87 %
reduction in carbon dioxide equivalent
Sustainability
Glasgow Airport Investment Area (GAIA) – Ancillary Infrastructure
We provided design services for Wills Bros Civil Engineering on the Glasgow Airport Investment Area (GAIA) project, which was led by Renfrewshire Council and jointly funded by the UK and Scottish governments through the £1.13bn Glasgow City Region Deal.
The project provides improved connections to Glasgow Airport, including the upgrade of the existing road network, two new bridges over the Black and White Cart Rivers, and new and improved connections to existing cycleways and pathways.
In collaboration with Wills Bros, we developed an innovative approach to underground power cable protection. By creating a lightweight embankment using storm storage cells, we facilitated an 87% reduction in carbon compared to the reference design.
Key details
Project name
Glasgow Airport Investment Area (GAIA) – Ancillary Infrastructure
Client
Wills Bros Civil Engineering
Location
Glasgow, Scotland, United Kingdom
Services provided:
- Civil engineering
- Structural engineering
- Bridge engineering
- Geotechnical engineering
- Ground improvement
- Project management
Challenge
The construction of a 1.6km road which crosses a series of 132kV underground power cables was a major challenge. The cables had fragile oil-filled cores and served over 20,000 homes and businesses, including Glasgow International Airport. They were very vulnerable to damage by settlement and movement, vibration, overheating and accidental damage during construction.
The preliminary design to protect these sensitive high voltage cables involved placing a series of steel reinforced concrete beams to span reinforced concrete piles – effectively creating a piled bridge. This structure was designed to prevent settlement of the cables in the soft ground, while also preventing any further embedment of the cable in soil, which could cause overheating and loss of electrical capacity.
However, this initial proposal was carbon intensive, with an impact of over 1,546t of carbon dioxide equivalent (CO2e). This would have accounted for almost 13% of the project’s projected footprint.
It also presented practical difficulties, such as the need to provide a heavy piling platform for piling operations, the risk of vibrations from piling damaging the cables, and the risk of accidental damage to the cables should the tall piling rigs accidentally overturn during construction.
Solution
In partnership with Wills Bros, we developed an innovative approach to protect the underground cables. Through the creation of a lightweight embankment using storm storage cells, we protected the electricity transmission lines in a way that allowed suitable temperate control without compromising safety. These cells are very lightweight, being over 95% air, and yet are still robust enough to sustain traffic loads.
Overall, the team achieved an 87% reduction in carbon for this element of the project when compared with the preliminary design. It delivered an enormous saving in embodied carbon, while also providing for a quicker and safer construction operation, and a reduced overall cost. A further advantage was that no heavy machinery needed to be used to assemble the structure, as the units are easily moved and placed by hand.
The project was one of the first to be delivered to the PAS 2080 (Carbon Management in Infrastructure) standard. This involved tracking the project's carbon footprint throughout the preliminary design, detailed design, construction process, and operational stages to maximise both embodied and operational carbon – as well as overall cost for delivery.
This design innovation was recognised by the Institution of Civil Engineers (ICE) inaugural ICE Carbon Champions in September 2021.
The project also won the ‘Environmental Sustainability – Built Environment’ category at the 2022 Association of Consulting Engineers of Ireland (ACEI) Engineering Excellence Awards.
Key statistics
One of the first
projects to be delivered to the PAS 2080 standard.
ICE
Institution of Civil Engineers Carbon Champion
ACEI
Engineering Excellence Award Winner
