ABSTRACT
Assessing the dynamic response of soil in the laboratory often comprises conducting cyclic shear tests involving triaxial or direct simple shear test apparatus. In some cases, either post-cyclic monotonic shear loading or post-cyclic reconsolidation loading are performed to assess the liquefied-strength or post-seismic settlement characteristics, respectively. However, tests conducted with repeated cyclic loading phases applied on soil specimens reconsolidated after previous loadings is very limited. Repeated cyclic loading can provide insight with respect to the effects of repeated seismic activity including densification and soil fabric changes that occur after cyclic loading phases. With these factors in mind, constant-volume cyclic direct simple shear tests were performed on a reconstituted Fraser River silt specimen that was normally consolidated initially to a vertical effective stress of 100 kPa. Tests with consecutive repeated cyclic loading phases were performed with increasing cyclic stress ratios. The cyclic shear response, including accumulation of shear strain and development of pore water pressure, from eight repeated cyclic shear loadings phases are presented herein.
