Italian team builds self-healing, extra-tough concrete

New ultra-high durable concrete (UHDC) has been developed that withstands extreme conditions and is self-healing.

After water, concrete is the world’s most widely used material. It is a key component used in construction, whether for concrete flooring, roads or supports.

Professor Liberato Ferrara and his team at the Polytechnic University of Milan, Italy, set out to develop a new type of ultra-high durable concrete for use in extreme marine conditions and geothermic energy plants. Professor Ferrara said:

“These environments are among the most aggressive situations that you can have for concrete.”

The concrete the pressor’s team developed contains crystalline additives, cellulose nanocrystals and alumina nanofibers. Concrete cracks over time in harsh conditions, but in this case, crystalline mixtures react with water to form crystals that expand to fill cracks , making the concrete self-healing. Meanwhile, nanofibers add mechanical strength and make the concrete more durable.

The new concrete has been tested as a replacement for wooden rafts in mussel farms, on floating wind turbine platforms and in the restoration of an old water tower. These pilot applications of the UHDC have met the team’s expectations. The concrete can be manufactured in many locations using local materials.

The new UHDC is a sustainable material that can be crushed at the end of its life and recycled for use in new concrete.

Professor Ferrara estimates that thanks to the durability and self-healing element, the new UHDC will last up to 50 years in extreme environments before significant maintenance is required.