Computational Design and Simulation of Bending-Active Auxetic Structures

Abstract

The paper investigates the potential application of auxetic structures in architecture through the combined use of computational design and Additive Manufacturing (AM) methods. This class of materials expresses an interesting behavior related to the unusual characteristics of a negative Poisson’s ratio where, as opposed to other materials, the act of stretching causes shrinking and the act of compressing results in bulging. The work explores a new research and design field where different auxetic patterns are studied to support a form-finding process of bending-active synclastic gridshells. Computational methodologies have been implemented to preview the dynamic behavior of such structures through form-finding simulations based on Particle Spring Systems. Principles for the design and fabrication of auxetic gridshells are studied through multiscale AM. This is employed to produce scaled models useful for a direct understanding of the auxetic behaviour, as well as to envision the production of mega-structural auxetics with optimized microstructural organization. The understanding of their bending capacity has been explored with the use of variable infill patterns informed by structural analysis. Finally, a design for a full scale gridshell prototype is proposed along with a novel concept for its on-site additive manufacturing.