Concrete shells form-finding with surface stress density method

Concrete shells undoubtedly remain one of the genuine structural elements in contemporary architecture. However, designers have always been faced with difficulties in determining their shapes and, therefore, have developed analogies principally based upon physical models. In this paper, the authors propose a new form-finding method devoted to the numerical calculation of shell geometry and stress distribution. The mechanical approach requires isotropic stress tensors and is thus related to the surface stress density method already used for tensile fabric membranes. This process provides builders with an effective design tool and the possibility of generating various and suitable shapes in an interactive way. Several examples illustrate the efficiency and potential of the method.