In London, the 26-month closure of Hammersmith Bridge due to concerns about cracking in the infrastructure, as well as the ongoing RAAC concrete crisis, demonstrated that much of the UK’s current infrastructure is nearing, or has exceeded, its expected design life.
It is not economically or environmentally possible to simply replace bridges, so the only viable solution is to repair and strengthen them.
According to Nottingham University, polymer (FRP) composites are suitable for corrosion-damaged concrete structures, but they come with a high price, high environmental impact due to resin use, and poor fire resistance.
Consequently, a new generation of composites has been developed – Fibre-Reinforced Cementitious Mortar (FRCM) – that are compatible with concrete, breathable, resistant to fire, applicable on wet surfaces, sustainable, reversible, low carbon, and cost-effective.
The main goal of CARE 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.
In a statement, Dr Georgia Thermou, Assistant Professor in Structural Engineering at Nottingham University, said: “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.
“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 allows scientists across the UK to collaborate with leading institutions overseas.
Dr Thermou said: “Being able to establish connections and collaborate with other leading universities across the world is crucial when it comes to sharing knowledge and finding solutions that multiple countries can benefit from.”