应用保水剂对黄绵土水分特征的影响研究

Investigation on Loess Soil Water Characteristic as Influenced by SAPs

为了探求保水剂在黄绵土中的作用规律,选取了三种国内外不同的保水剂,利用离心机法测定了不同浓度保水剂作用下黄绵土水分特征曲线。从保水剂种类、浓度对土壤含水量的影响、不同保水剂对土壤吸释水及效率的影响、保水剂品种比选等方面系统进行了研究。结果表明：（1）浓度对黄绵土土壤饱和含水率的影响显著,且0.75%是明显的分界线。（2）土壤含水量随保水剂浓度增加而增大,随着土壤水吸力的增大而减小,且这种改变作用在低吸力段（0.01~0.8 MPa）明显高于高吸力段（0.8~1.5 MPa）,在0.01~0.05 MPa之间尤其显著。（3）保水剂在黄绵土中的应用效果来看,钾-聚丙烯酸酯-聚丙烯酰胺共聚物类保水剂最好,其次是聚丙烯酸盐类保水剂,再次是丙烯酰胺与丙烯酸钾共聚物类保水剂,主要表现在提高土壤有效水分吸收效率和吸收数量两个方面。

In order to search the rule of SAPs＇ activity on loess soil,centrifuge method was used to measure soil water characteristic curve on different concentration of SAPs.Influence of soil moisture on different SAPs with various concentrations,influence of soil absorbing capacity and efficiency on different SAPs,and comparison of the SAPs were analyzed systematically.The results show that：（1） Concentration had obvious effects on soil saturation moisture,and 0.75% was a boundary;（2） Soil moisture rised with the increase of SAPs＇ concentration,and declined with the increase of soil potential.The effect in low-suction period（0.01～0.8 MPa） was stronger than that of high-suction period（0.8～1.5 MPa）,especially in 0.01～0.05 MPa;（3） From the experimental results： STOCKOSORBTM SAP was the best,and AQUASORBTM SAP was the second,and ACRYLATE SAP was the worst.The strongpoint of STOCKOSORBTM SAP was embodied in two aspects： the amount and efficiency of absorbing available water.