Constitutive for granular soil-structure interface behavior

Abstract

This study was carried out to investigate the behavior of granular soil structure interface under Constant Normal Load (CNL) and Constant Normal Stiffness (CNS) conditions by using Casagrande direct shear apparatus. Dry sand (૪_max = 17.90 kN/m³ and ૪_min = 15.50 kN/m³) was used in this study. Two distinct initial densities (D_r = 35% and D_r = 85%) with three values of initial normal stress (σ_n = 100, 200, 300 kPa) were investigated. It was found that the initial normal stress, initial density and loading conditions (CNL and CNS) mainly influenced the interface behavior. Under CNS condition, the dilation or contraction provided the variation of normal stress depending on the initial density. A small variation of normal stress could be observed. A constitutive modeling of granular soil-structure interface for which the changes in stress state took place depending on the initial boundary condition was proposed. Relevant variables were discussed. The simulations showed a fairly good agreement with the results obtained from interface direct shear tests.