2019 Volume 7 Issue 2 Pages 627-635
It is known that unsaturated soil shows more brittle modes of failure with clearer shear band than fully saturated soil. Investigation of three-phase microstructural changes in shear band of unsaturated soil is important to clarify its mechanism. In the present study, x-ray micro computed tomography (CT) focusing on shear band was performed at different stages of deformation during a triaxial compression test for an unsaturated sand. Variations in the local void ratios, degrees of saturation, the number of grain contacts and the number of water menisci with development of shear band were revealed using image analysis techniques. The relationship between their microscopic behaviors and the macroscopic deviator stress of the unsaturated sand under triaxial compression is discussed.
