The initial state of a sand, defined by the void ratio and effective m
ean normal stress, can be used to predict its large-strain response. L
aboratory studies have shown that the shear-wave velocity of a sand is
controlled primarily by the effective confining stresses and void rat
io. Since shear-wave velocity can be measured both in the field and in
the laboratory, there is an increasing interest in using shear-wave v
elocity to define the state of a sand. This paper presents an experime
ntal study of shear-wave velocity interpretation for clean Ottawa sand
based on steady/critical state concepts. The results show that the la
rge-strain behavior of Ottawa sand can be estimated using shear-wave v
elocity measurements combined with a knowledge of the in-situ effectiv
e stress. Knowledge of the state of a sand makes it possible to estima
te the boundary between either a contractant or dilatant sand at large
strains. Based on these findings, a preliminary method to evaluate th
e potential for flow liquefaction using shear-wave velocity measuremen
ts is presented.