ABSTRACT
One-dimensional consolidation and desorption behaviour of highly plastic clays (MX 80 bentonite and Speswhite kaolin) were experimentally determined in this study. Initially saturated clay specimens were subjected to an increase in suction employing axis-translation technique and salt-solution technique to cover a suction range of 10 kPa to 300 MPa. Consolidation tests were carried out with a maximum applied vertical pressure of 3.2 MPa. The water content and the volume of the clay specimens at each applied suctions were measured. The study revealed that a vertical pressure increase was more effective in reducing the water content and the void ratio for the bentonite studied, whereas a suction increase was more effective in removing water from the kaolinite. The possible structure and fabric of the clays at saturation, at commencement of desaturation, and at residual shrinkage stage are discussed. The observed differences in the volume change and water retention behaviour were attributed to the differences in the mineralogical properties of the clays.
