Accurate Determination of Moisture Content of Organic Soils Using the Oven Drying Method

Abstract

The accuracy of moisture content values determined for organic soil using the oven drying method is dependent on the oven drying temperature. Some charring of the organic fraction occurs at the standard oven drying temperature of 110 ± 5°C; pore water remains in the soil when temperatures below 100°C are used. A new technique to determine the specific oven drying temperature that yields the correct value of the moisture content for organic soils is presented. Routine moisture content tests should be conducted at the standard oven drying temperature; moisture content values determined on the basis of the recommended oven drying temperature of 60°C include a larger error. A moisture content parameter is introduced to facilitate direct comparison of moisture content values calculated on the basis of different oven drying temperatures.

Keywords:

• Oven drying
• Moisture content determination
• Organic soil
• Particle charring

Acknowledgments

The research was conducted by the author for the M.Eng.Sc. degree at the Department of Civil Engineering, University College Dublin. The support of Dr. Tom Widdis is gratefully acknowledged.