  Gridshells are defined as structures that have the shape and rigidity of a
double curvature shell but consist of a grid instead of a continuous surface.
This study concerns those obtained by elastic deformation of an initially flat
two-way grid. This paper presents a novel approach to generate gridshells on an
imposed shape under imposed boundary conditions. A numerical tool based on a
geometrical method, the compass method, is developed. It is coupled with
genetic algorithms to optimize the orientation of gridshell bars in order to
minimize the stresses and therefore to avoid bar breakage during the
construction phase. Examples of application are shown.
