This category of eight papers describes the consolidation process with time, with very useful information on field data, laboratory testing, analytical formulations and numerical modelling, including reference to the comparison of observed data with predictions. The overall findings are as follows: 1. A relative high vacuum pressure of up to -70 kPa can significantly decrease the required fill height and achieve a desirable degree of consolidation exceeding 95%. 2. 2D finite element analysis for vacuum consolidation showed: (a) a higher rate of effective stress increase as the applied vacuum pressure was increased, hence the increase in shear strength, and (b) the vacuum pressure application has the favourable effect of inducing inward lateral displacement. 3. Vacuum consolidation performance depends on the actual distribution of vacuum along the drain length and permeability and the thickness of the sand blanket. 4. During PVD installation, the intrusion of the upper layer into the underlying layer creates an additional zone where the remoulded permeability of this zone can retard the consolidation process 5. Economic soil improvement techniques such as PVD can be combined with rigid inclusions to accelerate consolidation process and to enhance the shear strength. 6. Coefficient of consolidation determined from oedometer tests and CPTu profiling provide an accurate description of soil consolidation behaviour and estimations for settlement development. 7. The simulation of three dimensional unit cell with a PVD resulted in a faster consolidation rate and a lower predicted excess pore pressure. 8. Vertical drain length can be reduced by up to 20% of the total thickness of clay without significantly affecting the settlement time for surcharge loading alone.
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