NOVEL CYCLIC TRIAXIAL TESTING ON LIQUEFACTION POTENTIAL OF SANDS

Abstract

The propagation of seismic waves in subsurface soil layers induces complex stress fields. In this study, a novel experimental-based study is carried out on investigating liquefaction potential of saturated clean sands based on cyclic triaxial testing. A discussion of complex loading on nonlinear soil behaviour using both strain-controlled and stress-controlled method is presented. To further compare soil liquefaction response between cyclic stress-based and cyclic strain-based approaches, comparisons of shear modulus degradation between the two approaches of testing due to differing stress, strain and pore pressure responses were depicted and demonstrated. Also, with contractile nature of sandy soils and inability to dissipate excess pore pressure efficiently during earthquake loading, a novel insight of coupled pore pressure generation and dissipation in liquefiable clean sand is discussed with the use of a modified cyclic triaxial testing setup. Finally, a validation study is carried out by constitutive modelling using the bounding surface hypo-plastic model.