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Characterization of Miller‐Similar Silica Sands for Laboratory Hydrologic Studies
Author(s) -
Schroth M. H.,
Istok J. D.,
Ahearn S. J.,
Selker J. S.
Publication year - 1996
Publication title -
soil science society of america journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.836
H-Index - 168
eISSN - 1435-0661
pISSN - 0361-5995
DOI - 10.2136/sssaj1996.03615995006000050007x
Subject(s) - water retention curve , hydraulic conductivity , water retention , porous medium , soil water , saturation (graph theory) , sphericity , water content , materials science , porosity , environmental science , soil science , mineralogy , geotechnical engineering , chemistry , composite material , geology , mathematics , combinatorics
The use of well‐characterized porous media can simplify and improve the efficiency of laboratory subsurface flow and transport experiments. The objective of this study was to present a comprehensive set of hydrologically relevant properties for a unique set of commercially available silica sands. Features of sands selected for characterization included high sphericity, high batch‐to‐batch consistency, Miller‐similarity, and availability in large quantities. Samples of four different sand grades (12/20, 20/30, 30/40, and 40/50 sieve sizes) were characterized for physical properties, chemical composition, water retention, three‐phase air‐non‐aqueous‐phase liquid (NAPL)‐water saturation‐pressure relationships for water and a model NAPL, Soltrol 220, and saturated and unsaturated hydraulic conductivity. Properties common to all sand grades included high chemical purity and low organic matter content. Water retention curves featured well‐defined air entry pressures and the Miller‐similarity of the media was demonstrated for both static and dynamic properties. During water retention measurements, we determined that the common assumption of a uniform vertical water content distribution in retention cells can result in significant errors in uniform porous media. A numerical correction procedure was developed and successfully applied to correct fitted water retention curve parameters, illustrating that potential errors of up to 70% in volumetric water content are made without proper analysis. The characterization data for the four sand grades presented here should facilitate their use in a wide range of laboratory flow and transport studies.