Premium
Entrapped Air Content and Hydraulic Conductivity of Quartz Sand During Prolonged Liquid Flow
Author(s) -
Gupta Rajinder P.,
Swartzendruber Dale
Publication year - 1964
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/sssaj1964.03615995002800010016x
Subject(s) - hydraulic conductivity , quartz , conductivity , capillary action , permeameter , geotechnical engineering , mineralogy , environmental science , materials science , soil science , geology , chemistry , composite material , soil water
Boiled deionized water, with and without 0.1% phenol, was passed through permeameters filled with several types of quartz sand. In addition to measurements of hydraulic conductivity, the sand‐water system inside the permeameters was periodically subjected to a static gauge pressure ΔP, and the resulting volume change Δv was recorded by the movement of a mercury droplet in a capillary tube. The quantity Δv/ΔP was found to be a highly sensitive indicator of the air entrapped within the wet sand. For sand wetted at atmospheric pressure, Δv/ΔP was found to be high initially, and then to decline sharply as flow proceeded. When the hydraulic conductivity reached its maximum value, the decrease in Δv/ΔP flattened out abruptly, but a slow decline persisted as flow continued. When the sand was wetted under vacuum, the high initial value and subsequent rapid decline in Δv/ΔP were eliminated. Since Δv/ΔP was always observed to decline with continued flow, even when the hydraulic conductivity was undergoing a drastic decrease, it was concluded that flow‐associated reductions in hydraulic conductivity, observed in the present and in previous similar experiments, were not caused by an accumulation of entrapped air originating from dissolved air released by the flowing liquid.