Abstract
Torsional shear tests were conducted to study the cyclic behavior of anisotropically consolidated sand, focusing deformation characteristics after phase transformation. Loose to medium-dense sand specimens were subjected to undrained cyclic shearing under constant vertical and horizontal total stresses with various consolidation stress ratios K=σ′h0/σ′v0=0.33 to 1.0. For cases with K≤0.5, stresses reached phase transformation state during the first cycle of shearing, then the secant torsional shear modulus increased asymptotically with the number of cyclic repetition. The normalized shear modulus correlated with damping ratio, which was calculated from energy dissipation in torsional stress-strain loops.
