Building up bamboo | MIT News

Building up bamboo | MIT News



MIT scientists, along with architects and wood processors from
England and Canada, are looking for ways to turn bamboo into a
construction material more akin to wood composites, like plywood. The
idea is that a stalk, or culm, can be sliced into smaller pieces, which
can then be bonded together to form sturdy blocks — much like
conventional wood composites. A structural product of this sort could be
used to construct more resilient buildings — particularly in places
like China, India, and Brazil, where bamboo is abundant.



Such bamboo products are currently being developed by several
companies. The MIT project intends to gain a better understanding of
these materials, so that bamboo can be more effectively used
structurally. To that end, MIT researchers have now analyzed the
microstructure of bamboo and found that the plant is stronger and denser
than North American softwoods like pine, fir, and spruce, making the
grass a promising resource for composite materials.



“Bamboo grows extensively in regions where there are rapidly
developing economies, so it’s an alternative building material to
concrete and steel,” says Lorna Gibson, the Matoula S. Salapatas
Professor of Materials Science and Engineering at MIT. “You probably
wouldn’t make a skyscraper out of bamboo, but certainly smaller
structures like houses and low-rise buildings.”



Gibson and her colleagues analyzed sections of bamboo from the inside
out, measuring the stiffness of each section at the microscale. As it
turns out, bamboo is densest near its outer walls. The researchers used
their data to develop a model that predicts the strength of a given
section of bamboo.



The model may help wood processors determine how to assemble a
particular bamboo product. As Gibson explains it, one section of bamboo
may be more suitable for a given product than another: “If you wanted a
bamboo beam that bends, maybe you’d want to put the denser material at
the top and bottom and the less dense bits toward the middle, as the
stresses in the beam are larger at the top and bottom and smaller in the
middle. We’re looking at how we might optimize the selection of bamboo
materials in the structure that you make.”



Gibson and her colleagues have published their results in the Journal of the Royal Society: Interface.