Consultant Merin Konsult and Danish contractor Per Aarsleff were this week carrying out a huge 180,000m² extension to Muuga Port, 17km east of the Estonian capital Tallinn.
Four hundred and twenty tubular steel piles up to 1.67m in diameter and 45m long were driven into the seabed and backed by pairs of 22m long steel sheet piles to build a 480m combination retaining wall, linked to a new 800m breakwater built around a 4m high geotextile faced limestone retaining bund.
In addition 1.5M.m³ of sea-dredged fill was used to complete the extension. Tens of thousands of 34m deep vertical drains were also installed in the underlying clay to accelerate settlement, which must be no more than 200mm by the time the project is complete in early 2010.
A second line of smaller diameter piles are also being installed to provide foundations for twin rail tracks to take the existing and new quayside container handling cranes.