Project

A major port for the Indian Navy is being built under the codename “Seabird” and located at Karwar on the western coast of India, 100 km south of Goa. The first phase of the project involves the construction of two breakwaters having a base width of 120 m and a total length of about 5 km.

The natural soil, consisting of clay and soft silt, has been removed from the seabed by dredging and the trench refilled with imported sand.

The Soil and Improvement Scheme Soil improvement was carried out in order to achieve the following targets:
• uniform soil condition
• reduction of settlements
• minimising of long-term settlement
and creep
• safety against liquefaction

The Offshore Site works

The method selected was Keller’s deep Vibro Compaction Technology. Four S-300 vibrators, extended to 18 m and held 3m apart by a specially constructed steel frame, were suspended from a crane to compact
the imported sandfill to a depth of 3 to 4 m under a water depth of 10 m.

The Quality Control

• Positioning of the compaction points
by GPS (Global Positioning System),
• During compaction process by Keller
M4 Recorder, monitoring depth, power
consumption and time
• Pre- and post compaction CPT with
seabed-CPT-machine.