Meet the academic protecting bridges from climate change

“Sensors are essential to help increase the preparedness of structures to climate change,” says Dr Enrico Tubaldi of the University of Strathclyde, who is one of Connected Places Catapult’s new Researchers in Residence. His project involves exploring the impact that small devices fitted to bridges can have on protecting vulnerable infrastructure assets from the threat of flooding.

“Monitoring makes a huge difference in identifying structures that should undergo risk mitigation measures to increase their resilience from the threat of natural emergencies, such as floods and earthquakes,” he explains.

Enrico, a Reader in Structural Engineering, has developed strategies that use ‘probabilistic tools’ and machine learning to assesses the risk of scour – the removal of sediment from around bridge foundations due to increased river flows – from undermining older masonry arch crossings of waterways, which are prone to deterioration and possible collapse.

In 2021 he received funding from the Transport Research & Innovation Grants (TRIG) programme, delivered by Connected Places Catapult on behalf of the Department for Transport, to develop a low cost, real-time monitoring platform that uses measurements of the depth of water and surface velocity of flow to determine the extent of bridge scour on several structures supporting roads and railway in Scotland.

From earthquakes to floods

Enrico’s professional focus pivoted towards mitigating the risk of flooding undermining structures, after arriving in the UK from his birthplace of Italy. His academic career began in 2006 in the field of earthquake engineering as a PhD student and then a post-doctoral researcher at the University of Marche in the centre of the country. He developed novel strategies for carrying out seismic reliability assessments of structures and systems to protect buildings from the impact of tremors.

His interest in earthquake engineering began as a high school student in 1997 when he experienced first-hand a strong quake which caused extensive damaged to many older buildings throughout the region, killing 11 people.

Enrico’s fascination with the subject was galvanised in 2009 following a further large earthquake in the region when he was studying in America.

He later joined the University of Camerino to become a lecturer in structural engineering, before relocating to the UK at the end of 2014 to join Tun Abdul Razak Research Centre in Hertfordshire, to research the use of rubber bearings for isolating structures from earthquake-induced ground shaking.

Enrico also explored the impact of earthquake tremors on reinforced concrete buildings, and – in parallel to his current focus on flooding – continues to help develop rubber-based technologies to reduce the impact of shocks on buildings, to help keep them standing. Enrico recently spent time in a laboratory in North Macedonia testing new systems on a ‘shaking table’ which mimics the effects of earthquakes on large scale prototypes. He and colleagues are looking to commercialise the technology soon.

His move to the UK came about after receiving a prestigious Marie Curie European Postdoctoral Fellowship. “One of the conditions of the fellowship was relocating to another country, and another was that I had to choose a different topic to study; so I moved from earthquakes to floods.”

This switch coincided with the collapse of the historic Pooley Bridge in Cumbria during a heavy storm and rising waters; with the cause determined to be scour and erosion of the riverbed.

Enrico joined Imperial College London as a research fellow, assessing the flood vulnerability and risks of masonry arch bridges. “I have always been fascinated by masonry bridges and their heritage, and thinking of ways to preserve them. They are the most vulnerable to the effects of flooding, including problems with scour around the foundations,” he explains.

“I was able to exploit much of the knowledge I had gained in the field of earthquake engineering and transfer it to the problem of flooding. In both cases, we are talking about events that are characterised by significant uncertainties in terms of their timing and intensity. I also realised that there were gaps in understanding flood risk assessment for bridges, even though floods represent a critical hazard.”

Enrico was introduced to Professor Daniele Zonta from the University of Strathclyde who was also working on the problem of bridge scour, but from a different perspective: structural health monitoring. A colleague put the two men in touch, and it turned out the university was looking for a lecturer. Enrico took up the post in 2017 and has gone on to become a Senior Lecturer and most recently a Reader in Structural Engineering at Strathclyde.

Enrico and Daniele worked together to develop strategies for monitoring scour around the piers of bridges crossing waterways, and a collaboration with Transport Scotland has led to the deployment of several sensors for scour and flow monitoring on three bridges south of Glasgow.

Enrico is also exploring how satellites can be used to monitor the deterioration of bridges, and is working with an Italian collague, Carmine Clemente, on a project funded by the European Space Agency exploring the use of satellite data to monitor vibrations on structures. A change in frequencies recorded could, he explains, indicate damage or degradation that warrants further inspection.

Research impact through Catapult funding and support

Enrico is grateful for his TRIG funding which allowed him to buy components for several sensors, develop the technology further and test them; as well as spend time developing models for converting the information received from the sensors into estimates to determine scour risk.

“Connected Places Catapult also provided me with several useful contacts at a senior level and others working on similar topics in the areas of bridges and flooding,” he says.

For his new Researcher in Residence appointment, Enrico is further exploring low-cost devices for monitoring the structural integrity of bridges in relation to scour, and modelling vulnerabilities on the transport network. He is also working alongside the Climate Resilience Demonstrator to develop digital twins of structural assets, leveraging his experience in a project funded by National Highways on improving risk assessment and prioritisation processes for the management of scour at structures.

He adds that bridges are important connectors not just for people and vehicles but utility services too. “Very often a bridge carries power cables and telecoms, so when the structure is damaged it could have a knock-on effect for networks other than transport.”

Enrico says the impact of climate change is becoming increasingly evident with a larger number of floods and “more extreme events occurring at a higher rate”. Coupled with a lack of investment in maintaining bridges – as highlighted by transport group the RAC Foundation – and the outlook for our historic structures is uncertain.

“Hopefully my research will help transport agencies to make better informed decisions about where to intervene and spend money carrying out maintenance and risk-mitigation actions,” he says. “I hope to reach a wider audience to explain about the need for continual monitoring of assets, and to deploy the technology I’m helping to develop at a larger scale.”

Find out more about Connected Places Catapult’s Researchers in Residence programme and join our Academic Network.