Whatever else Brexit has done for the social, economic and cultural future of the United Kingdom, it’s excellent fuel for imagining hellish dystopias. The weekend was a time for panicked mourning. Monday is a time for making plans. And so I present to you: towers made of bone.
According to researchers at the University of Cambridge, the cities of the future will have to adapt to ever-expanding populations, as well as an increasing need to reduce carbon emissions. Materials such as concrete and steel are responsible for up to 10% of worldwide carbon emissions, so engineers have to come up with new, energy-efficient ways to build.
One path of research, outlined by bioengineer Dr Michelle Oyen, of Cambridge’s Engineering Department, is to build with artificial bone. Lab-made composites of proteins and minerals that mimic the structures of human bone are currently used for medical implants, but the idea is that this can be scaled up to be used as building materials.
“What we’re trying to do is to rethink the way that we make things,” says Oyen. “Engineers tend to throw energy at problems, whereas nature throws information at problems – they fundamentally do things differently.”
Oyen’s biomimetics lab, funded by the US Army Corps of Engineers, currently makes artificial bone and eggshell. The latter might not sound like the ideal building material, but is incredibly tough in proportion to its thinness. To make the artificial biostructures, minerals components are “templated” onto collagen.
“One of the interesting things is that the minerals that make up bone deposit along the collagen, and eggshell deposits outwards from the collagen, perpendicular to it,” says Oyen. “So it might even be the case that these two composites could be combined to make a lattice-type structure, which would be even stronger.”
One particularly interesting quality of bone, mentioned by the researchers at Cambridge, is its ability to self-heal. This is apparently something scientists want to mimic in man-made structures. It certainly captures the imagination: picture a city of self-repairing bone towers – splints and plaster casts wrapped around bombed-out houses.
Welcome to bone town
Comparisons to a nightmarish, post-Brexit corpse city are, of course, unintended. If anything, the city of bone and eggshell laid out by Oyen is utopian in its aspiration to harness natural materials for future cities. Indeed, human civilisation has a long-standing relationship with another natural material – wood. Dr Michael Ramage from Cambridge’s Department of Architecture believes that timber is vastly underused as a building resource.
“If London is going to survive an increasing population, it needs to densify,” says Ramage. “One way is taller buildings. We believe people have a greater affinity for taller buildings in natural materials rather than steel and concrete towers.”
“The material properties of bone and wood are very similar,” adds Oyen. “Just because we can make all of our buildings out of concrete and steel doesn’t mean we should. But it will require big change.”