Cone Penetration Testing (CPTs) Over Water In Belfast

Late summer saw In Situ Site Investigation complete an over water project in the city of Belfast, Northern Ireland. The purpose of these marine works was to carry out an investigation for the modifications for one of the ferry port quays. As this was still a working port, ferries were regularly arriving and departing the area which therefore, had to be kept clear during these times. We had approximately 2-3 hour windows for which to carry out the works. CPTs were ideal for this challenge because they are fast, results are instantaneous, and we could move the rig easily on the barge when needed to allow the ferries to pass safely.

Our mini rig, CPT 003 was craned onto a barge and then chained onto the deck before the barge moved to the different testing locations within the harbour. CPTs were carried out through the moon pool where casing was first lowered through the water column to provide lateral support for the rods and enable testing to commence from the seabed.

A total of 12 test locations were carried out over 5 days and tests reached target depths of 10-15m below the existing seabed. The results were able to ascertain the thickness of the soft sediment (marine deposits onto sleech).