A contemporary shell structure | Giada Schioppa

The word “shell” indicates a three dimensional curved surface in which one dimension is significantly smaller compared to the other two, just like in a “shell’s egg”. It is more efficient than other structural systems because its resistance and forces depend on its shape and viceversa. Working and modelling the shape means projecting its structure.  Due to the complexity of the subject, this type of structure was knowingly used since the mid 1900-s. Studies to use less material helped the research to build lighter and more efficient shells: “gridshell structures”, in which the continuous surface is replaced by a grid made of bars and panels. 

After a depth study of the theory to learn and discover more about this interesting structural system, the aim of this work is to practice and to simulate the project of a contemporary shell structure to cover an Aquatic Centre in Italy, on the East Coast, in Tortoreto Lido (TE). Located close to the beach in an empty area among a bike path on the east, a training football camp on the west, a camping on the south, the project is developed considering a direct connection to the waterfront. Its shape is inspired by the natural landscape: it evokes the undulating hills of the hinterland of Central Italy. The section is full of energy and simulates the waves of the sea. The shape is investigated thank to the study of three plans at the same time. After drawn the silhouette of the roof, the model is transformed from static to dynamic, using the plug-in grasshopper. So it is possible studies to optimise it looking for the best shape. At the end, the building appears as a kind of a reptile stranded on the coast that hides and protects various leisure and recreational activities. 

Form finding is a forward process in which parameters are explicitly and directly controlled to find an “optimal” geometry of a structure, which is in static equilibrium with a design loading. So, shape’s optimization is investigated assuming Z(m) (that measurers heights ‘points) as the variable parameter, while X(m) and Y(m) fixed.  Points can move along the Z axis, within intervals established by architectural requirements.

It is possible observing various displacements and different strain energy‘s values: the best configuration is the  one with the smallest values, thanks to the famous Clapeyron's theorem: «In the linear theory of elasticity the potential energy of deformation of a body, which is in equilibrium under a given load, is equal to half the work done by the external forces computed assuming these forces had remained constant from the initial state to the final state».