Bracing elastic gridshells in their final form remains a time consuming step with a lot of handiwork. The lack of alternative to membrane covering is also an important limit to the development of such technology. The proposed experiment tries to tackle both issues through a novel concept of hybrid structural skin made of an elastic gridshell braced with a concrete envelop. The idea is to use the gridshell as formwork for the concrete and to insure a connection between the thin concrete skin.
The Ephemeral Cathedral of Créteil (Paris, France) is a gridshell structure made of composite materials. Built in 2013, this religious edifice of 350m2 is a temporary church meant to gather the parishioners during the two-years renovation of their permanent cathedral. This large-scale prototype represents a first in the building industry, which still shows excessive apprehension for the use of non-traditional materials such as composites, especially when it comes to structural applications. Based on a previous successful experience the gridshell was prefabricated and erected by the parishioners themselves.
In June 2011, the Solidays music and cultural festival welcomed a world first in the field of composites : a gridshell-type structure open to the public of a size that has never been reached before. The result of the work of 12 architecture and engineering students, a leading-edge research laboratory and several companies, this project, in support of the fight against AIDS, created much enthusiasm and opened the way for a large number of applications in the construction industry.
When looking a catapult that is ready to throw a stone, one can observe that there is very little displacement of the beam when the stone is put on the catapult. This is due the fact that the rope act as a column and takes the load of the stone. The rope has been prestressed by the bending energy stored in the wooden beam. By adding weight on the catapult the rope will lose tension. The same concept can be used to shorter the span of a beam or a bridge.
Overview of our prototypes