Abstract |
The hydraulic functions, i.e., hydraulic conductivity-water content and pressure head-water content relationships, were measured in an unsteady state flow situation on a column of sand using gamma absorption for water content measurements and pressure transducer tensiometry for pressure head measurements. Subsequently, the same flow column was subjected to a boundary condition that caused drainage and rewetting of the column. Measurements of pressure head, hydraulic head and water content versus time were made at various positions. These data were compared with the predictions from soil water flow theory which included the effects of hysteresis in the water content-pressure head relationship. Measured and predicted pressure head-time curves were in reasonable agreement, but measured and predicted water content-time curves were not always in good agreement. (Author) |