Night-time view of Mary Elmes Bridge showing lighting reflected in the River Lee.; Night-time view of Mary Elmes Bridge showing lighting reflected in the River Lee.;

Mary Elmes Bridge, Cork

Connecting Cork – new bridge supports city’s sustainability drive

Designed to enhance connectivity, Cork’s newest pedestrian and cycling bridge combines engineering ingenuity, design problem-solving and excellent project management skills to deliver a beautiful piece of public infrastructure.

Honouring Mary Elmes, known as Ireland’s Oskar Schindler, this transformative bridge link is a key element of Cork’s drive to become a more accessible, sustainable city. But how do you design an elegant yet functional bridge that is easy to construct and install on a busy site?

The overriding challenge for this bridge, the city’s 31st crossing over the River Lee, was to deliver a considered design that was sympathetic to the existing fabric of the city – and easy to install within tight timelines. Arup and architects WilkinsonEyre worked to deliver an understated but visually appealing design; the slender, 66-metre steel shallow arch establishes a connective dialogue with its surrounds. Taking a multidisciplinary approach as lead designers, Arup provided bridge, geotechnical, traffic and electrical engineering along with environmental and cost consultancy services on this critical piece of public infrastructure.

The slender, single-span pedestrian bridge features a central ‘spine beam’ emerging progressively above deck to create distinct pathways for users. The mesh parapets afford uninterrupted views of the river and the cityscape. Quietly complementing its setting, the accessible bridge is aligned with Harleys Street, improving connectivity between the city centre and the Victorian Quarter area. Since opening, the beautiful views have made Mary Elmes bridge an attractive meeting point for locals and visitors alike.

Project Summary

120-year design life

11,000 locals cross daily

66mspan steel bridge

The river crossing strengthens connections between people and the city: a widening at mid-span creates a natural meeting point with timber benches on either side of the central beam. As the mixed-use bridge is not segregated, it encourages users to engage with each other, requiring cyclists to slow down and pedestrians to be more observant.

The Mary Elmes Bridge is a key element of Cork reshaping its vision for the future as a more sustainable, commuter friendly city, integrating with other projects on which Arup is working, such as the Cork City Centre Movement Strategy and Cork Cycle Network.

A trusted advisor to Cork City Council

This crucial new piece of urban infrastructure was funded by Ireland’s National Transport Authority and a grant from the European Regional Development Fund (ERDF), so tight delivery timelines were a major driver: our consultants helped navigate the entire statutory approval process without a glitch.

Arup’s environmental and planning consultants advised on all aspects of the process, including successfully achieving a Section 50 application for constructing over a watercourse. Our water engineers also produced a full 3D flood model, showing that the bridge would not adversely affect the hydraulic capacity of the river.

Working with the City Council and WilkinsonEyre to deliver this new city link, Arup is proud to support Cork in its drive to become a more sustainable, accessible city. ”

Robert Ryan Robert Ryan Associate Director Talk to Robert

Digital collaboration for timely delivery

Close collaboration with architects WilkinsonEyre helped bring to life this unique city link concept. With the architectural vision at the heart of the design process, Arup used modelling techniques to optimise the geometry of the bridge and deliver the most efficient shape to minimise the amount of steel required. The main structure is made of high-grade painted structural steel, with polished stainless steel used for the parapet handrails, enabling a strong visual connection with the River Lee.

Using Arup’s proprietary GSA software, our engineers assessed the dynamic performance of the bridge, including pedestrian footfall and wind vibration to optimise the plate thickness. Using analysis software Sofistik, Arup modelled all stages of construction, ensuring that the bridge’s deflected shape during lifting could be estimated to fit within the allowed 35mm tolerance at each end.

The 3D models of this lightweight structure were parametrically generated using a combination of Dynamo and Revit which allowed for virtual design reviews, ensuring full alignment and coordination throughout the project. As the project supervisor for the design process (PSDP), Arup coordinated the health and safety matters relating to the work of the designers throughout the design stage.

The final model was shared with the fabrication contractor, ensuring that the bridge was constructed to the required geometry and tolerance.

The lighting design showcases the bridge’s slender arch.

Responsive lighting for Cork’s new meeting point

Complemented by lighting, the bridge’s simple structural form has created a functional, beautiful new attraction within the city. The lighting design showcases the bridge’s slender arch with tubular feature lighting below the deck that illuminates the spine beam and decking as well as energy efficient LED fittings embedded into the handrails.

Set on a dimmer panel, the lighting system is controlled by ambient sensors with an astronomical clock, ensuring that the lighting levels on the bridge are responsive to ambient light and seasonal variations in daylight.

Constructability: a key consideration from the outset

Deciding on the construction sequence was an important element of the concept design. Since the bridge had to travel beneath two existing bridges before being lifted into place, the design was developed with constructability and transportation in mind. The bridge was fabricated offsite by Thompsons of Carlow in nine sections before assembling it at Doyle’s Shipping Yard in Cobh, downriver from its eventual home.

The semi-elliptical arched bridge was transported on a custom-made barge, with the ends of the bridge submerged to ensure maximum clearance to both the underside of the existing bridges and the river bed.

In May 2019, the impressive structure was lifted by 500 tonne and 750 tonne cranes, operated by East Cork Crane Hire Ltd. onto the barge. It travelled up the river and was lifted by the same cranes using a tandem lift of 160 tonne and lowered into place across the north channel of the Lee.

Mary Elmes Bridge being transferred up the River Lee on a barge. Mary Elmes Bridge being transferred up the River Lee on a barge.

The bridge was transported by barge under the existing Michael Collins and Brian Boru Bridges, pulled by two tugboats, to coincide with optimum tides for clear passage.