Comparison of cyclic undrained strength of large scale specimens of sand with different specific areas and testing methods

The effects of shearing methods and specific areas on the cyclic undrained stress-strain behavior of sand were investigated by means of triaxial, torsional shear and direct shear tests using large scale specimens. It was found from test results that the liquefaction strength curves for specimens with different diameter almost coincide after making correction for the effect due to membrane penetration. But the liquefaction strength curves in direct shear tests decreases to some extent with the increase in stress ratio due to rocking of the cap. This phenomena become predominant in the direct shear test until the shear strain becomes around 3% in double amplitude. (author)