In spring 2010 the Chair of Structural Design launched its research activities on bamboo as a construction material. Current research activities focus both on applied science projects of bamboo and tent fabric shell structures such as bamboo composite elements as a material for the construction industry.
EiABC Workshop Structure
The bamboo shell project on EiABC campus caught the interest of the urban governance and decentralisation programme of giz. In collaboration with the Municipality of Awassa City, the Chair of Structural Design developed the concept of a pavilion designed from bamboo for the 2nd Ethiopian Cities Day in Awassa. Again the efficient system of a hyperboloid shell structure from whole and straight bamboo culms was chosen. The structure has a diameter of 11,5 m and a maximum height of 4,5 m. The roof structure consists of a radially oriented segments of tent fabric and bamboo beams that are biaxially prestressed by a centered ballast weight. A structural analysis of the shell system was carried out to determine all relevant loads in the structural members and details for further design. The pavilion was finally erected within two weeks on site with the help of local craftsmen.
Karsten Schlesier Lecture Hall
Currently the Chair of Structural Design is implementing the design of another large shell structure that will serve as a lecture hall with a capacity of 200 people at EiABC. The vertical support system is realized by a hyperboloid circular shell structure with a diameter of 21.0 m made up from straight bamboo culms. The structural roof system consists of 13 radially oriented bamboo truss beams with a maximum span of 12.0 m. The skin of the building along its outer perimeter is constructed by vertical steel panels. These panels are free to rotate about their central axis and can be opened to provide air and light to the interior or closed to act as a weather protection.
The research program on prefabricated modular bamboo composite elements as a construction material was established in March 2011 with the bamboo PPP program of ecbp/giz along with partners as Fortune Enterprise Furniture Ethiopia, the Fraunhofer Institute Germany and the Federal Mircro and Small Enterprises Development Agency Ethiopia. The research aims at developing structural members and modular systems from bamboo composite materials produced from local bamboo in Ethiopia.
Bamboo is a popular material in Ethiopia due to its local availability, its low costs, its high strength and its durability. Bamboo is a building material made by nature. It is appreciated for its natural appearance, it is environmentally friendly and can be produced sustainably. Bamboo has been used as a construction material in Ethiopian traditional habitats of various regions ever since. Nevertheless it is not well accepted in the modern construction context. But more than being used in interior designs, claddings or furniture, bamboo culms can be implemented as load bearing structural elements. The tensile and compressive strength of bamboo is up to ten times higher compared with timber. Due to its varying cross section along its length bamboo in its natural appearance is not as easy to classify as other construction materials. Hence purely tensile and compressive shell structures support the properties of bamboo culms as a building material most effectively.
Research objective and procedure
The main objective of the research is to introduce bamboo composite elements to the Ethiopian construction industry.
In detail the research aims at:
- the determination of material properties of local bamboo
- providing data sheets for bamboo composite elements
- setting up a catalogue of elements for structural members
- setting up a guideline of implementation for housing projects
Chair of Structural Design at EiABC,
Addis Ababa, Ethiopia