温度影响下的非饱和黄土水分迁移问题探讨

对非饱和黄土土样的实验结果揭示出，对于初始含水量均布的土样，在两端施加温差后，冷端的含水量增大，热端含水量减小。在温度差作用下，温度差越大，土体密度越小，水分迁移特征越明显，土样两端含水量差越大。当初始含水量较大和较小时，温度差引起的含水量差均较小；当初始含水量适中时，温度差引起的含水量差值较大。基于实验结果，考虑含水量和密度的影响，得到温度梯度引起含水量梯度的表述关系式，计算和实测结果验证了该表述式的可靠性。据此得到了考虑温度影响的非饱和黄土水势的表述式，该式考虑了土体密度、温度梯度、含水量和含水量梯度对水势的综合影响，对实验土样的计算结果反映了水分的稳态分布。

Moisture migration in unsaturated loess considering temperature effect

Moisture migration in unsaturated loess considering temperature effect is studied by test. The test data show that the more is the temperature gradient in soil, and the less is the soil density, the more is the soil water content gradient resulting from moisture migration. If the soil primary water content is gradually added from very little value,the value of water content gradient resulted from temperature gradient first is lower,then bigger and finally lower. After analyzing the test data, taking the soil density and moisture content into account, the formula is obtained to determine the water content gradient resulting from the temperature gradient. The test and calculated data verify the reliability of the formula. And the method is got to determine the hydraulic head of unsaturated soil under thermal gradient, in which the temperature gradient, soil density, soil water content and water content gradient all are taken into account.