Brighton Marina was the scene for the biggest continuous concrete pour that has yet taken place in the Brighton and Hove area.
The development under way at the Marina involves new housing, parking and a boatdeck.
The day started at 7.30am and was completed at 6pm, involving 111 deliveries of concrete to the site.
It was confirmed as a record-breaker by cement suppliers RMC.
The concrete was used to form a suspended concrete slab on which there will be a boatdeck and 25 homes.
There will be parking underneath.
The project is the latest of many undertaken by Portslade-based building and civil engineering contractors Adenstar at the Marina, where it has completed over £10 million of work in the last 12 years.
Adenstar's order book has never been stronger with major contracts at Shoreham Power Station and Sovereign Harbour, Eastbourne, and Tunbridge Wells.
Managing director Derek Chapman said: "The company is doing well but I am worried about a general shortage of high-quality supervisors and staff."
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article