Characteristics and calculation model of phreatic evaporation of sand-layered soil

Phreatic evaporation characteristic of sand-layered soil with a shallow water table was analyzed according to laboratory experiments. Results show that the sand layer has positive and negative effect on the water evaporation. At the same soil layer, the phreatic evaporation decreases with the increase of sand positions and the decrease of sand particle sizes. Taking relative sand position and sand particle size as quantitative indices, correct model of steady phreatic evaporation with different sand positions and sand particle sizes was established. Parameters test of steady phreatic evaporation model was analyzed. The research supplies a new method for quantitative study of steady phreatic evaporation of sand-layer soil.