EFFECT OF PRINCIPAL STRESS DIRECTION ON UNDRAINED CYCLIC SHEAR BEHAVIOR OF DENSE SAND

Abstract

A family of undrained static and cyclic torsional shear tests were carried out to investigate the effect of the inclination of the principal stress direction to the vertical axis on the wave-induced strength and deformation of dense sand. The results of the experiment indicate: (1) undrained cyclic shear characteristics remarkably depend on the principal stress direction during initial loading, (2) in undrained cyclic shear, the strength and deformation characteristics are influenced by the principal stress reversal and (3) to evaluate undrained cyclic shear strength for dense sand, we should pay attention to the phase transformation point.