Behavior of large post-liquefaction deformation in saturated Nanjing fine sand

Abstract

Laboratory tests on the large post-liquefaction deformation of saturated Nanjing fi ne sand were performed by using a hollow cylinder apparatus. The stress-strain responses and the characteristics of excess pore water pressure after liquefaction were studied. It was found that the relationship between deviatoric stress and axial strain presented a sigmoid curve, and there was a good linearity relationship between normalized pore water pressure and deviatoric stress. On this basis, a constitutive model of stress-strain responses and a dissipation model of excess pore water pressure were established. It was found that the results predicted by the two models were in good agreement with the experimental data. The infl uence of relative densities and confi ning pressure on the characteristics of liquefi ed soil were studied. The results showed the relative densities and initial effective confi ning pressure all had an important infl uence on the stress-strain responses of liquefi ed saturated Nanjing fi ne sand. However, the dissipation model of excess pore water pressure after liquefaction was only affected by the confi ning pressure.