Abstract
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.
Keywords
ConductivityHydraulic conductivityMoistureHysteresisComputationThermodynamicsWater contentMathematicsElectrical resistivity and conductivityLoop (graph theory)Soil scienceMaterials scienceSoil waterChemistryPhysicsEnvironmental scienceGeotechnical engineeringGeologyCondensed matter physicsComposite material
Affiliated Institutions
Related Publications
Calculation of Hydraulic Conductivity: A further Evaluation of some Predictive Methods
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 ...
Comparison of measured and calculated hydraulic conductivities of unsaturated soils
Three methods to calculate the unsaturated conductivity of soil from its moisture characteristic were tested. Calculated values were compared with direct measurements of conduct...
Hydraulic Conductivity Evaluation of the Soil Profile from Soil Water Retention Relations
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 new model for predicting the hydraulic conductivity of unsaturated porous media
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...
Soil Capillary Conductivity: Comparison of Measured and Calculated Values
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...
Publication Info
- Year
- 1968
- Type
- article
- Volume
- 32
- Issue
- 6
- Pages
- 760-765
- Citations
- 247
- Access
- Closed
External Links
Social Impact
Altmetric
PlumX Metrics
Social media, news, blog, policy document mentions
Citation Metrics
247
OpenAlex
7
Influential
157
CrossRef
Cite This
R. J. Kunze,
G. Uehara,
Katharine E. Graham
(1968).
Factors Important in the Calculation of Hydraulic Conductivity.
Soil Science Society of America Journal
, 32
(6)
, 760-765.
https://doi.org/10.2136/sssaj1968.03615995003200060020x
Identifiers
- DOI
- 10.2136/sssaj1968.03615995003200060020x