Post-tensioning, Innovation and Sustainability at Bonham Quay Phase 2, Galway

Interspan is proud to have been part of this landmark project in Galway: the construction of post-tensioned slabs for The Calatrava Building, a critical element of Bonham Quay Phase 2. This development is reshaping Galway’s historic Docklands, transforming an industrial area into a vibrant business hub with four new office blocks totalling 34,405 m² of Grade A office space as well as retail, restaurant and cultural space. The office development is designed as four office blocks alongside two public squares that all connect via landscape bridges. Designed to accommodate a working community of 2,600, it includes additional amenities in the development, such as a cultural arts facility and a commuter and fitness centre.

Project Details and Scope

Working alongside the main contractor, John Sisk & Son, Interspan was tasked with the design and construction of post-tensioned slabs for this major commercial project. Our team collaborated closely with Barrett Mahony Consulting Engineers and the consulting engineer designers to ensure that every aspect of the slab design aligned with the project’s ambitious vision.

Construction began on January 10, 2023, and reached its successful conclusion by July 20, 2023, on schedule. This efficiency was achieved, in part, through the innovative use of post-tensioning technology, which allowed for faster construction while maintaining the project’s structural integrity and sustainability requirements.

Post-Tensioning to meet structural and environmental goals

Post-tensioning was particularly suited to the demands of this project, which required slabs spanning grids of 9m x 9m and, in some sections, up to 9m x 12m. The result was slender 275 mm and 350 mm thick slabs designed for optimal load-bearing capacity while minimizing material use.

Using post-tensioned slabs offered several key advantages:

1. Material Efficiency: Post-tensioning significantly reduces the volume of concrete and steel required compared to traditional reinforced concrete. This aligns with Bonham Quay’s goal of creating a zero-carbon campus and achieving the One Planet Living Leadership Standard.
2. Faster Construction: The leaner construction process enabled by post-tensioning resulted in shorter construction times and earlier striking times, which helped the project stay on track.
3. Sustainability: This approach aligns with the project’s broader sustainability goals, minimizing waste and reducing carbon emissions during construction.

Achieving Excellence: Operational Success

Interspan’s involvement in Bonham Quay Phase 2 marked our first project in Galway, and we are proud of the quality and precision we brought to the job. Our team leveraged advanced software, including Ram Concept analysis and design tools, to ensure the slabs met all structural and performance requirements.

The benefits of post-tensioning were clearly demonstrated throughout the project. It enabled a seamless construction process with reduced labour, materials, and time.

Interspan’s work was recognized with a nomination for Sisk Supply Chain Project of the Year, reflecting our high standards across all our projects.

One Planet Living Leadership Standard for Sustainable Construction

What sets Bonham Quay Phase 2 apart is its strong emphasis on sustainability.

This project is the first in Ireland to achieve the prestigious One Planet Living Leadership Standard. Every aspect of the development – from energy use to material sourcing and waste management- reflects a deep commitment to creating a sustainable future.

Interspan is honoured to have contributed to this pioneering project, which exemplifies the potential for post-tensioning and innovative construction methods to support both efficiency and environmental responsibility.

Urban Renewal and Sustainability

Bonham Quay Phase 2 is more than just a commercial development – it represents a forward-thinking approach to urban renewal, sustainability, and modern construction. Interspan’s role in delivering post-tensioned slabs for this project highlights our ability to combine technical expertise with a commitment to sustainable building practices. As Galway continues to grow, Bonham Quay stands as a symbol of the city’s future – where innovation and sustainability go hand in hand.

Top Image: Evercam -Bonham Quay – Dock Road Aerial CGI