Background:
There are several types of mussel farming systems, of which the most common are the longine (extensive), and the raft (intensive). The last has been traditionally used in Spain due to the high concentration of phytoplankton in the water and the availability of eucalyptus wood. As since 2018 Formex® beams are an option, RDC and PREFFOR have adapted in the project OpenMode the concept to be exported to other countries. This required to design modules that can be easily transported in a container, structures that are connectable to create larger floating structures, or even submersible platforms for cold waters, as the North Sea. In total, eight pilots (TRL5 to TRL7) were floated in different sea basins, letting novel farmers to understand this technology and explore its benefits.
Why to use UHPC?
The concept of the floating UHPC farm was launched in 2015 as it increased significantly the durability compared to the wooden farm. In this case, the performance of UHPC allows to introduce new capacities to the structures. The connectable Formex® structures are possible because two beams can be connected with a simple bolted connection in their edges. The submersible structure is feasible because UHPC can stand to be six months submerged in salty cold waters. Finally, texturized UHPC joists can create an element with the same sectional dimensions as the wooden joists, something impossible with ordinary concrete or steel.
Advantages:
- UHPC high bonding capacity allows bolted connections between elements.
- A 12 x 12 m UHPC module can be exported in a container due to the light weight of the beams.
- Formex® farms have proven their suitability to be submerged during winter in lakes where there is ice layer formation.
Achievements:
- Thanks to this project based on the UHPC technology, the raft farming system is used for first time in the Baltic Sea, the North Sea and the Adriatic Sea.
- The average fulfilment of the 19 KPIs was of 136%.
