Past and future of grid shell structures

Abstract

Because of their original organic shape and the column free space that they provide, the design of grid shell structures challenges architects and structural engineers in more than one way. Very few grid shell building exist around the world. This scarcity may be explained by the level of innovation required in such fields as design technique; construction scheme, use of material... The goal of this paper is to unify the design work done on grid shells, to understand the evolution of the designs and to provide the reader with a sense of what awaits grid shell structures in the future. The construction of a timber grid shell starts from a flat, two dimensional wooden net, the three dimensional shell type structure is then achieved by pushing on the edges of this mat and gradually releasing the internal stresses at the joints to enable the shape to live and the structure to take its most adequate form. Only three wooden grid-shell structures exist world wide, by studying the way they work and behave, as well as the process that lead to the choice of such a structure, we'll understand how grid shell were born in the mind of architects and structural engineers.

(cont.) Even if the mechanism of grid shells is a very clever and well thought system, as wood remains a lively material, it can be subjected to degradation and deformation which as a result will damage the structure and attend to its integrity. Timber construction is also limited in terms of load carrying capacity. As grid shells have become more popular new solutions have been developed in terms of choice of material. Steel has already replaced timber in large span glass grid shell and the use of composite materials to benefit of the original construction scheme of timber grid shell is currently being investigated.