STRESS-STRAIN CHARACTERISTICS OF SAND IN A PARTICLE-CRUSHING REGION

Abstract

Yield curves of sand in a particle-crushing ragion were determined by a multi-step stress path method under triaxial compression and extension stresses. The yield curves were found to have the characteristic dq/dp=G(η), irrespective of the stress path, where q is the deviator stress, p, the effective mean principal stress and η, the stress ratio. Using the relationship between dq/dp and η, families of yield curves were depicted in both compression and extension stress regions. Based on a new expression for energy dissipation per unit volume, a yield curve equation was derived and this equation was proved to be well comparable with the experimental curve. An equation for predicting the stress-strain relation was also presented. This stress-strain equation was shown to be very conformable with the experimen talstress-strain curves in conditions of constant σ_r and constant p in both triaxial compression and extension stress regions.