The Influence of the Compaction Energy on the SWCC of a Residual Soil

The proliferation of the use of the soil water characteristic curve (SWCC) to obtain the unsaturated soil parameters is unavoidable and in some cases desired. However, the complex interrelation between soil water content and soil water suction makes the adequate indirect determination of the unsaturated soil parameters a difficult task. There are many aspect to be considered when using SWCC for predicting mechanical or hydraulic behaviour of the soil. The paper describes a study involving a residual soil of Gneiss, compacted using three different compaction energies. Soil water characteristic curves (SWCC) are obtained with volume measurement during the drying process and the soil suction was obtained using the filter paper method. The filter paper was placed in direct contact with the soil sample. Discussions on the relationship between the compaction energy, SWCC shape and the drying behaviour of the soil samples are given.