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The Normandy Bridge has been inaugurated on January 20 1995. Built on the river Seine, near Le Havre (France), the construction period has spread from 1988 to 1994. At the inauguration date, it was the world record of the cable-stayed bridges with a 856-m span and a total length of 2141-m. The two towers are the world highest bridge towers made of prestressed concrete and weigh 20,000-tons each. The deck is at 52-m over the highest water.
The wire cables that support the span are critical structural elements, and protecting them against corrosion is especially important. Each cable (the bridge has 184 in all) consists of a bundle of wires with seven 15-mm strands each. These strands are hot-galvanized before being formed into wires, and the wires are then clad in a high-density polyethylene sheath before they leave the factory. A petroleum-based wax is used to fill the spaces between the strands, as well as between the wires and the sheath. The same protection is provided for the secondary cables that connect the primary cables to each other.
Many other parts of the Normandy Bridge have been protected by hot galvanization, sometimes supplemented with a coat of paint. The following requirements were specified:
For parts to be galvanized but not painted: 80 micron coating
For parts to be both galvanized and painted: same specification as above, plus a 200 micron coating of powder paint
Thus not all of the galvanized steel used in the Normandy Bridge is visible. Some of it is covered with other materials, such as the polyethylene sheaths on the cables, or paint. Other galvanized components are hidden beneath the roadway they support. In all cases, however, the galvanized coating performs a direct, essential, protective role, by providing a physical barrier that prevents any oxidation of the steel, because of the electrochemical properties of the zinc.
Galvanized steel is used in a tremendous variety of structures on the bridge: guardrails, walkways, ladders, platforms, road supports, cable paths, storm water drains, pylon access doors, crash barriers, light standards, and tubes to protect the bridge cables from vandalism, all have been galvanized and painted.
Other landmarks: Christ the Redeemer, Colossus, Delhi pillar, Eiffel tower, Golden Gate bridge, Great Buddha, Guggenheim Museum (Bilbao), Guggenheim Museum (NYC), Normandy bridge, Oresund crossing, Quebec Bridge, Statue of Liberty, Thames Barrier, Titanic, Tower of the Orologio, Washington Monument
