A laboratory investigation was carried out into stiffness and damping of sands as sheared in a torsional shear apparatus. In the drained monotonic and cyclic loading tests, a particular care was taken of the small strain measurements in which the secant stiffness was measured over a wide range of shear strain from about 10-6 to 10-2. Despite the marked differences in the grain size and the sample preparation method among the sands, a fairly good coincidence of the secant stiffness was seen, in common, in the range of shear strain less than about 1 x 10-5 between two types of tests using the monotonic and cyclic loadings. However, the response was softer in the monotonic loading tests for the larger strains. It has also been pointed out that the damping when examined in relation to the normalized secant shear modulus was scarcely affected by the confining pressure, and that the values of damping were smaller than those so far available in the literature
