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首先自制了冻结作用导致水分迁移的试验装置,采用未设置格栅试验装置得到了液态水和气态水混合迁移结果,采用设置格栅试验装置得到了阻断液态水迁移通道情况下水分迁移结果.试验结果表明,土样密度、含水量、时间对冻结作用导致的水分迁移进程均有影响.冻结过程冻结锋面的推进使冻结区域含水量明显增大,未冻结区域含水量明显减小,冻结锋面处含水量增加最大.相对于未冻结区域水分迁移进程,水分向冻结锋面的迁移是比较缓慢的.干密度较小土样冻结区域含水量增加值小于干密度较大土样,干密度大,冻结锋面处的含水量增量相对较少.初始含水量越大,冻结锋面土体含水量增加值越大,并形成冰层.随着时间增加,冻结锋面处的含水量增加,但后期含水量随时间的增加值明显小于前期,在冻结锋面冰层形成初期,未冻结区域水分向冻结锋面迁移量大,冰层形成以后水分迁移量小.当土样初始含水量比较小时,设置格栅阻断液态水通道对冻结作用导致的水分迁移进程影响不大,向冻结锋面迁移水量主要来源于气态水迁移.当土样初始含水量比较大时,和混合迁移试验结果相比较,设置格栅阻断液态水迁移通道后向冻结锋面迁移水量明显减小.“,”The test equipment is designed for measuring moisture migration in freezing unsaturated loess,using the equipment with no grill the liquid water and vapor water mixed migration results is obtained,and using the equipment with grill the moisture migration results is obtained in situation the liquid water migration channel has been blocked.Freezing the frontal advancement causes water content to increase obviously in frozen region,and freezing frontal water content increases in a big way.Opposite to moisture migration in warm region,the moisture migration to the freeze frontal area is quite slow.The increase in water content frozen region of small density loess is smaller than with the big density loess,and the freeze frontal water content increase in big density loess is relatively smaller than in small density loess.Whese initial water content is bigger,the freeze frontal water content increase in value is bigger,so is the ice layer existence.The freeze frontal water content increase along with the time in later period is smaller than earlier period.When the initial water content in loess is quite small,the mixed migration results and the establishment grill water migration results is nearly the same.This indicates that the grill blocking the liquid water migration pass has no advancement influence on moisture migration in freezing loess.When the initial water content is quite big,in comparison with the mixed migration test result,the grill is established to block the liquid water migration channel backward freeze frontal area migration water volume from reducing obviously.