Computation of local permeability in gap-graded granular soils

TL;DR

This paper introduces semi-analytical methods to estimate local permeability in granular soils using indirect porosity measurements and modified equations, providing results comparable to experimental data within acceptable deviation.

Contribution

It presents novel semi-analytical techniques that incorporate particle migration effects to accurately estimate local permeability in granular soils.

Findings

Proposed methods yield permeability estimates within one order of magnitude of experimental results.

The methods effectively incorporate particle migration effects into permeability calculations.

Results demonstrate practical applicability for soil permeability assessment.

Abstract

This paper proposes semi-analytical methods to obtain the local permeability for granular soils based on indirect measurements of the local porosity profile in a large coaxial cell permeameter using spatial time-domain reflectometry. The porosity profile is used to obtain the local permeability using the modified Kozeny-Carman and Katz-Thompson equations, which incorporated an effective particle diameter that accounted for particle migration within the permeameter. The profiles of the local permeability obtained from the proposed methods are compared with experimentally obtained permeability distributions using pressure measurements and flow rate. The permeabilities obtained with the proposed methods are comparable with the experimentally obtained permeabilities and are within one order of magnitude deviation, which is an acceptable range for practical applications.