CAD-integrated Parametric Design Cycle for Structural Membranes

The design cycle of membrane structures consists of three interactive and highly non-linear disciplines. Formfinding is performed in order to find a geometry that allows the prestressed structure to carry loads through tension only. Once a formfound geometry is set, structural analysis needs to assess the structure's safety and usability. The most challenging step is the cutting pattern generation, which aims at finding the planar pieces which can be elevated to build spatial membrane structures with a minimum deviation from the desired shape and prestress state.<br/> Isogeometric B-Rep Analysis (IBRA) allows the designer to perform analyses on the original CAD model without leaving the CAD environment. High quality is ensured for the geometry and the mechanical approximation by using Non-Uniform Rational B-Splines (NURBS). Additionally, the topology information of multipatches can be transferred to the analysis in order to enrich the design space. Trimmed and coupled surfaces can thus be included in the analysis. Parametric models allow the designer to examine a large variety of geometrical and mechanical entities with one model.

The advantages of the CAD-integration with IBRA for the highly interactive design of structural membranes are shown in this contribution.