Construction work for the 2nd phase of Port 2000 is in great progress on both sides of the terminals in operation. They involve the completion of six new quay berths that is 2,100 meters of additional quayside, completing the existing 1,400 meters: 1,750 meters (berths 6 to 10) are situated in the western part of the Terminal Porte Océane (TPO) and 350 m (berth 5) east of the Terminal de France (TDF). The delivery of the future berths to the operators is scheduled between mid-2009 and mid-2010.
Made by the Soletanche Bachy France – Atlantique Dragage-Koskalis consortium, the work is broken down into three public contracts:
- the first one for the berths 6, 7 and 8 started in July 2007,
- the second one for the berth 5 started in October 2007,
- and the third one for the berths 9 and 10 started in January 2008.
The three public contracts account for a total amount of 216 million €uro.
The three work sites of this 2nd phase of Port 2000 are carried out at the same time and continuously, around the clock for the construction of the diaphragm walls, five days a week. Perfect co-ordination of the different actors is thus necessary all the more as the volumes involved are very impressive: 200,000 cu. m. of concrete will be produced on site for the construction of the diaphragm wall and the berthing front and up to 450 people work at the same time on the various work sites.
1) First stage, the construction of a watertight enclosure surrounding the future quay to protect the work site. This means the completion of a wall with a grout in front of and behind the future quay wall and the implementation of a dewatering system of the grounds.
2) Second stage, the construction of the quay in the embankment filled in during the first phase of Port 2000 with the same construction technique called diaphragm wall. The ground is vertically dug by a cable special bucket and then a hydro-drill, that is a trench 40 meters deep, one-meter 50 thick and six meters broad. Drilling is carried out under bentonite (mixture of clay and water). At the end of each panel, seals are positioned ; they will provide the link and water tightness between the successive panels thus forming the diaphragm wall.
The framework cages measuring 40 meters high, six meters wide for a thickness of 1.50 meters are dimensioned to make it possible to secure a guaranteed dredging mark of – 17 meters at the foot of the quay. They are constructed on site from steel bars (whose diameter can reach 50mm) carried to Le Havre by rail. They weigh 50 tons each. Once positioned vertically by means of two big cranes, the framework cage is inserted in the trench drilled to that end. The panel is concreted by means of two tubes plunged into the bottom of the trench, thus replacing the bentonite, which is processed to be re-used. With an average of 5 to 6 panels by hydro-drill equipment made per week, the work site of the diaphragm wall moves forward today by about forty meters every week (with a maximum of eighty meters in the busiest work phase).
When the diaphragm wall is well underway (as it is the case at present as regards the berth 5 and the berths 6 and 7) the work site for the capping beam in two parts can start. The berthing front is made in reinforced concrete by sections 12 meters long ; it is supported by a base previously anchored into the diaphragm wall. This beam measures almost 10 meters overall ; that is the same height as that of the tidal range in Le Havre. Then the mooring fenders against which the vessels will berth in the operating phase can be placed.
3) Third stage, pumping wells are constructed over the whole zone to dewater the ground of the wall before intervention of the dumpers which are going to remove some 2.5 million cu. meters of ground on a height of 17 meters in the rear of the 6 future berths. Once this is over, the cramping tie-rods (big steel bars about fifty meters long) will be placed between the quay wall (fixing at two levels) and a sheet-pile wall locat