Abstract: Some earth and rockfill dams have significant later stage deformations after constructions, which are closely related to the rheology of coarse-grained soils. The study of rheology for coarse-grained soils mainly focuses on mechanical tests and constitutive models. However, particle movement of coarse-grained soils in rheological test is not well evaluated. The CT triaxial rheological test of a single grading aluminite is conducted to investigate the particle movement of coarse-grained soils. The test results show that the rheological process is an adjustment process of particle position from unstable structure state to stable structure state for particles in coarse-grained soils. The rheological process will not stop until all particles reach the minimum energy state. No particles move, rotate, and break under the rheological steady state. The investigation of particle movement for coarse-grained soils contributes to the understanding of rheological behavior of coarse-grained soils, and also helps to provide reference to engineering application.

Key words: coarse-grained soil, CT test, triaxial test, rheology, particle movement, deformation mechanism, stress-strain relationship, mesoscopic fabric