Abstract
A series of undrained cyclic triaxial tests were performed in this study on sand-gravel materials with different particle gradation and different relative density. Despite large differences in particle gradation, a good agreement in the liquefaction strength was obtained for specimens having the same relative density. The post-liquefaction undrained strength, also measured after each liquefaction test, was much lager for gravelly soils than that for sands having the same relative density. Empirical correlations were made between the liquefaction strength and the SPT N-value or S-wave velocity, which indicate that, for the same N-value and S-wave velocity, gravelly soils tend to exhibit smaller liquefaction strength than sands.
