保水剂对红砂岩土壤持水特性的影响

为了探究红砂岩土壤中施用保水剂对其持水特性所造成的影响,在红砂岩土壤中按保水剂质量比为0,0.25‰,0.50‰,1.00‰,2.00‰施用保水剂的条件下,测定了不同比例保水剂措施下的土壤水分特征曲线、土壤入渗过程和土壤水分蒸发过程,并用二次曲线求得最佳施用量.研究结果表明,随着保水剂施用量增加,饱和含水量θ_s呈增大的趋势,而残余含水量θ_r、进气值相关参数α和开关系数n总体上呈现先增大后减小的趋势,保水剂主要增加土壤重力水.施用保水剂抑制了土壤的入渗性能,降低了水分垂直入渗率,延长了入渗持续时间,减缓了土壤水分蒸发速率.综合考虑保水效果和施用量,红砂岩土壤最佳保水剂施用量范围为0.5‰~1.0‰.

Effect of super absorbent polymers on water-holding characteristics of red sandstone soil

In order to explore the effect of applying super absorbent polymers(SAP)on water retention characteristics of red sandstone soil, under condition that SAP at mass ratios of 0, 0.25‰, 0.50‰, 1.00‰, 2.00‰ was mixed to red sandstone soil. The soil water characteristic curve, the soil infiltration process and the soil water moisture evaporation process under different ratios of SAP mea-sures were measured. Meanwhile, the quadratic curve was used to determine the optimal application amount. The results show that the saturated water content(θ_s)has an increasing trend as the use amount of SAP increases, and the values of residual water content(θ_r), intake value related parameters(α), and shape factor(n)generally increase first and then decreasing. The SAP mainly increases soil gravity water. Thus, the application of SAP inhibits the infiltration performance of soil, reduces the vertical infiltration rate of water, prolonges the duration of infiltration, and the soil water evaporation retarded. Comprehensively considering the water retention effect and application amount, the optimum SAP application range for red sandstone soil is maintained at 0.5‰-1.0‰.