HOW do you make a structure stronger? The answer, it seems, is to fill it with thousands of holes.
It might be seem counterintuitive, but holes can add resilience to a material by absorbing stresses or the energy of an impact. Researchers have come up with a formula for the ideal size and distribution of such cavities.
The approach is inspired by wood, a material that has evolved over millions of years to withstand the worst that weather can dish out, with the possible exception of lightning. In 2002, a team led by Julian Vincent at the University of Bath,…
