Heidelberg secures Sizewell C concrete supply

Heidelberg Materials UK has secured the contract to supply concrete for the main works at Sizewell C, the new nuclear power station under construction on the East Suffolk coast.

The first deliveries are being used to construct the initial phase of the site’s cut-off wall. This 50-metre-deep watertight barrier, made up of concrete panels and a plastic wall, will allow the excavation of around four million cubic metres of earth to create the foundations for the two reactor units.

Heidelberg will supply approximately 35,000 cubic metres of concrete over the next seven months, initially from its Ipswich plant. A mobile batching plant is also being installed on site and is expected to be operational by the end of the year. The mixes include admixtures supplied by Sika to improve workability, extend placing time, aid compaction and limit groundwater ingress.

Sean Hunter, head of nuclear operations, said: “Our nuclear team has wide-ranging experience in the sector and is sharing best practice and lessons learned from our close involvement in supplying Hinkley Point C over the last decade. Throughout the past 12 months we have supported the Sizewell C team, in collaboration with our supply partners, to develop and trial the concrete mix, supporting the project’s objective to deliver Sizewell under intelligent replication of Hinkley.”

Heidelberg has played a central role at Hinkley Point C, the UK’s first new nuclear power station in a generation. Since 2016 the company has supplied aggregates, cementitious materials, concrete, asphalt and paving services, including the UK’s largest ever structurally reinforced concrete pour of 9,000m³ in one continuous operation. That project required four on-site plants producing 2,200m³ per day, 431,000 tonnes of GGBS, and 6.9m tonnes of aggregate.

The experience gained at Hinkley has shaped Heidelberg’s nuclear quality management system, logistics planning and safety culture – all key elements in securing the Sizewell C contract.