Intergranular void ratio - Steady state strength relations for silty sands

Monotonic undrained shear strength (S_us) data for triaxial compression for three silty sands prepared by mixing non-plastic fines with a particular host sand are presented. Results indicate that intergranular void ratio, e_s, plays an important role on S_us. At the same e_s, (less than the maximum void ratio of the host sand e_max.HS), the silty sand and the host sand show similar S_us. The strength is independent of initial confining stress. When e_s of the silty sand is in the vicinity of, or larger than the e_max.Hs the S_us of the silty sand is very low and it is dependent on the initial effective confining stress. This effect must be taken into consideration in analyzing seismic stability of sites consisting of silty sands.