LIQUEFACTION PROPERTIES OF TOYOURA SAND IN CYCLIC TORTIONAL SHEAR TESTS UNDER LOW CONFINING STRESS

An elasto-plastic model to describe the undrained cyclic behavior of saturated sand with initial static shear

With the aim of simulating the behavior of saturated sand with initial static shear (i.e., sloped ground) undergoing undrained cyclic loading, which leads to liquefaction and large cyclic shear strain development, an elastoplastic constitutive model which can describe both monotonic and cyclic torsional shear behaviors of saturated sand under drained and/or undrained conditions is presented. It...

FE-Modeling of Shear Resistance Degradation in a Sand Body During Cyclic Shearing Under CNS Condition

The behaviour of dry and cohesionless sand body in a cyclic interface shear box test under a constant normal stiffness (CNS) condition is numerically studied. Do this end finite element calculations are carried out using a micro-polar hypoplastic model, where the mean grain diameter of the sand material is used as a characteristic length of the micro-structure. The constitutive equations for th...

The effect of nano-Kaolinite on liquefaction resistance of liquefiable sand

This study is an attempt to investigate the effect of the nano-kaolinite concentration on the liquefaction resistance of liquefiable sand from Gorgan city of Iran. To examine the influence of the nano-kaolinite concentration on the liquefaction resistance of nano-kaolinite-sand mixtures, three different nano-kaolinite concentrations: 3%, 6% and 9% were prepared. Cyclic triaxial tests were condu...

Investigation of Liquefaction Mechanism in Double Sand Lenses

In many cases of heavy earthquakes, liquefaction has resulted in serious damages. Existing anisotropy in soil layers results  in some difficulties to realize the reason for these phenomena. Loose sand lenses buried in fine soils are one of the cases which may result in these problems and as a weak point during the earthquake can cause this phenomenon. In this paper, using FLAC 2D software, doub...

Effect of Cementation on the Shear Strength of Tehran Gravelly Sand Using Triaxial Tests