Geo-Congress 2020
Effect of Initial Moisture Content on Critical Temperature of Three Sandy Soils
Publication: Geo-Congress 2020: Geo-Systems, Sustainability, Geoenvironmental Engineering, and Unsaturated Soil Mechanics (GSP 319)
ABSTRACT
Once soil temperature reaches a critical temperature due to heat generated from a heat source (e.g., ground-based heat exchangers, buried electrical cables), moisture migration is initiated, which may result in a significant change in soil thermal conductivity. In this study, laboratory testing was performed to evaluate how initial moisture content affects soil critical temperature. Temperature and moisture contents of three sandy soils at 1% and 3% initial moisture contents were measured using a radial-based apparatus, including a centrally placed heating element. While discontinuities near the boundary between dry and wet zones were clearly observed in soils at 3% initial moisture content, the 1% initial moisture content cases had gradual temperature profiles instead of pronounced discontinuities. Temperature and moisture profiles were thus used with soil images to determine critical temperature. As initial moisture content increased from 1% to 3%, moisture migration decreased with an increase in critical temperature average from 31.6 °C to 44.7 °C. This experimental data supports the concept that soil critical temperature is not a constant for a soil compacted to the same density and that other mechanistic attributes are causative.
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Information & Authors
Information
Published In
Geo-Congress 2020: Geo-Systems, Sustainability, Geoenvironmental Engineering, and Unsaturated Soil Mechanics (GSP 319)
Pages: 21 - 30
Editors: James P. Hambleton, Ph.D., Northwestern University, Roman Makhnenko, Ph.D., University of Illinois at Urbana-Champaign, and Aaron S. Budge, Ph.D., Minnesota State University, Mankato
ISBN (Online): 978-0-7844-8282-7
Copyright
© 2020 American Society of Civil Engineers.
History
Published online: Feb 21, 2020
ASCE Technical Topics:
- Cables
- Compacted soils
- Engineering fundamentals
- Equipment and machinery
- Geomechanics
- Geotechnical engineering
- Hydrologic engineering
- Hydrologic properties
- Hydrology
- Laboratory tests
- Measurement (by type)
- Sandy soils
- Soil analysis
- Soil mechanics
- Soil properties
- Soil water
- Soils (by type)
- Temperature effects
- Temperature measurement
- Tests (by type)
- Water and water resources
- Water content
Authors
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