Vibro-compaction at a land reclamation site in Phuket, Thailand

Phuket is the biggest island province in Thailand. Located in the southern part of the country, this island is famous and a favourite destination for foreign and Thai tourists alike. Consequently, this province continually develops with booming tourism and hence there is a need for large and advanced infrastructure. Construction projects are increasing each year, but the available land area is limited and land reclamation has therefore become an alternative. Sand backfill material is available on the island. However, the loose sand fill needs to be densified for structural support or structural foundations, and the ground improvement technique called vibroflotation is suitable for improving the sand density in a small area over a short period. This paper presents an assessment of the effectiveness of vibroflotation in the densification of sand fill, which was applied for the first time in Thailand. The standard penetration test values of the sand fill before and after improvement were compared, evaluated and confirmed with regard to liquefaction susceptibility during earthquake occurrences. It was confirmed that the vibroflotation technique can increase the density of sand fill in land reclamation and can increase its bearing capacity as well as prevent liquefaction during earthquakes.