EFFECT OF HYSTERESIS ON THE SHEAR STRENGTH OF A RESIDUAL SOIL

An air-dried granite residual soil was statically compacted and tested in a modified direct shear apparatus to examine the hysteresis effect of wetting and drying on shear strength. Identical soil specimens were tested at wetting and drying under controlled air and water pressures. Brittle and ductile shear behaviour were exhibited at wetting and drying, respectively. The soil at wetting had a lower shear strength as compared to the soil at drying under the same matric suction. This difference in the shear behaviour is due to the lower water content in the soil at wetting as compared to the soil at drying. (A) For the covering abstract see IRRD 881647.