X-Ray Tomography Investigation of Cyclically Sheared Granular Materials
Yi Xing, Jie Zheng, Jindong Li, Yixin Cao, Wei Pan, Jie Zhang, Yujie Wang
Abstract
We perform combined x-ray tomography and shear force measurements on a cyclically sheared granular system with highly transient behaviors, and obtain the evolution of microscopic structures and macroscopic shear force during the shear cycle. We explain the macroscopic behaviors of the system based on microscopic processes, including particle level structural rearrangement and frictional contact variation. Specifically, we show how contact friction can induce large structural fluctuations and cause significant shear dilatancy effect for granular materials, and we also construct an empirical constitutive relationship for the macroscopic shear force.
Topics & Concepts
DilatantGranular materialShear (geology)Materials scienceMechanicsGeotechnical engineeringComposite materialPhysicsGeologyGranular flow and fluidized bedsLandslides and related hazardsGeotechnical and Geomechanical Engineering