Laboratory Evaluation of Coefficient of Radial Consolidation Based on Pore-Water-Pressure Dissipation and Settlement

摘要

Modified and standard Rowe consolidation cells were employed to investigate the behaviour of soft clays during vacuum assisted radial consolidation. Degree of consolidation (DOC) and the back calculated value of coefficient of radial consolidation (c_h) based on measured settlement and excess pore-water-pressure (u_w) dissipation curves were compared. The DOC and c_h, based on pore water pressures are shown to be less than those based on settlements. The vacuum pressure-total surcharge ratio (VSR) is found to be an important parameter controlling the rate of the consolidation. Moreover, the coefficient of radial consolidation (c_h) based on conventional oedometer testing could not accurately predict the consolidation behaviour of soft soils under varying VSR. Finally, a semi-empirical model incorporating the relationship between VSR and a modified coefficient of radial consolidation is introduced.