Engineering news
“Soaring” temperatures and rebounding traffic levels post-Covid are increasing the speed of damage to critical infrastructure, according to the team from the University of Nottingham, which is collaborating with Luleå University of Technology in Sweden on a new project aimed at tackling the problem.
The recent 26-month closure of Hammersmith Bridge due to cracks, and the ongoing RAAC concrete crisis, demonstrate that much of the UK’s current infrastructure is nearing – or has exceeded – its expected design life, the researchers said.
It is not economically or environmentally possible to simply replace bridges however, they added, meaning the only viable solution is often to repair and strengthen them. In the UK alone, the cost of repairing bridges due to corrosion damage is estimated to cost millions of pounds.
Non-corrosive fibre-reinforced polymer (FRP) composites are “excellent” strengthening systems for corrosion-damaged concrete structures, the researchers said, but they come with their own drawbacks – including high price, high environmental impact due to resin use, and poor fire resistance.
As a result, a new generation of composites has been developed – fibre-reinforced cementitious mortar (FRCM). FRCMs are compatible with concrete, breathable, resistant to fire, applicable on wet surfaces, sustainable, reversible, low-carbon, and cost-effective – at least 30% cheaper than FRPs – the Nottingham announcement said.
The main goal of the Climate Adaptation for REsilient Bridges (Care) project is to find durable and sustainable solutions by investigating how different temperatures, and accumulated damage caused by repeated load cycles, affect the performance of FRCM composites when used in bridge strengthening.
“Although experimental evidence has demonstrated the efficiency of FRCMs when it comes to improving undamaged structures, it has not been tested on more complex structural systems with accumulated damage or that have been subject to seasonal temperature changes,” said Dr Georgia Thermou, assistant professor in structural engineering at Nottingham.
“Our experiments and simulations will generate new knowledge, which will benefit the construction and composites industries by providing a sustainable solution for strengthening bridges and creating a new market for composites respectively. Additionally, it will greatly benefit society by providing safe and sustainable infrastructure that will contribute towards a greener economy and, crucially, minimise bridge closures or even failures.”
The Care project has been funded by the Royal Society as part of its International Exchanges scheme, which helps scientists in the UK collaborate with institutions overseas.
Dr Jaime Gonzalez-Libreros, associate senior lecturer at Luleå, said: “Our aim is not just to extend the lifespan of existing structures, but to do so in a way that is economically viable and environmentally responsible. This project is a step forward in creating a sustainable future for our communities.”
Want the best engineering stories delivered straight to your inbox? The Professional Engineering newsletter gives you vital updates on the most cutting-edge engineering and exciting new job opportunities. To sign up, click here.
Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.