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MOSE project Italy , Immersion of the Chioggia Flood Barrier Caissons

09 July 2013

The Mose Project is a system of mobile barriers which will protect Venice and the lagoon from ever more frequent and intensive flooding. The Chioggia inlet is one of the three gaps between the sea and the lagoon where this barriers will be installed. The barrier of the Chioggia inlet consists of eight caissons, among which are two shoulder caissons and six gate caissons.

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After placing, the shoulder caissons (24x61x24,5 m) will remain partly above water, the gate caissons are installed completely underwater.

Strukton Immersion Projects will carry out the floatation, transport and immersion works for this project.

Due to the nature of the activities and the many interfaces within the floatation, transport and placing process, the dynamic behaviour of the immersion system and the loads on al the systems are being tested in a basins by using a scale (1:35) model.

The caissons (60x45x11,5m) are build in a dry dock close to the trench. A sheet pile wall will form the trench in which the caissons shall be installed.  After the fabrication of the caissons is complete, the dry dock is flooded and the embankment is dredged open. One by one, the caissons are floated and towed into position above the trench. Using a purpose build immersion pontoon here they will be placed on its final position. With only a tolerance of +/- 10 mm they will be installed on temporary jack and with grouting a final foundation will be created.

After placing the caissons and M&E works are carried out. Finally, the steel gate panels are installed in the hinges.