Prediction of Compressibility of Overconsolidated Uncemented Soils

Overconsolidated soils exhibit a bilinear e-log p relationship. During virgin compression, microstructural units form larger stable groups, thereby reducing the operating specific surface and, in turn, net osmotic repulsive forces in the soil. The rebound portion of the e-log p curve is consequently flatter. The generalized relationship for compressibility of uncemented soils in the overconsolidated state has been developed in the form of e/e_L = 1.122 = 0.188 log p_c - 0.0463 log p in which e/e_L is the generalized soil state parameter, p_c is the preconsolidation pressure in kPa, p is the effective overburden pressure in kPa, e is the in situ void ratio, and e_L is the void ratio corresponding to the liquid limit water content (w_LG). This relationship can be usefully employed to predict both the preconsolidation pressure and compressibility responses of overconsolidated uncemented soils.