The ship impact protection of the Great Belt suspension bridge

The Great Belt Link suspension bridge is constructed across the most heavily trafficked waterway in Denmark. In this particular area ships with displacements up to 160,000 m 3 may be encountered. To avoid ship impact on the slender side span piers protective works have been constructed around the most exposed ones. The protective works are built up in clay and sand materials and protected against scour by a gravel and stone layer. A theory developed demonstrates that the build up of pore water pressure beneath the bow governs the soil forces acting on the ship. In highly permeable soil such as pebbles or quarry run the pore pressure will not build up and the bow will plough itself into the material. In less permeable materials the bow will ride upon the surface of the slope and the ship will be brought to a stop by friction.