A New Hybrid
Elastic gridshells braced by membranes
A new hybrid - Elastic gridshells braced by membranes
Deployable elastic gridshells are cost-effective lightweight structures making use of a rapid construction process, in which the geometry of the gridshell is obtained by bending an initially flat grid. This particular shaping process allows to save time during the erection of the structure, as the grid rods must not be bent individually but the grid can be shaped as a whole. Moreover, the assembling of the connections between the superposed rod layers of the grid can be done on the ground on a flat geometry, which results easier than connecting single elements on the air. Nevertheless, in order to be provided by sharing stiffness, the grid must be braced after the shaping process by additional elements as a third layer of rods or diagonal cables. The assembling of this bracing layer is usually time-consuming and requires additional supplies as cherry-picker or movable scaffolds. In this manner one of the great advantages- the rapid deployablity of elastic gridshells - is clearly reduced. In order to accelerate the construction process of deployable elastic gridshells, we propose to use covering textile membranes as stiffening and at the same time cladding surfaces. In this paper, we study the structural behaviour of an elastic hemispheric gridshell braced with a membrane layer. Different connection configurations between membrane and grid have been analysed and the results have been compared with traditional bracing systems.
Keywords: elastic gridshells, bracing membrane, hybrid structure, active-bending, finite-element-modelling
Christoph Gengnagel, Elisa Lafuente-Hernández