Document Type : Research Paper

Abstract

The Guelph Permeameter technique (GP) is a method for measurement of saturated hydraulic conductivity above the water table which has a strong theoric base and enable the experiments to be done with low cost and high speed. In this method soil's saturated hydraulic conductivity (Kfs) and matric flux potential (Øm) are determined by Richard's two head analysis. In the Homogenous soils the result of the GP is satisfactory, but in the heterogeneous soils a high percentage of Kfs and Øm values will be negative. GP analysis depended greatly on both the constant height of ponded water (H) and steady-state Q value in the hole. Therefore in this experiment the influence of increase or decrease of first and second ponding height (H1 and H2) on producing the negative values, in loam soils was studied. Results showed that the increasing H2 ratio to H1 caused a large number of Kfs and Øm values to be positive, while there was no significant difference between their means.

Keywords

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