Shape Restoration of Deformed Egg-Shaped Single Layer Space Frames

Egg-shaped single layer space frame structures have many applications among space structures. One of the advantages of egg-shaped geometry is its low ratio of surface area to volume as compared with other common geometries. They provide a unique solution for covering large spaces that seat on substructures, or as load bearing structures. They are economical and aesthetically pleasing in appearance as well as the architectural requirement, in which tolerances of structural shape under changing service conditions are vital. Due to the influence of load and fatigue, the outer face of the egg shaped single layer space frames may suffer big deformation, which leads to a significant potential undesired appearance of the shape. In this situation, the displacements may need to be reduced or eliminated. In this paper, two trials were made to static shape control of the structure to restore or limit displacements according to the desired target. In both attempts, the target displacement was the same but location of the actuations was different to show its impact of the efficiency of the work. The improvement was done via controlling nodal displacements of the theoretical model of the Egg-shaped single layer of space frame structures. This can be done through using a relatively simple and direct method previously derived by the author, via calculating required length actuations within a single formulation.