Breakwaters for ports & harbours


Xbloc placement Calais, France

The main function of breakwaters is to create a sheltered basin for vessels. The breakwaters are typically built in water between 10m and 25m deep. The breakwaters need a crest which high enough to reduce wave overtopping to acceptable volumes. 

On the exposed side of breakwaters, the armour layer absorbs the energy of the incoming waves. The size of the armour blocks depends on the height of the incoming waves. 

Typically breakwaters are designed with a crown wall on top, but if no activity is planned on or directly behind the breakwater, sometimes the crown wall can be omitted. In these cases the breakwaters are also equipped with armour protection at the crest and rear side. 

The high porosity of the Xbloc and XblocPlus armour results in a reduction of concrete consumption compared to other concrete armouring systems available on the market. This means fewer units, less concrete used and less CO2 emission. This makes Xbloc and XblocPlus the most economic concrete armour solutions in the market.

This concept has proven strong in practice. A good example here is the Port of Calais where an Xbloc-reinforced breakwater protects the harbour. The Xbloc sizes used in the project are 4, 6, 10, 12 and 14 m3. The total concrete amount used is approximately 110.000m3. Thanks to their angular shape, the units interlock very efficiently - this provides high hydraulic stability.