London’s Elizabeth Line: inside the new Farringdon station

Say hello to the Elizabeth Line, London’s latest tube extension which Andy Byford, Transport for London’s (TfL) commissioner, has said is “truly transformative and fully accessible”, and has “incredibly quick journey times” and “beautiful, spacious, modern surroundings”.

In construction for over a decade, TfL has finally launched the passenger service which travels between 10 new London stations from Paddington to Abbey Wood. The service uses Class 345 trains, that traverse the new tunnels under central London, with 24 trains per hour currently operating.

Farringdon, one of the ten newly built stations, is expected to be the UK’s busiest and became the first Crossrail station to be handed over to TfL back in March 2021. It connects the London Underground with Thameslink to provide links with outer London, the home counties, the City, Canary Wharf, and three of London’s five airports.

E&T took a tour around the development before its grand opening, away from all the crowds, gaining more insight into the construction and design of the station.

Construction work began in 2011 with the Laing O’Rourke Strabag Joint Venture, which carried out piling and foundation works at Farringdon. A joint venture between BAM Nuttall, Ferrovial and Kier Infrastructure (BFK JV) took over the site in 2012.

Duarte Seixas, project manager and representative of the BFK JV, has been on the Farringdon project since the beginning. He described the work done on the station as an “example of perfect architectural and engineering symbiosis”, adding that he was proud of BFK’s ability to turn this vision into a reality and that it will “certainly leave a valuable legacy behind”.

When designing the station, the teams drew inspiration from the goldsmiths, watchmakers, ironmongers, and blacksmiths of Farringdon, Clerkenwell and Smithfields and the Brutalist architecture of the nearby Barbican Centre.

Underground mined platforms connect two new ticket halls. The western end, on the corner of Farringdon Road and Cowcross Street, provides access to and from the Thameslink ticket hall.

In the eastern ticket hall, the design references the Barbican Centre with the heavy metal sliding-screen gates taking inspiration from a barcode for ‘Farringdon’.

As part of the Crossrail Art Programme, passengers can see the work of British artist Simon Periton adorning the walls of the station’s interior. He produced artwork for each of the two ticket hall entrances which draw upon the area’s history of trade and artisanship.

At the station’s western ticket hall, inspiration has been drawn from the nearby diamond and jewellery quarter, Hatton Gardens, with 3m-high back-lit glass panels with digitally printed gems picked out in pinks, greens, and yellows.

Despite having their own unique characters, the two buildings also share a material palette comprising champagne coloured stainless steel cladding and etched glass panels to provide a unified look between the two ticket halls.

As part of this collaborative project, BFK JV inducted 82 apprentices and 10,000 people to work on the construction of the station. “The project team showed continued enthusiasm and commitment to innovation, as well as using new build techniques,” a representative at BAM said.

This major transport interchange site has had to fit within a complex infrastructure network that lies at depths down to 30m below ground. The location and physical constraints created engineering and design challenges that have required a series of customised design solutions.

For example, the station features incline lifts that move on a slope rather than the standard vertical movement. Seixas said that these lifts are the first of their kind on the London Underground system. “[The incline lift] was very challenging to install because it’s not a common thing, but it turned out to be a success,” he told E&T.

Sustainability was also at the forefront of the project. “There was always an effort to see what materials we can use during construction to help reduce our carbon footprint,” Seixas explained. “We [BFK JV] combined our knowledge and expertise to come up with new solutions and looked into what other innovations can be applied to this project to in this area.”

In fact, it was the first and only station to achieve the BREEAM (an industry-standard sustainability assessment method) excellent accreditation in its post-construction review. It achieved this for its dedication to the environment and social sustainability through the design and construction stages, according to BAM.

To create the underground station, the team constructed two vertical shafts at the western ticket hall using secant piles. They later excavated these using top-down methods to gain access to the station tunnel levels. One of these became the logistics shaft for the subsequent tunnelling works.

Four Tunnel Boring Machines (TBMs) used throughout the Elizabeth Line project completed their journey at Farringdon. To allow progress through the shafts, the team filled their lower portion with foamed concrete, which the 1,000 tonnes, 150m-long TBMs tunnelled through.

According to TfL, because of the complex and challenging ground conditions at Farringdon, very extensive grouting was required to compensate for ground settlement caused by the tunnelling. They also constructed five grout shafts to help stabilise the surrounding ground and buildings during the excavation and tunnelling phase.

Two of the TBMs travelled from the western ticket hall to the eastern ticket hall. These formed the 7m pilot tunnel for a subsequent enlargement to 12m diameter to create the platform tunnels using a sprayed concrete lining technique. When the TBMs reached the eastern ticket hall, they both turned offline, and the team buried their tunnelling shields in concrete shrouds.

Once these two TBMs passed through the western ticket hall, construction could start on its concourse and the inclined shaft to allow escalator access to the tunnels. They grafted the concourse onto the side of the Thameslink integrated ticket hall, which was built prior to the 2012 Olympic and Paralympic Games, to allow for future access to the Elizabeth Line as well as Thameslink.

Now the station is complete, passengers can access its 12m diameter platform tunnels from both the ticket halls with a stub central concourse at each end linking the escalators to the platforms. According to TfL, the sweeping lines of the glass fibre reinforced concrete panels, which will become familiar to anyone using the Elizabeth Line, will “provide a clean and elegant setting” for those waiting for trains at this new station.