Topic
The main objective of LGLS was to design lightweight structures using ruled surfaces. Ruled surfaces play a major role in architecture and civil engineering like in the works of Vladimir Shukhov, Antoni Gaudí, Felix Candela, Santiago Calatrava and many others.
Ruled surfaces have a big advantage: they can easily be generated by moving a straight line through space. This fact already leads to typical strategies of fabrication like hot-wire cutting of extruded polystyrene for the formwork of concrete shells. On the other hand, they are statically efficient, especially in the case of skewed rule surfaces, which are very stable due to the generally negative Gaussian curvature. Last not least, typically the shapes using ruled surfaces are characterized by great elegance.
LGLS was both a summer school to enhance knowledge and abilities of the participants and a design space exploration of ruled surfaces, especially in lightweight construction applications:“The proof of the pudding is in the eating!”
Background
Shell bridge at the Footbridge 2017 Conference in Berlin. On the bridge: Juan Pablo Osman Letelier from the TU-Berlin-team, Chair of Conceptual and Structural Design. The prototype is 3 m long and the shell has a thickness of 5 mm. The flanks of the bridge are skew ruled surfaces.
During the recent research project “Thin-walled Concrete Structures with Line Geometry” (2015 - 2018), the teams of Prof. Mike Schlaich (TU Berlin) and Prof. Daniel Lordick (TU Dresden) developed tools and methods for the form-finding and dimensioning of components from ruled surfaces. The goal was to combine a mathematical approach with the requirements of engineering. The strategies have already been evaluated during a demonstrator project of a small footbridge, which was presented at the Footbridge 2017 Conference at the TU Berlin.