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| DENSITY-SATURATION-DEPENDENT AIR-WATER PERMEABILITY FUNCTION OF UNSATURATED LOESS |
(1. Institute of Geotechnical Engineering，Xi¢an University of Technology，Xi¢an，Shaanxi 710048，China；
2. Yellow River Engineering Consulting Co.，Ltd.，Zhengzhou，Henan 450003，China) |
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Abstract The coefficient of permeability of unsaturated soil is a key parameter in performing seepage analysis in saturated/unsaturated soils. However，both the degree of saturation and the dry density influence the coefficient of permeability of unsaturated soil. A series of experiments are performed by using the improved measurement apparatus under different infiltration steps and various initial dry densities of unsaturated remoulded loess specimens. According to the results，the relationships among degree of saturation，dry density，coefficients of air and water permeability are analyzed. A new density-saturation-dependent air-water permeability function is put forward based on the above relationships；and it can not only determine the coefficient of water permeability but also quantitatively describe the mutual influence of movement of both air and water in the void of unsaturated soil. Finally，the new experiment is provided to verify the proposed permeability function. It is shown that the predicted curves are in good accordance with the experimental data.
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Received: 06 April 2010
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2010, Vol. 29 
