Cohesive soils have significant cohesive strength and exhibit plasticity. Cohesion between soil particles comes from three major sources, cementation, electrostatic and electromagnetic attraction, and primary valence bonding and adhesion (Mitchell and Soga 2005). The structure of clay in cohesive soil has a great influence in the engineering behavior of soils. The structure of soil refers to the geometric arrangement of soil or mineral particles and depends on genetic, chemical, mineralogical characteristic, as well as past stress conditions of the soil. Interparticle force also influences the soil structure. For...