Practical considerations for using vertical drains in soil improvement projects

摘要

More than 140 million meters of prefabricated vertical drains (PVDs) have been installed for the soil improvement work for the Changi East land reclamation project in Singapore. Some useful design and practical experiences have been gained from the project over the years. The objective of this paper is to highlight some practical considerations in the use of PVDs in soil improvement projects. These include the factors that control the selection of PVDs, quality control tests for PVDs, selection of design parameters and smear effect. The adaptability of some of the design criteria is evaluated based on the Changi experience. A design approach of using a higher surcharge to shorten consolidation time is also elaborated.