New Fleet of Nuclear Stations
In order to provide energy security and prevent power shortages, the United Kingdom is working towards complete decarbonization of the power generation sector by 2050. The government has commissioned a new fleet of nuclear stations and, at the same time, is investing heavily in renewables like wind, solar, wave and tidal energy generations. The first of these projects to move into the construction phase is Hinkley C, the third reactor set at the site in Somerset in the southwest of the United Kingdom. The project involves the construction of two EPR reactors with a combined power output of 3,200 MW. Construction work on the project began in 2018 with a scheduled completion date of 2023 at a target price of over US$25B (£20B).
EFCO UK, working with Kilnbridge Construction and primary contractor Balfour Beatty, has been providing formwork solutions within the Marine package of the project. At Avonmouth, docks the construction of the inlet and outfall heads has been progressing since early 2019. These precast structures will eventually be rolled onto barges and taken to a location off the coast of the main site and lifted onto the seabed to regulate the flow of cooling sea water to the reactors. In total, there are four inlet heads and two outfall heads that will connect to the end of the 23’ (7 m) diameter tunnels currently being constructed under the sea. With each head weighing up to 6,065 tons (5,500 tonnes) and a projected 80-year lifespan on the seabed, the process for construction and tolerances are at a level rarely seen in the construction industry.
Designed to Avoid Through Ties
In total, EFCO UK has provided over 23,680 ft2 (2,200 m²) [330 ton (300 tonnes)] of PLATE GIRDER®, REDI-RADIUS® and SUPER STUD® forms for the project as well as custom transition cones for the central shafts. One significant challenging specification was for all formwork to contain the loads implied from the cast concrete without internal ties that would prove to be weak spots in the structure given the final environment and duration the structures will be in operation. EFCO provided a solution that combined ring compression and internal bracing to restrain the shaft and void formers and externally anchors, SUPER STUD® A frames and bracing. This approach eliminated the need for through ties in the structure. ◊
The entire project team sees that health and safety culture and performance is a key contributor towards achieving engineering excellence and the world class quality standards required on these class 1 nuclear structures. The active involvement and buy-in of our supply chain members is an essential enabler to realizing this goal. The EFCO Management Team and field engineering support on this project has ensured that this high bar is a realistic target which can be met in a safe and efficient manner.
-Rick Kopec, Contracts Manger