The Hydraulic conductivity (K) of soil, is an important parameter that is used to predict the movement of water and the dissolved contaminants, if any, through it. It can be determined through different in-situ and lab methods; however, it can also be determined easily, using the PSD models or empirical equations developed for this purpose. These equations specifically utilize the particle size distribution (PSD) data of the soil, as movement of water, and hence the hydraulic conductivity depends upon the types and sizes of the soil particles. Most of these equations have been developed for the coarse-grained soil only like the sand and gravel, and some of them only consider the fine-textured soil. In actual condition, soil is not present only as the sand or gravel or as fine-textured only but is the combination of three important particles, which are sand, silt, and clay, due to which the permeability of the soil is affected. This research work is based on the hypothesis that the formulas developed for the estimation of K, the hydraulic conductivity of the soil, may not work properly due to the presence of other particles. For this, different empirical models were considered for only four textural classes of the soil i.e., sand, loamy sand, sandy loam, and silt loam. It was found that as the number of fine particles increases in the sand the formulas do not give a good estimate of the K value.
Nazia Arfeen Taj Ali Khan Evaluation of PSD Models for the Estimation of Hydraulic Conductivity for Different Soil Textural C International Journal of Engineering Works Vol. 7 Issue 10 PP. 338-341 October 2020 https://doi.org/10.34259/ijew.20.710338341.
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