为研究非饱和黄土对水蒸气的吸附特性，采用蒸汽平衡法开展不同湿度环境下的等温吸附试验，分析水蒸气在非饱和黄土表面的吸附行为，并探讨温度、矿物成分及含量、干密度对土体吸附性能的影响。结果表明：非饱和黄土水蒸气吸附量随相对湿度的增加而增加，整个过程包含了单层吸附、多层吸附和毛细凝聚3个阶段，且GAB模型可以用来描述非饱和黄土的水蒸气吸附过程；水蒸气吸附量与温度之间存在明显的负相关关系，相对湿度恒定，水蒸气吸附量随温度的升高而降低；非饱和黄土的水蒸气吸附与矿物组成密切相关，黏土矿物含量直接影响其水蒸气吸附能力；此外，干密度对水蒸气吸附量的影响可分为两个阶段，在相对湿度RH<80%时，水蒸气吸附量随干密度的增大而增大，直到进入毛细凝聚阶段，随着干密度的增大，水蒸气吸附量不再增大反而有所降低。

In order to study the adsorption characteristics of water vapor on unsaturated loess, isothermal adsorption experiments under different humidity conditions were carried out by vapor equilibrium method. The adsorption behavior of water vapor on the surface of unsaturated loesswas analyzed, and the effects of temperature, mineral composition and content, dry density on the adsorption property of soil were discussed. The experimental results show that the water vapor adsorption capacity of unsaturated loess increases with the increase of relative humidity, and the entire process consists of three stages: monolayer adsorption, multilayer adsorption and capillary condensation. The GAB model can describe the water vapor adsorption process of unsaturated loess. There is a significant negative correlation between water vapor adsorption capacity and temperature. When the relative humidity is constant, the adsorption capacity of water vapor decreases with the increase of temperature. Water vapor adsorption of unsaturated loess is closely related to mineral composition, and clay mineral content directly affects its water vapor adsorption capacity. In addition, the effect of dry density on water vapor adsorption capacity can be divided into two stages. When the relative humidity RH<80%, water vapor adsorption capacity increases with the increase of dry density. For capillary condensation stage, with the increase of dry density, the amount of water vapor adsorption no longer increases but decreases.

TU444

国家自然科学基金（41662017）