Abstract
A series of cyclic undrained triaxial shear tests were performed in this study on unsaturated sand materials with different fines content. According to the cyclic loading triaxial tests, cyclic undrained shear strength considerably increased as the degree of saturation decreased. On the other hand, the cyclic undrained shear strength of unsaturated sand reduced as the fine content increased from 0% to 20%. It was clarified in this research that, when non-plastic fines were mixed in sand, cyclic undrained shear characteristics largely changed independent of the degree of saturation. Hence, it is important to evaluate the influence of fines fraction on the undrained strength properties appropriately.
