Large Strain Consolidation with Time and Distance Dependent Boundary Conditions

Clogging is often observed in the improvement of dredged fills using the vacuum pressure combined prefabricated vertical drains. Due to the clogging at the drain, vacuum pressure needs some time to achieve the target value, and the magnitude of the pressure reduces along the drainage path in the spreading process. In this study, a large strain consolidation model is built under boundary conditions varying with time and distance to the vacuum connector. The model is solved by a numerical method to compare the total consolidation and the radial distribution of excess pore water pressure under different boundary conditions. The large strain consolidation model is also compared with results of small strain consolidation and measurements in field tests with the variation of vacuum pressure considered. Based on the comparisons, it is found that time-dependent variation makes impacts on the rate of consolidation, and the distance-dependent variation affects the ultimate consolidation results.