The cupola of the Palace of Exhibitions in Barcelona

Abstract

Recently two new halls have been opened within the Official International Fairs Enclosure in Barcelona. The central patio of one of them is covered by a cupola, whose design and constructive method differs from the conventional ones. Provisional wires cause a state of prestress to arise round the edges of the cupola skylights, when these cables are disconnected. These forces, applied to the boundary correspond to the loading conditions that are necessary if the cupola is to behave as a spherical shell, under ideal conditions. As this loading system cancels out in the shell all bending moments, which would otherwise arise, the possibility that cracks develop is avoided, and consequently the cupola is rendered waterproof. This design system also reduces the necessary percentage steel, and the concrete works under uniform, moderate, compression stresses, along tangents both in the horizontal and vertical planes. Thicknesses are reduced to the minimum. This article not only describes the original idea underlying this new design, but also the results that were obtained from tests on reduced scale models and the vicissitudes and stages of the construction process.