Integrated analysis of kinematic form active structures for architectural applications: Design of a representative case study. (1st October 2016) - Puystiens, Silke
Highlights: A parameter study is performed through a simple linear elastic computational model. The study tries to improve the structural behaviour of kinematic fabric structures. We keep the membrane properly tensioned and avoid excessive stress concentrations. The chosen prestress and form-finding position influence the deployment behaviour. The path of deployment and material data effect the behaviour during transformation. Abstract: Today's architecture is characterized by a growing demand for flexibility and adaptability, allowing to adjust to meet the current needs. Both covering spaces for weather protection and improving energy performance of buildings ask for dynamic architectural solutions. The integration of lightweight technical textiles offers great possibilities for these kinematic structures, due to their inherently high flexibility. Unfortunately, until now, there is a lack of in-depth knowledge on the material properties of technical textiles, their structural behaviour during deformation and the use of available design tools. The inability to keep the fabric properly pretensioned in all deployment stages within the structure's limitations, obstructs the use of fabric structures for kinematic applications. In order to make a good design and analysis possible, we investigated the material properties of a standard polyester-PVC fabric and implemented these properties in a simple linear elastic computer model of a case study. Afterwards, we performed a parameter study to derive a set of conceptual design considerations for the kinematic prestressed fabric structure. The specified parameters to verify in the design process are (i) the boundary configuration in which form-finding is conducted (i.e. the reference state), (ii) the prestress levels and ratios, (iii) the control of the deployment and (iv) the used material parameters. The paper discusses how the computed model can serve as a design tool. An exhaustive preliminary study is essential to enhance the overall structural behaviour of the membrane structure in all stages of its transformation, within the application range, keeping the membrane properly tensioned and avoiding excessive stress concentrations. In a next step, a large-scale experimental model is set up, measuring the geometry, reaction forces and strains in the membrane. This model will serve as an experimental validation of the numerically obtained results.