Determination of Water Retention and Unsaturated Hydraulic Conductivity of Brahmaputra Sand

Vol. 5  Issue 4
Year: 2015
Issue: Sep-Nov
Title: Determination of Water Retention and Unsaturated Hydraulic Conductivity of Brahmaputra Sand
Author Name: Malaya C and Sreedeep S
Synopsis:

Unsaturated soils with hydraulic properties such as water retention and hydraulic conductivity are considered to be the most crucial parameters for modeling flow process in unsaturated soils. Experimental determination of unsaturated hydraulic conductivity (ku ) is a challenging task and it requires a costly and skilled experimentation. Therefore, the normal practice is to estimate ku from water retention characteristics. Water Retention Characteristic (designated as WRC) includes the development of a graphical relationship between suction and water content (gravimetric or volumetric). This indicates that the accuracy of ku is very much dependent on the unambiguous determination of WRC. In this study, a tensiometer and volumetric water content probe have been used to measure soil suction and volumetric water content, respectively of a local sand by using two different measurement procedures. The ku of the soil has been estimated based on the WRC obtained. The main purpose of this investigation is to understand the extent of influence of different WRC measurement procedures on kuestimation. The study indicates that the measurement procedures have moderate influence on uniqueness of WRC of Brahmaputra sand and hence the estimated ku.