Thermomechanical analysis of air-dried whole soil samples

Although the nonreversing nature of the step transition is atypical for glass transitions, the observed matrix softening suggests changes in matrix rigidity near Tg*. This softening is hypothesized to be associated with water bridging individual soil structural units. The slow, nonreversing changes in soil rigidity are expected to affect the sorption behavior of organic contaminants, and the increase in compressibility further suggests relevance for soil mechanical properties.