Historically, simple rocks or crude blocks of concrete were used on the edge of the coasts, mainly in order to hold back the wave forces and dissipate their energy. But these blocks tended to be taken away or to break by the oceans power because their form was not adapted.
It is in 1950 that the first type of armour unit appeard, called Tretrapod. Designed and worked out by the Laboratoire Dauphinois d'Hydraulique (now Sogreah), based in Grenoble in France, this block was largely used everywhere in the world. Tetrapod had been the precursor of many other products such as Xbloc®, ACCROPODE, A-Jacks®, Xbase®, ECOPODE or CORE-LOC. All these armour units intervene in the protection of coastal infrastuctures.
- The protection of the sea fronts prone to strong waves
- To reduce the maximum wave energy