A New Kind of Concrete Can Repair Itself

Believe it or not, concrete is getting harder.

A team of scientists has designed a new ultra-resistant type of concrete material that can repair itself, according to a recent press release.

The new concrete possesses 30% more durability than conventional top-of-the-line concrete, which means fewer cracks forming, and when they do happen, it can even repair itself.

From passive to 'active' protection with concrete

"These properties are possible mainly thanks to the design of the mixture and use of components such as crystalline additives, alumina nanofibers and cellulose nanocrystals, which are capable of improving the ability of the material to repair itself", said Researcher Pedro Serna at the Institute of Concrete Science and Technology (ICITECH), which is part of the Universitat Politècnica de València, in the press release. Another key feature that enables the new material to surpass rival ones is the far lower frequency of conventional and extraordinary maintenance work needed. The material can last far longer than typical limits, which are roughly 50 years. This is especially useful for infrastructures that endure aggressive environmental stresses, like constructions near the sea, or geothermal power plants.

"In this project we are demonstrating how the durability of cementitious materials becomes a characteristic that can be designed through the synergy between the composition of the material and the structural conception," said Marta Roig Flores, another researcher at ICITECH, in the press release. "We have designed and are testing new cementitious compounds with the capacity for structural self-repair in the cracking phase, which is the usual state faced by a reinforced concrete structure". This represents a shift in the design philosophy of durability, from a notion of material as a substance of passive protection against external calamity, to one of "active" protection.

Real-time data on the new concrete's performance

While validating the material, it was employed in the construction of six large-scale pilot structures that are presently under evaluation amid real-world structural operations. Two of them are in the Valencian Community, with another two in Italy, and one each in Malta and Ireland. These physical structures are continually monitored with UPV technology, leveraging an extensive network of sensors supervised by an IDM Institute team. This enables engineers to verify the new ultra-strong concrete's performance as the days turn into weeks and years.

As a test system, it has self-contained sensors arranged into an electronic tongue that offers real-time and ongoing information on the durability of the structure. "These data allow the experts in the field to verify the good condition of the structures, or, as the case may be, to adopt the necessary measures to prevent the damage from worsening, by using the most appropriate, economical, and less affected method of protection or repair on the operation of the structure", said Juan Soto, another IDM Institute researcher. This new material, combined with real-time data of its unique performance profile, represents a significant window into the future of construction, architecture, and could lead to future enhancements in the industry as the world begins to confront the ecological toll of materials production.