摘要
为了研究夹砂层对入渗强度、湿润锋行进和沿程土壤含水率变化的影响,进行了室内层状夹砂土柱一维薄层积水入渗试验和相应情况下均质土柱的对照试验。结果表明,当湿润锋到达夹砂层上界面后,层状夹砂土柱的入渗过程与均质土入渗表现出明显不同。在湿润峰穿过夹砂层上界面时入渗率有较大波动,且最终进入稳渗阶段,其稳渗率明显小于同时刻均质土柱入渗率;当湿润锋穿过夹砂层后,夹砂层内的土壤含水率明显小于其饱和含水率。根据试验和分析,建立了针对层状夹砂土入渗的S-Green-Ampt模型,该模型可以较准确地反映层状夹砂土柱积水入渗的机理和更好地模拟其入渗过程。
Infiltration experiment on soil columns of homogeneous loam and loam with a sand interlayer under ponding conditions were conducted in laboratory. The influence of sand interlayer on infiltration rate,wetting front advancement and the variation of water content along the soil profile was monitored and analyzed. After the wetting front reached the upper interface of the sand interlayer,the infiltration process of the loam with sand interlayer was distinctly different from that of the homogeneous soil,and the infiltration rate varied greatly. Finally a steady infiltration stage reached,and the steady infiltration rate was smaller than that of the homogenous soil. When the wetting front passed the sand interlayer,water content inside this coarse interlayer was less than the saturated water content. According to the observation and analysis,S-Green-Ampt model was established to describe the infiltration process with coarser interlayer. This model can more accurately reflect the mechanism of infiltration into layered soils and better describe the infiltration process of soil with sand interlayer.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2010年第11期61-67,共7页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家自然科学基金项目(50979105)
教育部新世纪优秀人才支持计划项目(07-0814)
北京市科技计划课题(D090409004009004)
