Physical modelling of soft clay using Vacuum-Surcharge Method

In this paper, the large-scale consolidation apparatus was employed to investigate the performance of vacuum preloading with conventional surcharge loading. Several tests were conducted to examine the effect of a vacuum and associated parameters such as smear zone and soil permeability characteristics. The measured settlement and excess pore pressure indicates that the vacuum application has certain benefits to control excess pore pressure for a given total loading application. The analytical modelling for radial consolidation and vacuum preloading considering both variation of soil compressibility and permeability was employed to predict the soil consolidation behaviour. It is shown that the analytical model can reasonably capture the laboratory behaviour.