Study On The Water And Gas Two-phase Of Unsaturated Soil About The Infiltration

Unsaturated soil is unstable, determination of unsaturated soil infiltration process water and gas two-phase becomes a key test of unsaturated soil. Since the unsaturated soil vapor infiltration process testing technology so far has not been finalized equipment,many scholars is to study the changes of unsaturated soils infiltration wetting front and the calculations of unsaturated soil water and gas two-phase coupling, less research on unsaturated soil vapor infiltration variation and quantitative observations, etc., often ignored the changes of air pressure, and in fact gas phase and water- air interface will affect the unsaturated soil infiltration.Based on the existing non-saturated soil infiltration test device improvement,modification, determination of infiltration process’ s changes of unsaturated soil wetting front and pressure, its unsaturated soil moisture infiltration law of a more in-depth study.The main contents are as follows:(1)Developed a new type of unsaturated soil seepage test device,at the same time,it introduced the test principle, test procedures and equipment operations. And through the device of unsaturated soil water and gas two-phase migration test, measured values of infiltration wetting front and pressure,drawn curve of infiltration wetting front,pressure and time, further analyzed and summarized, elaborated unsaturated soil seepage regularity.(2)Starting from the different soil layers interface stranded phenomenon, we found the interface stranded reason not simply affected by soil matric potential between the particles and pressure, designed different soil structure to test, and retention by observing interface appears isolated, finger flow, preferential flow phenomenon,analyzed and summarized generate conditions and mechanisms for unsaturated soil permeability tests provide a theoretical reference.(3)Of unsaturated soil capillary water penetration for a detailed test, from the soil structure to groundwater evaporation, from the soil to the solute, from the vertical to thehorizontal direction we have carried out specific tests, measuring the value of unsaturated soil wetting front, draw the infiltration curve wetting front and time,elaborated factors and regularity of capillary water penetration.