Publication Details

Heitor, A., Indraratna, B. & Rujikiatkamjorn, C. (2015). Effect of suction history on the small strain response of a dynamically compacted soil. 12th Australia New Zealand Conference on Geomechanics (ANZ 2015): "The Changing Face of the Earth - Geomechanics & Human Influence" (pp. 1-8). New Zealand: The Conference Company Ltd.


The small strain behaviour is a key indicator for assessing the performance of compacted fills. Compaction conditions i.e. initial moisture content and applied energy, govern compaction effectiveness and, thus, the structure and matric suction of compacted soil. During their service life, most earth structures experience changes in hydraulic behaviour owing to climatic changes. While the results of previous research studies indicate that the effect of changes in suction on the dynamic response is significant, only limited research has been engaged in the assessment of the effect of post-compacted changes in suction induced by periods of intensive precipitation (i.e. wetting) and drought (i.e. drying). The seasonal fluctuations of moisture reflected in the soil's suction history have an important impact on the geomechanical performance of compacted soil. In this paper, the aspects related to the effect of suction history of a compacted silty sand soil subjected to cycles of wetting and drying are described. The results not only confirm the importance of the recent suction ratio (or CSR) in governing the mechanical response at small strain but also suggest that subsequent wetting-drying cycles further induce hysteretic changes, particularly when following the wetting paths.