Initial Bamboo Investigations

Ok, bamboo is now on the menu. After referring to western building techniques and technologies, I would like to investigate ways of integrating bamboo into the project. I have heard how it is often used for flooring scaffolding and furniture, but can it be used to build an elegant and expressive building?

Upon initial investigations, the answer is YES! People from all over the world and from different cultures are approaching bamboo use and construction in numerous ways.


I found this image of a bike frame using bamboo on the internet and wanted to know more:













Although it is a type of grass, you could intepret bamboo as having similar compressive properties to timber. The the centre hollow and circular in section, it has a high I value or stiffness relative to its weight.


In the photo, the bamboo is essentially used in compression, with metal connections that sheath the bamboo into the correct location. The thickness of the bamboo relate to the loads required on each element in the frame. You can conclude that the wider the diameter of the hollow section, the more compressive load the material can take and distribute to the ground.

http://en.wikipedia.org/wiki/Nomadic_Museum

I found this link related to a temporary exhibition pavilion deisgned by Shigeru Ban. Using transport shipping containers, tensile materials and bamboo, a huge pavilion was created with surprisingly intimate spatial qualities. The rough bamboo elements were used for the roof frames as well as the walling system.

http://www.michaelmcdonough.com/projects/spec/bambridge.php4


I also came across this project for a bamboo bridge designed by Michael McDonough






















The notion of tensegrity is mentioned as the prevailing idea within the project. Coined by Buckminster Fuller, each element within a tensegrity frame either performs in tension or compression ONLY. In this instance the bamboo is being used for compression with tensile cables.

Shigeru Ban often uses bamboo for projects. This is a link to his website:

http://www.shigerubanarchitects.com/



















As well as using paper tubes, his office also uses bamboo elements that are beautifully expressed.




These images of the Japan Pavilion from Expo 2000 show a lightwieght bamboo structure with a lightweight roofing material. I have noticed that it is not often used to support other heavy elements, as it would create too much compressive force in the top of the tube. This would cause it plastically deform which it would not recover from. See sketch below:


Bamboo is best used where there is an axial load. In other words, where a force acts parallel to its length. The idea is to minimise the use of bamboo acting as a beam or a connector. In the sketch, you can see that the force acting on the sample (not parallel) is forcing the top of the bamboo into compression and the bottom into tension. Bamboo like timber does not perform well in tension so it is best to be avoided.





Another interesting thing to note about the way that bamboo is used in this project is the method of construction. The images to the side show that a huge number of hydraulic rams are used to form the shape. Then the bamboo elements are fixed in place with the Earth. This is really not possible for the East Timor project as this would lead to numerous logistics requirements and an unrealistically expensive construction.




Given the supposed abundance of bamboo in East Timor, further investigations are needed into how to use it.

I have attached a link to a PDF of examples of bamboo architecture and some of the architects and engineers involved:

http://www.koolbamboo.com/Modern%20bamboo%20architecture.pdf