JCE_V5_N4_RP3 Determination of Water Retention and Unsaturated Hydraulic Conductivity of Brahmaputra Sand Malaya C. Sreedeep S. Journal on Civil Engineering 2249 - 0779 5 4 14 20 Sandy Soil, Soil Suction, Volumetric Water Content, Water Retention Characteristic, Unsaturated Soil Hydraulic Conductivity, Measurement, Estimation 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 (k ) is a challenging task and it requires a costly and skilled experimentation. Therefore, the normal u practice is to estimate k from water retention characteristics. Water Retention Characteristic (designated as WRC) u includes the development of a graphical relationship between suction and water content (gravimetric or volumetric). This indicates that the accuracy of k is very much dependent on the unambiguous determination of WRC. In this study, a u 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 k of the soil has been estimated based u on the WRC obtained. The main purpose of this investigation is to understand the extent of influence of different WRC measurement procedures on k estimation. The study indicates that the measurement procedures have moderate u influence on uniqueness of WRC of Brahmaputra sand and hence the estimated k. September - November 2015 Copyright © 2015 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Archives.aspx?JournalIssueId=698