Textile hybrid: based on isolated bent compression members
Master ´ s degree in Parametric Design in Architecture
3.1.4. FREI OTTO AND DAVID GEIGER
Frei Otto it is considered the pioneer in the tensile structures subject. Due to his wide research in natural principles applied in architecture, he achieve an interesting approach of design. The concept used for his famous buildings comes from the analysis of the soup films and funicular shapes. One of his famous statements was“ The less mass a structure needs to transfer forces, the better form is”. That is how in 1967 appeared a unique type of structure that the world had never seen, the German Pavillion, in the Expo at montreal( Figure A6). The structure cover an area of 8.000 square meters, the pavilion featured a large, steel mesh web suspended over eight steel masts.
Another master piece of architecture The Munich Stadium( Figure A7), designed by Frei Otto. He conceptualized a sweeping tensile structure that would flow continuously over the site imitating the draping of the swiss alps. The membrane is suspended from a multitude of vertical masts that allow for the dinamic draping curves of the surface. The final result is a roof with an undulating mesh. This project is one of the world’ s most innovative and complex structural systems that work with the premise of tension. This project was comisioned for the olimpic games in Germany in 1972.
Figure A6: German Pavillion. Expo 67”. Year: 1967
Other important progress was developed by the Engineer David Geiger, who designed the second larger span tensegrity dome for the Seoul’ s olimpic Stadium in 1988( Figure A8). The roof is a self suporting cable dome with a fabric cladding. For Geiger tension was a way to support textile roofs without the expensive mechainc system of inflate pneumatic structures. According with the Illinois regulations this structures support ten times more than the stablished level.
As we have seen above all these structures have the particularity of carry the external loads by pure tension, represented by cables or membranes, and compression, represented by arches or masts. These projects and breakthroughs are considered the main examples of tensile structures and tensegrity. All of them represent the previous stage of what would be later the hybrid active-form systems.
Figure A7: Munich Stadium. Year: 1972
Figure A8: Seoul ´ s Olimpic Stadium. Year: 1988
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