A great deal of triaxial tests were conducted under various influence factors on the Silica sand No.5 with the purpose of investigating the characteristics of particle breakage. Particle breakage was measured by sieve analysis conducted at the different axial strain level after the tests to obtain relevant grain size distribution curves which were quantified by relative breakage. It was found that the particle breakage in relative breakage increases with increasing axial strain and confining pressure. Particle breakage was also caused during consolidation. Denser sample was revealed to cause more particle breakage. Initial stress anisotropy was found to result in more particle breakage during anisotropic consolidation than that during isotropic consolidation but during shearing the higher confining pressure resulted in more particle breakage than the initial stress anisotropy with a relatively lower confining pressure. Particle breakage was found to increase in up convexity with increasing cycle number of cyclic loading but in up concavity with increasing additional axial strain. A hyperbolic model was proposed to correlate the particle breakage in relative breakage with the plastic work per unit volume for the monotonic and cyclic triaxial tests. (C) 2017 Elsevier B.V. All rights reserved.