Madrid – Researchers from several Spanish universities have revealed the hidden mechanisms that explain why some bridges, specifically those of steel lattice, resist and do not collapse when they are affected by catastrophic events, and how they can even resist major loads to those that support in normal conditions.
These ‘hidden mechanisms’ have been revealed by researchers at the University University of València (UPV) (east of Spain) and the University of Vigo (north), which have compared the functioning of iron bridges with the cobwebs, which are able to adapt and continue to catch prey even after having suffered damage and of having lost some of their threads; Today they publish the results of their work in Nature magazine.
The engineer and researcher José Miguel Adam, of the UPV Concrete Science and Technology Technology Research Institute, explained that the construction of iron bridges was very common between the end of the 18th and early twentieth century, and has observed that many of them are still in service and fully operational, especially in rail lines.
Adam, coordinator of the ‘Pont3’ project, has detailed to EFE how by performing tests in the laboratories they verified that latent resistance mechanisms were activated that revealed their robustness, and how they simulated more than two hundred failures of different elements until corroborating that the bridges “resisted much more than we expected, because mechanisms that we so far ignore were activated”.
Increasingly intense and unpredictable natural events
Bridges are critical elements of transport networks, and their collapse can have very serious consequences, including fatalities and economic losses that can reach millions of euros for each closing day, the Polytechnic University has indicated in a press release released today.
Belén Riveiro, a researcher at the Technologies, Energy and Industrial Processes Research Center at the University of Vigo, has underlined in the same note the importance of these structures not collapse due to a local failure and before the increasingly intense and unpredictable natural events and environmental changes that are accelerating the deterioration of the bridges.
It was not clear so far why some initial failures of certain elements spread disproportionately in some cases, while in others they barely affect the functionality of these constructions, but researchers have revealed the secondary mechanisms that allow these structures to be more resilient and not collapse.
Their conclusions, they have assured, provide new keys to the design of safer bridges against extreme events and will also serve to improve the monitoring, evaluation and reinforcement strategies of existing ones or to redefine the robustness requirements of iron structures.
Extend the life of old iron bridges
José Miguel Adam has specified to Efe that his findings reveal which mechanisms or parts of a new bridge should work in more detail to be activated in case of an eventual local failure, and in the case of existing ones where attention should be focused or inspections or what elements would have to be reinforced to activate those latent mechanisms of resilience.
In his opinion, this technology would even recover many bridges that today are in disuse or prolong the useful life of thousands of constructions, many of which rose more than a hundred years ago and could continue to operate with security guarantees if appropriate reinforcement measures are implemented and that have been discovered with this work.
The ‘Pont3’ project is funded by the Ministry of Science, Innovation and Universities, and the starting point of the work that Nature publishes today starts in ‘Leonardo’ scholarships that the BBVA Foundation granted to Belén Riveiro (in 2021) and José Adam (in 2017) to study this type of structures and the resistance of the constructions against local failures.