JIFMAR was contracted to install the mooring lines of an anti-trespassing floating barrier, to be installed on the entrance of the military harbour of Brest.
The 8 anchoring lines were made of concrete deadweights of 20T & 8T assembled together on 60m long chains, and to be installed within 12m of water depth with a precision of +/-1m.
Initial plan was to use soft sling to install the deadweights without any subsea disconnection. However, soft slings showed to be too fragile and not easily managable on such length (30m). Divers from DCNS were contracted and steel wire were used to complete the work.
The job was performed satisfyingly and can lead to others, as this prototype is likely to be installed on other military harbour of France
LESSONS LEARNT :
Installation shall be performed using steel wire or release hook to be more reliable.
Detailed lessons learnt available in the projects folder.