This paper presents the results of numerical simulations carried out using three dimensional discrete element method (DEM) along with laboratory physical experiments with and without end restraint effect on the shear behavior of glass beads. Drained triaxial tests have been carried out in the laboratory with 9200 uni-sized glass beads with and without end restraint effect. Same number of spherical particles has been generated in the numerical simulation using DEM with Hertzian contact law and equivalent Hertzian with linear contact law. The results obtained from the numerical simulations were compared with the laboratory triaxial experiment with appropriate scaling for the input parameter for numerical simulation. It is observed that end restraint conditions existing in conventional laboratory triaxial test significantly affect the shear behavior of glass beads when compared with test without end restraint condition (with smooth frictionless boundary). A matching between simulation and experimental result without end restraint is obtained for deviator stress versus axial strain curve for a shear modulus and a contact friction of 0.01 GPa and 11° respectively. © 2005 Taylor & Francis Group.