A design based on insect exoskeletons has helped a team of civil engineering researchers crack the balance between strength and damage tolerance in cement.

The project was led by Wenhui Duan, a professor in structural engineering at Monash University, and described in an article published in Nature Communications last month.

The tradeoff between a material’s strength – its ability to bear weight – and its ability to tolerate damage is a classic engineering dilemma.

High-strength materials are usually stiff and don’t change shape when loaded with weight, explains Wei Wang from Monash University, who is co-first author on the study.

“However, damage tolerance requires the material to deform under loading in order to dissipate energy.”

So-called ‘brittle materials’, like concrete, are typically strong but easily broken. If only a small area of concrete becomes cracked, the whole structure can quickly fail.

As in so many things, though, nature has already found a successful way to balance these competing factors.  

“If we regard evolution as a process of optimisation, that optimisation has been happening for millions of years,” says Wang’s co-first author Shujian Chen, a lecturer in structural engineering at the University of Queensland.

An insect’s exoskeleton – in particular, its segmented legs – is both strong and capable of absorbing a lot of energy, making it damage-tolerant.

Keep reading on CosmosMagazine.com