Thermal volume change of poorly draining soils I: Critical assessment of volume change mechanisms

The thermal volume change of soils is typically interpreted using the stress history and changes in yield stress with temperature (thermal softening). However, the path followed to reach a given stress state may lead to different thermal volume changes. Alternative mechanisms of thermal volume change are explored using data from the literature and isotropic, drained heating tests on compacted silt. No relationship between thermal volume change and degree of saturation was observed. However, a clear relationship with the secondary compression prior to heating was observed, indicating that thermally accelerated creep may provide better thermal volume change predictions than thermal softening.