"Bamboo is close to an ideal structural material." This statement by Neil Thomas during his talk at Bamboo U, which took place in November 2017 in Bali, really caught my attention. Neil is the founding director of atelier one, a London office of structural engineering, whose outstanding projects include stage and scenography for the Rolling Stones, Pink Floyd, and U2; art installations by Anish Kapoor and Marc Quinn; the Gardens by the Bay, in Singapore, among many others. From the last few years, the engineer has exhaustively studied about bamboo, its structural properties and its most diverse potential.
According to him, bamboo is close to the ideal structural material, beginning with its tubular shape. An open section, such as a channel, is weaker than a closed one because the edge can bend much more easily. Just think of a sheet of paper and how it becomes stronger when we roll it up like a tube, preventing it from bending so much.
In addition, it has another feature that improves its resistance. The bamboo culm has longitudinal fibers that span the entire lenght, called vascular bundles. Closer to the exterior of the culm wall, these bundles have a higher density, making them stronger. So, the stronger part of the section is further away radially from its centroids, making the overall section stronger. And this is the main difference compared to a wooden trunk, which has its strongest material in the center of its section. Another peculiarity is its speed of growth. Unlike hardwood, which can take more than 30 years to be exploited, bamboo can be cut and used between 3 to 5 years, then growing again.
