Temperature-Controlled Infrared Drying Characteristics of Soils

Abstract

Measurement of the moisture content of inorganic soils is frequently needed for many engineering activities. The standard test method by ASTM D2216 is very accurate, but the associated drying time up to 24 h is not always desirable. This study investigates the usability of infrared (IR) drying of inorganic soils in reducing the drying time under constant temperature. It was found that accuracy of the proposed IR oven method is excellent and the associated drying time is 80% less than that of a conventional convective oven. Drying time for zero plasticity soils such as sands was found to be about 1 min per gram of initial sample mass. Soil plasticity was found to increase the drying time up to 100% compared to that of zero plasticity soils.

Keywords:

• Drying time
• Hygroscopic material
• Infrared drying of soils
• Moisture content

ACKNOWLEDGEMENT

This work has been financially supported by TÜBİTAK of Turkey through project 106M231. Olcay Polat conducted most of the experiments. Erdinç Keskin and Cüneyt Yilmaz also helped with the experiments and with the data reduction. This support is greatly acknowledged.

Notes

NA = Not applicable.

∗ = Approximate values. ^[11]

∗PI is determined on material passing through a no. 40 sieve (0.425 mm) according to ASTM D-2487.