Direct and indirect observations of local deformation properties of saturated sand specimens in undrained cyclic triaxial tests

Abstract

A procedure to evaluate directly the local deformation properties of sand specimens was developed by using a transparent membrane and adding colored sand particles to the original ones. By combining it with indirect observation based on the image analysis of the membrane deformation, their comparison was made. The local deformation properties of a dense Toyoura sand specimen that was evaluated by the indirect observation during the liquefaction process in cyclic triaxial test up to a double amplitude axial strain of 5% were consistent with those evaluated by the direct observation, except for the regions near the top and bottom ends of the specimen.