Stronger concrete inspired by bones

Engineers at Princeton University in the US have created a new cement-based material inspired by the tough outer layer of human bones, which makes the material more resistant than traditional concrete.

In brittle construction materials used for buildings and civil infrastructure, strength ensures the ability to bear loads, while toughness helps resist cracking and the spread of damage. The new technique addresses these challenges by developing a material that is tougher than conventional options while still retaining its strength. This advancement could lead to more durable and resilient structures.

The team drew inspiration from cortical bone, the dense outer layer of human femurs known for its strength and fracture resistance. Cortical bone is composed of elliptical tubular structures called osteons, which are embedded in an organic matrix. This distinctive architecture deflects cracks around the osteons, preventing sudden failure and enhancing the concrete’s overall resistance to crack propagation.

Unlike traditional methods that reinforce cement-based materials by incorporating fibres or plastics, the Princeton team’s strategy focuses on geometric design. By precisely engineering the material’s internal structure, they significantly enhance its toughness without relying on external additives. This innovative approach allows for substantial performance improvements while maintaining material simplicity.

The design makes the material 5.6 times more resistant to damage compared to traditional options. By mimicking the structure of bone, the material can effectively resist cracking and avoid sudden failures, addressing the brittleness often seen in conventional cement products.

Photo: Princeton