ABSTRACT
The shakedown theory is a tool to characterize the state of the structural system of an unbound granular material that is subjected to repeated loading when its response has become resilient in nature and no further accumulation of plastic strain occurs. This paper demonstrates the application of both shakedown and packing theories to characterize permanent deformation behaviour of unbound aggregate materials. Ranges of shakedown phenomenon (Ranges A, B and C) for some selected unbound materials have first been investigated based on their permanent strain responses. The Disruption Potential (DP) of the Primary Structure (PS) of the aggregate assemblage has then been determined for each grain size distribution based on a packing theory model. The DP was found to characterize satisfactorily the three types of shakedown ranges. Further, a finite element analysis was performed to determine the shakedown limit load as a mean stress and a dimensionless shakedown load. The analysis was simulated using the Mohr-coulomb yield criteria for a three-dimensional cylindrical sample. From this study, the DP value was found to compare favorably with the predicted mean stress and dimensionless shakedown load.
