| Recent advancement in unsaturated soil mechanics revealed the influence of the degree of saturation on dynamic properties of soils due to inter-particle suction forces. However, because of the complexities in states of stress and experimental modeling, most of the recent studies only focused on small-strain shear modulus. Cyclic triaxial system at the University of New Hampshire was renovated and modified for suction control to enable testing the soils with different degrees of saturation at medium to large strain levels. A set of strain- and stress-controlled cyclic triaxial tests were performed on dry, saturated, and partially saturated sand specimens. The measured moduli were consistent with the predicted values from the available empirical relations. Higher modulus was estimated in specimen with mid-range degrees of saturation. Although the results indicated the success of the newly developed suction-controlled system, there were challenges in testing process that needs to be addressed in future work. |
