Study On Infiltration Into Soils Interbedded With Different Media

This experiment adopts the method of indoor soil column simulated infiltration,for three kinds of material(gangue,sand,fly ash)on different bulk density(1.2 g·cm-3,1.3 g·cm-3 and 1.4 g·cm-3),different material layer location(upper of Soil column,middle of soil column and bottom of soil column)and different thickness of medium layer(4 cm,8 cm,12 cm)a total of 81 different treatment,three kinds of medium and soil layers respectively filled in transparent PVC pipe,concrete setup:soil column containing gangue,soil column containing sand,soil column containing fly ash,observing the Change rule of soil moisture accumulation infiltration curve,The total water infiltration aresults nd Infiltration duration.Researching the layered soil containing medium water infiltration process.The showed that:(1)For layered soil containing gangue,under the condition of the coal gangue layer location and thickness of the same,soil moisture cumulative infiltration amount along with the increase of bulk density showed a trend of decrease gradually,sort for:1.4 g·cm-3<1.3 g·cm-3<1.2 g·cm-3;the cumulative infiltration volume with the change of coal thickness under law:When coal gangue is located in the upper layer,the greater the thickness,the greater the cumulative infiltration amount;When the gangue layer is located in the middle,the thickness of 8 cm cumulative infiltration volume is minimal,the cumulative infiltration quantity disparity is not obvious Between 4cm and 12cm;When coal gangue is located in the bottom,The influence of thickness on cumulative infiltration curve is not obvious.With the same density and thickness of gangue layer,the cumulative infiltration volume change with gangue layer position has great changes.According to the order from large to small was the upper>the lower layer>the middle.(2)For layered soil containing sand,with the same of the position and thickness of sand layer the influence of bulk density of soil water infiltration process.The influence of density on soil water infiltration process is great.When the sand layer position is located in the upper and the bottom,the accumulation of soil water infiltration quantity is inversely proportional with the size of the bulk density;In the same situation what bulk density and the sand layer position,when sand layer is located in the upper soil moisture accumulation infiltration amount is proportional to the thickness of sand layer;when the sand layer is located in the middle,the cumulative infiltration amount when thickness of 8 cm less than thickness is 4 cm and 12 cm;When the sand layer is located in the bottom,the cumulative infiltration amount less than the homogeneous soil.According to its decreasing amplitude of order:4cm(23.96%)>8cm(21.60%)>12cm(16.50%);Under the condition of the same density and thickness of the dielectric layer,when the upper sand layer in the soil column,the existence of sand layer is advantageous to the soil water infiltration,sand layer is located in the middle and bottom,due to the effect of permeability of the sand layer,infiltration volume is small.(3)For layered soil containing fly ash,under the condition of the fly ash layer location and thickness of the same.When the density is small,cumulative infiltration amount along with the bulk density changed little,the greater of bulk density,infiltration amount decreases the more obvious;In the same situation what bulk density and the fly ash layer position,when fly ash layer is located in the upper,in the same infiltration time,cumulative infiltration volume of the thickness of 8cm is the largest,the second is 4cm,cumulative infiltration amount minimum is the treatment with the 12cm thick,but because the thickness is 4cm and 12cm infiltration lasted more than 8cm length,in terms of total infiltration,cumulative infiltration volume with the thickness of 8cm is minimal,the rest of the difference between the two groups is not obvious;When fly ash layer is located in the middle,the thickness of the impact on the cumulative infiltration amount in bulk density increases when presents the obvious regularity.When the bulk density is 1.4g·cm-3,cumulative infiltration amount ordering:4cm>12cm>8cm;When fly ash is located in the bottom,the influence of thickness on cumulative infiltration amount is not obvious.Under the condition of the invariant on fly ash layer thickness and bulk density,cumulative infiltration amount ordering:upper of soil column>bottom of soil column>middle of soil column.(4)Through the analysis of the IBM SPSS Statistics software 22.0,medium thickness of three layered medium soil of the performance of soil water infiltration duration is not significant,and the medium layer location and density on its infiltration duration is very significant.(5)Optimal containing gangue layered soil infiltration model is the general formula,optimal containing sand layered soil infiltration model is Kostiakov model,compared with slightly less appropriate formula;Optimal containing fly ash layered soil infiltration model is the general formula.