One-dimensional horizontal infiltration experimen for determining permeability coefficient of loamy sand
HU Shunjun1*, ZHU Hai1,2, CHEN Yongbao1,3
1 State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of
Sciences, Urumqi 830011, China; 2 University of Chinese Academy of Sciences, Beijing 100049, China; 3 Central South Institute of Metallurgical Geology, Yichang 443003, China
One-dimensional horizontal infiltration experiment for determining permeability coefficient of loamy sand
HU Shunjun1*, ZHU Hai1,2, CHEN Yongbao1,3
1 State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of
Sciences, Urumqi 830011, China; 2 University of Chinese Academy of Sciences, Beijing 100049, China; 3 Central South Institute of Metallurgical Geology, Yichang 443003, China
摘要 A knowledge of soil permeability is essential to evaluate hydrologic characteristics of soil, such as
water storage and water movement, and soil permeability coefficient is an important parameter that reflects
soil permeability. In order to confirm the acceptability of the one-dimensional horizontal infiltration method
(one-D method) for simultaneously determining both the saturated and unsaturated permeability
coefficients of loamy sand, we first measured the cumulative infiltration and the wetting front distance
under various infiltration heads through a series of one-dimensional horizontal infiltration experiments, and
then analyzed the relationships of the cumulative horizontal infiltration with the wetting front distance and
the square root of infiltration time. We finally compared the permeability results from Gardner model based
on the one-D method with the results from other two commonly-used methods (i.e., constant head method
and van Genuchten model) to evaluate the acceptability and applicability of the one-D method. The results
showed that there was a robust linear relationship between the cumulative horizontal infiltration and the
wetting front distance, suggesting that it is more appropriate to take the soil moisture content after
infiltration in the entire wetted zone as the average soil moisture content than as the saturated soil moisture
content. The results also showed that there was a robust linear relationship between the cumulative
horizontal infiltration and the square root of infiltration time, suggesting that the Philip infiltration formula
can better reflect the characteristics of cumulative horizontal infiltration under different infiltration heads.
The following two facts indicate that it is feasible to use the one-D method for simultaneously determining
the saturated and unsaturated permeability coefficients of loamy sand. First, the saturated permeability
coefficient (prescribed in the Gardner model) of loamy sand obtained from the one-D method well agreed
with the value obtained from the constant head method. Second, the relationship of unsaturated
permeability coefficient with soil water suction for loamy sand calculated using Gardner model based on the
one-D method was nearly identical with the same relationship calculated using van Genuchten model.
Abstract：
A knowledge of soil permeability is essential to evaluate hydrologic characteristics of soil, such as
water storage and water movement, and soil permeability coefficient is an important parameter that reflects
soil permeability. In order to confirm the acceptability of the one-dimensional horizontal infiltration method
(one-D method) for simultaneously determining both the saturated and unsaturated permeability
coefficients of loamy sand, we first measured the cumulative infiltration and the wetting front distance
under various infiltration heads through a series of one-dimensional horizontal infiltration experiments, and
then analyzed the relationships of the cumulative horizontal infiltration with the wetting front distance and
the square root of infiltration time. We finally compared the permeability results from Gardner model based
on the one-D method with the results from other two commonly-used methods (i.e., constant head method
and van Genuchten model) to evaluate the acceptability and applicability of the one-D method. The results
showed that there was a robust linear relationship between the cumulative horizontal infiltration and the
wetting front distance, suggesting that it is more appropriate to take the soil moisture content after
infiltration in the entire wetted zone as the average soil moisture content than as the saturated soil moisture
content. The results also showed that there was a robust linear relationship between the cumulative
horizontal infiltration and the square root of infiltration time, suggesting that the Philip infiltration formula
can better reflect the characteristics of cumulative horizontal infiltration under different infiltration heads.
The following two facts indicate that it is feasible to use the one-D method for simultaneously determining
the saturated and unsaturated permeability coefficients of loamy sand. First, the saturated permeability
coefficient (prescribed in the Gardner model) of loamy sand obtained from the one-D method well agreed
with the value obtained from the constant head method. Second, the relationship of unsaturated
permeability coefficient with soil water suction for loamy sand calculated using Gardner model based on the
one-D method was nearly identical with the same relationship calculated using van Genuchten model.
2017, Vol. 9 
