Liquefaction-induced volumetric change during re-consolidation of sandy soil subjected to undrained cyclic loading histories

The correlation between the re-consolidation volumetric change following liquefaction and undrained cyclic loading histories of sandy soil was studied by laboratory tests. The strain-controlled cyclic triaxial tests were carried out, and two types of axial strain histories were applied to undrained sand specimens prior to re-consolidation. Based on the test results, it was found that the accumulated shear strain developed in the undrained cyclic shear process is more versatile than maximum shear strain amplitude. In addition, based on the lnv-lnp' relationship for isotropic consolidation behavior and using the p'(i) concept, the relationship between the volumetric strain and the effective mean stress during re-consolidation was proposed. Finally, the hybrid on-line tests by using torsional hollow cylindrical apparatus were conducted to confirm the applicability of the correlation and the proposed model performance under irregular loading conditions. Fundamental re-consolidation characteristics observed under irregular loadings were almost consistent with that obtained by the strain-controlled triaxil tests.