. 22 
