Opportunity
Manchester's main city centre stations were not connected to each other directly by railway lines and the existing railway lines were running at full capacity during peak times. The Ordsall Chord was proposed to connect the stations to help reduce congestion and open up new routes for passengers.
Creating these connections sounds simple on paper – installing 540m of track near Ordsall Lane to the south west of the city. But in reality, building the Ordsall Chord required realigning existing track, building new bridges and viaducts, removing redundant structures and restoring others – all while working near a live railway, roads and a river, heritage structures, local businesses and the public.
Solution
Connecting the two bridges which form the Ordsall Chord is a transition piece linking the 2.2m deep girder of the network arch bridge and 2.8m deep girders of the Trinity Way Bridge. Hexagonal in cross-section and with a complex geometry, this element was analysed and modelled in 3D to aid design, fabrication and erection.
Building information modelling (BIM) was used to understand the interaction of new and old structures on this project, incorporating all major structures and foundations and buried services. This aided coordination of all disciplines on this project from an early stage.
The new viaduct’s landmark structure, the River Irwell Crossing, is the first network arch bridge in the UK and the first asymmetric network arch bridge in the world. All structures were designed completely in 3D. For the River Irwell Footbridge, which runs below the Ordsall Chord’s network arch bridge, the design was delivered as a 3D computer model without conventional design drawings. This saved 15% off the cost, and 20% on the programme.
Outcome
The Ordsall Chord is easing traffic congestion, reducing journey times and enhancing rail capacity across north England. The efficiency of the network arch bridge meets the architect's aspirations for an elegant structure with all necessary performance characteristics for the railway. As part of the works, a new public realm was created to reveal the area’s rich industrial heritage. Elements of this were seen in their full glory for the first time in over 150 years.
Benefits of the Ordsall Chord
- New direct links to Manchester Airport from across the north of England.
- Congestion at Manchester Piccadilly reduced by a quarter with some services being rerouted through Manchester Victoria.
- Greater capacity on the railway for more frequent trains.
- Improved connectivity and residential developments.
The project has already won several awards including the Tekla Global BIM Award for Infrastructure, RICS North West Infrastructure Award, North West Regional Construction Award for Digital Construction, Railway Industry Innovation Awards Major Project of the Year, and British Construction Industry Award for Partnership Initiative.