Multiscale modeling of a sensitive marine clay

This paper examines the mechanical behavior of a sensitive marine clay. Various laboratory tests on intact and reconstituted samples of Guinea Gulf marine clay were performed under isotropic compression and drained triaxial compression at constant confining stresses. Microstructure analysis on intact and reconstituted samples was also carried out under different loading conditions. The effect of inter-aggregates bonding on mechanical properties is discussed. Based on experimental analysis, a new modeling method is proposed. In this approach, the clay is regarded as an assembly of aggregates of clay particles. An inter-aggregate contact law is introduced relating contact forces to aggregates relative displacements. The deformation of the assembly can be obtained by integrating the movement of the inter-aggregate contacts in all orientations. Thus, the effect of inter-aggregates bonds and debonding is considered in a direct way. The model is evaluated through comparisons between the predicted and measured results on Guinea Gulf marine clay. The evolutions of local stresses, strains, and bonds in inter-aggregates planes are discussed to explain the anisotropy induced by the applied loading. Copyright (C) 2010 John Wiley & Sons, Ltd.