Narrow bridges

Adjustable steel bridges to transport people over 360 km/h HS2 trains

The contractors created adjustable steel bridges to transport pedestrians, cyclists and horses on the 2 high-speed railway.

The EFKB consortium has released images of planned level crossings for 11 locations in Buckinghamshire, Oxfordshire and Northamptonshire.

EKFB – made up of Eiffage, Kier, Ferrovial Construction and Bam Nuttall – worked with designers Arcadis Setec Cowi and architects Moxon on the bridges.

They were designed to handle the pressure waves created by trains passing underneath at speeds of up to 360 km/h.

EKFB designers have developed bespoke engineering criteria to model the effect on the structure and design uncomfortable vibrations. As an added precaution, the bridges can also be adjusted after construction to ensure the solution works.

The bridges will be made of weather-resistant steel, which ages to a russet brown, in an effort to match the surrounding countryside.

The sides of the lightweight bridges will lean outward to maximize views of the sky, while the plates that form the structure will be angled to appear narrower and lighter.

Each span will be slightly higher in the middle so that they “appear to jump over the railroad”. Although most bridges consist of a single 42m span, the longest bridge will be 102m.

To improve manufacturing and assembly efficiency, all bridges will have the same basic shape, with walkways built into the earthworks on either side to make them stepless.

Designed with advice from the British Horse Society, the bridges carrying bridle paths will follow the same basic scheme, with a non-slip recycled rubber deck and a structure acting as a baffle to prevent horses from being distracted by passing trains . The walkways will be 2.5m wide, while the bridle paths will be 3.5m wide to allow two horses to pass comfortably and safely.

The internal faces of the bridges will feature oak panels and perforated stainless steel to allow views along the railway line.

HS2 Design Director Kay Hughes said: “HS2 will provide fast and frequent carbon-free journeys between London, the Midlands and the North. But it is also essential that we keep the communities on either side of the railway connected.

“That’s why I’m excited to see the first standard walkway designs for the project. The sleek decks have been specially designed for Bucks, Oxon and West Northants, with weatherproof steel beams to match the tone of the surrounding countryside.

“I hope that walkers, cyclists and the community will welcome the new bridges and benefit from the tremendous high quality design work that the design team has undertaken to develop them.”

EKFB Engagement Manager David Griffiths-Allen said: “EKFB is building over 80 bridges across an 80km section of HS2, 11 of which are specific to connect local communities on foot and facilitate accessibility for local populations and the equestrian community.

“We are thrilled with the design concepts for the bridges and have put a lot of thought and thought into making both designs friendly to the landscape and beneficial to the people who will use them.”

Moxon Managing Director Ben Addy said, “Safety is always paramount, but accessibility and transparency have also been key design drivers for these bridges – features you wouldn’t always associate with railway bridges.

“The design team looked at how we could make the approaches to the bridge and the landscape around them completely accessible to create a seamless user experience for everyone, whether you were traveling on foot, by bike, on horseback or with any type of vehicle. mobility aid.

“With a simple yet handcrafted structure, we combined contrasting materials such as oak and steel, giving a warm aesthetic and creating a tactile surface for people on the go.”

The first gateway should be installed in October 2023.

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