【摘要】 <正> 易溶盐在土中的存在及其在土冻结过程中的重新分布,对冻土物理化学性质和力学性质及土的冻结过程有重要影响。泰斯等(Tice,et al.)用兰州黄土和阿拉斯加粉土等作对比试验,证明在颗粒成分大致相同的情况下,冻结盐渍土中未冻水含量高于非盐渍土中未冻水含量。张伯伦(1983)的试验表明,对同一种土,增加其易溶盐含量可以减小土的冻胀量、总含冰量及冰透镜体的体积。至于冻结过程中盐分迁移的方向,可有不同情况。邱国庆等的实验表明,在水溶液单向冻结时,盐分向未冻溶液迁移,溶液原始浓度越大、冻结速度越大,则盐分的相对迁移量越小。奥斯托坎等(Oster-更多还原

【Abstract】 Sixteen specimens made of Morin Clay with a saturation percentage of 86% were subjected to freezing tests in open system fed by distilled water, NaCl solution, CaCl2 solution and Na2SO4 solution respectively.Before freezing test specimens were homogeneous in water content but heterogeneous in chemical composition with a vertical concentration gradient.After freezing test both water content and the dominant-anion content in frozen part of the soil samples increase;this means that not only moisture but also ions were migrating toward the freezing zone during tests. Empirical equations show that there are exponential relations of the increase ratio (Y1)of dominant anions, water content migration ratio ( Y2 ) and frost heaving ratio ( Y3 ) to the freezing rate(X1 ) and to the original content (X2)of dominant anion.An increase in Y1 will lower the Y1,Y2 and Y3 in NaCl and Na2SO4 cases but have less effect on Y1 in CaCl2 case.When specimens were fed by CaCl2 or NaCl solution,an increasr in X2 will lower the Y1,while in Na2SO4 case Y1 will increase with X2. Also Yi and Y3 will decrease with X2 increasing.更多还原