Ali Shafiee - California State Polytechnic University, Pomona
Rouzbeh Dabiri - Tabriz Branch, Islamic Azad University, Tabriz
Faradjollah Askari - International Institute of Earthquake Engineering and Seismology (IIEES), Tehran

A series of undrained resonant column, monotonic and cyclic triaxial tests was performed to investigate the effects of non-plastic fines on the dynamic properties of Firoozkooh sand. Specimens of sand-silt mixtures were prepared at different densities, and tested under various confining pressures. Test results revealed that shear modulus decreases with fines, and increases with relative density and confining pressure. Normalized shear modulus is not affected by fines, relative density and confining pressure, while damping ratio is affected by fines and confining pressure. Finally, field cyclic resistance ratios versus normalized shear wave velocity values are developed on the basis of cyclic triaxial and resonant column tests.

Firoozkooh sand, Non-plastic silt, Shear modulus, Damping Ratio, Cyclic Resistance, Shear wave velocity