Long-term settlement analysis of partially improved thick clay deposit

Prefabricated vertical drains (PVDs) were partially or fully penetrated into thick clay deposits at a reclamation project in Busan City, Korea. Elasto-viscoplastic finite element analysis is conducted to predict the long-term behaviors using a macro-element technique. Settlements predicted using laboratory-based and back-analyzed soil parameters are in good agreement with monitored data. The relationships of time versus volumetric strain and excess pore pressure at each element are effective in investigating the overall behaviors; that is, the settlements in the improved zone degrade from steep to gentle slopes, whereas those in the unimproved zone change with a relatively gentle slope. The effect of partially penetrated PVD on ue dissipation appears to be in relatively good agreement with results obtained by Ong et al.'s (2012) method.