Current region > United Kingdom
Client : National Roads Authority
Value : £322m (€360m)
This PPP scheme consisted of the design, build, finance, operation and maintenance of approximately 10 km of tolled dual carriageway and a 2.3 km single lane carriageway. Incorporating 675 meters of an immersed tube tunnel under the River Shannon with 4 major grade-separated interchanges the project also included 43 other major structures and a 750m causeway across Bunlicky Lake.
Starting in 2006, the preparatory tunnel fit-out included the installation of massive Ballast Tanks, Gina Gaskets, Watertight Bulkheads, Sandflow Pipes, Fenders, and Access Towers in readiness for the Tunnel Float-Out and Immersion.
After two years of dedicated design and construction work, the project achieved a major construction milestone with the completion of the final Immersed Tube Tunnel Elements in October 2008.
Following float out and immersion in the River Shannon, the next phases include:
- Fit out the five Tunnel Elements – each element weighs over 20,000 tonnes and is 100 m long, 25 m wide and 8.5 m high.
- Dredge a 12m deep channel across the Shannon - approx. 400,000 m3.
- Build the 6 South Cut & Cover Tunnel Elements - approx. 20,000 tonne.
- Float out and immerse the Face Tunnel Elements in the channel.
- Cast the three North Cut & Cover Tunnel Elements
John Sisk & Son were part of the DirectRoute consortium who delivered the overall project. Sisk also provided a considerable amount of resources to the Construction Joint Venture in respect of the core management team utilising the particular skills staff have in marine engineering projects of this type
This challenging and complex project opened ahead of schedule in July 2010.
Irish Concrete Society Awards 2010 Infrastructural Category
Structure B11, Cratloe, Limerick. The proportions and scale of this major viaduct are expressed in simple aesthetics. The concrete design and construction are of the highest quality and settle perfectly within a rural environment servicing a very busy traffic flow. Structure B11 of the Limerick PPP Scheme, is in County Clare, near the western end of the Limerick Tunnel.