黄土增湿过程是黄土持水特性与增湿变形特性相互影响的过程。已有的土水特征曲线模型主要描述土体的含水状态与吸力的相关关系，无法全面反映增湿过程中黄土的持水特性与变形特性。因此在固结仪上开展了新疆原状黄土的分级增湿试验研究，试验中引入能够全面反映土体含水状态和变形情况的“增湿水平”这一变量，并用增湿水平和吸力表征黄土土水特征曲线模型。结果表明：各竖向压力作用下增湿过程中，半常用对数坐标系下原状黄土增湿水平与吸力关系曲线形状相似，均明显的分为初期平缓段和陡降段两个阶段；竖向压力对增湿水平与吸力关系曲线的影响主要体现在初始吸力与陡降段斜率的不同，可以归一化为幂函数形式；为此建立了以增湿水平和吸力表征的土水特征曲线模型。并将该模型用于其他地区黄土，验证了所建模型适用于原状黄土的初始含水率和吸力状态、不同初始含水率的压缩状态，以及重塑黄土在压力作用下的增湿变形状态。

In the humidification process,the water retention characteristics and the humidification deformation characteristics of original loess interact with each other. The existing soilwater characteristic curve model mainly describes the correlation between the watercontaining state and the suction force.These models cannot fully reflect the water retention characteristics and the deformation characteristics of loess during humidification process.Therefore,the graded humidification tests were carried out in Xinjiang undisturbed loess using consolidation apparatus.Then a soil-water characteristic curve study,characterized by moistening level and suction was conducted.The test results showed that curve shapes of moistening level versus suction during humidification process under vertical pressure were alike in semi-common logarithmic coordinate system,which possessed two sections:flat section and steep drop section.The influence of vertical pressure was manifested mainly by the difference between initial suction force and slopes in the section of steep drop. Relationship curves of moistening level and suction under different vertical stress can be regressed as a power function.On basis of the test results, the soil-water characteristic curve model considered by moistening level and suction was proposed.Finally,the model was applied in the other areas of loess.The results validated the applicability of the model to compression state or unpressurized condition state of original loess with different initial moisture content as well as humidification process of remolded loess in compression state.

国家重点研发计划课题(2017YFC0804607);流域水循环模拟与调控国家重点实验室项目(SKL2018ZY09)