Stress Fluctuations in Triaxial Testing Of Angular Grains

Stress fluctuations caused by stick-slip instabilities are frequently encountered in laboratory shear testings of granular materials. It is not common to observe stick-slips angular-shaped assemblies, although rounded particles more prone this type behaviour. This paper specifically concerns the deviatoric stress shearing coarse angular glass granules. A systematic experimental program comprising triaxial compression tests was realized investigate effects particle size, confining pressure, and strain rate on mechanism. Particle size effect examined adopting three separate distributions. In order understand influences testing conditions fluctuations, specimens were tested under four different pressures applying two distinct rates. The results showed that both pressure greatly affected whereas influence unclear.