Micromechanics of creep of granular materials

It is well known that granular materials creep under constant effective stress (Leung et al., 1996; Lade & Liu, 1998), such that creep strain is proportional to log time:

where t₀ is the time from which creep strains are measured. Murayama et al. (1984) proposed a rheological model for creep of sand, and Kuhn & Mitchell (1993) used rate process theory to show that viscous and frictional interparticle sliding could give rise to the sort of creep behaviour observed in soils. However, there is evidence (...