The construction of a huge deck that will help support the platforms at Birmingham's new HS2 station has begun with the first of more than 556 concrete beams lifted into position.

The huge horizontal beams – up to 34 metres long and weighing as much as 58 tonnes – will support the seven platforms being built at Curzon Street station. Each one of the reinforced concrete beams is being precast off-site before being moved into position in a meticulously planned operation.

In March, HS2 announced that all 2,011 concrete piles that form a key part of the station’s foundations had been completed.

Once complete, the station will stretch for around 450 metres between Moor Street and Millennium Point with onward connections to the city centre, Digbeth and Eastside. A new tram stop will also be built under the station as part of the line currently under construction towards Digbeth and the site of Birmingham City’s new football stadium.

Construction of the terminus is being led by HS2’s construction partner, Mace Dragados, which is working with subcontractors MPB to lift the concrete beams into place. This work is initially focused on the area where the tram will pass under the station, so it can be handed over to Midlands Metro Alliance to begin laying track as early as possible.

For most of their length, Curzon Street’s seven platforms will be built on a viaduct-like structure supported by 188 concrete piers. These will form a huge 13,370 square metre deck – the size of two football pitches - which will support part of the platforms and connect to the viaducts coming into the station from the east.

Martyn Woodhouse, project director at Mace Dragados Joint Venture, said: “Lifting these first beams into place is a major logistical and engineering achievement, and a testament to the coordination across our teams and supply chain. Each installation has been carefully planned to ensure it’s carried out safely and efficiently, particularly in such a constrained and operational environment.

“This work is laying the groundwork for the platforms and brings us another step closer to delivering a world-class station for Birmingham.”

Beneath the station, more than 2,000 piles, ranging from six to 24 metres deep, have been sunk into position by Mace Dragados, working with specialist subcontractor Keltbray. An eight-metre-high retaining wall has also been built at the western end of the site – where the land rises up towards the city centre - and 47,000 cubic metres of material excavated to create a level base for the platforms.

At the peak of the work, more than 1,000 people are expected to be employed on the Curzon Street project, both directly and via Mace Dragados’s UK supply chain.