Ship to shore

Coastal safety in the waters around south wales In The Uk Will Be Boosted later this year when the new lifeboat house at Tenby is officially opened. The facility will house one of the Royal National Lifeboat Institution's state of the art – Tamar Class – offshore rescue boats. But the boat house's construction has called for some specialist design and foundations to overcome difficult access to the exposed site.

Marine engineering contractor Seacore installed the 813 mm diameter tubular steel monopiles to support a concrete base slab for the new boathouse and 65 m long sloping reinforced concrete slipway from a jack up barge. Seacore used its own T3 leader mounted reverse circulation drilling rig and hired a BSP 357-9 hydraulic piling hammer to install the piles into rock sockets in the seabed.

“The aim was to establish a rock socket of sufficient depth to gain the required level of sleeve friction and end bearing to cater for the loading of the structure and the forces transmitted by the wind and waves,” said Seacore divisional manager Rob Maynard. “The first piles were intertidal and working from the jack up barge provided a stable platform, whatever the tidal conditions.”

In addition, Seacore constructed a second series of temporary monopiles to support a tower crane to allow main contractor Dean & Dyball to build the boathouse and slipway superstructure.