Abstract The calculation of hydraulic conductivity by a modified Millington‐Quirk method with a matching factor gave conductivity values closely approximating experimentally measured values. The technique requires knowledge of the moisture characteristic and the saturated conductivity. A number of factors that affect the calculated values and improve the computational results were investigated. Calculated conductivity values decreased with an increasing number of pressure classes at low moisture contents. For all soils tested the calculated conductivities were less than the experimental values at the terminal point of the moisture characteristic. This discrepancy was partially corrected by a small change in the Millington‐Quirk equation, by extending the moisture characteristics to higher suction values, and by reducing the number of pressure classes to approximately 10. A matching factor, the ratio of measured over calculated saturated conductivity, was found necessary for obtaining the best fit of calculated and measured data. Two conductivity functions calculated separately from each moisture characteristic forming a hysteresis loop, converged as the hysteresis loop was translated to higher tensions. All computations were done by computer.
Abstract A computational method based on the pore‐interaction model of Marshall was shown to compare favorably with modified methods of Millington and Quirk and of Marshall for ...
Three methods to calculate the unsaturated conductivity of soil from its moisture characteristic were tested. Calculated values were compared with direct measurements of conduct...
Abstract Evaluation of the water content‐suction relation applicable to field soil horizons that differ widely in texture was considered. Except for coarse‐textured, organic mat...
A simple analytic model is proposed which predicts the unsaturated hydraulic conductivity curves by using the moisture content‐capillary head curve and the measured value of the...
Abstract Capillary conductivities were measured for two loess soils and two glacial till soils at four depths and at five values of water suction, up to and including 100 cm. of...
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