Indentation and stability of woven domes. (March 2023) - Poincloux, Samuel
Abstract: Discrete domes are doubly curved structures comprising a network of beam-like elements. We study the mechanics of discrete domes made of ribbons woven in a pentagonal triaxial pattern. Experiments and finite element simulations are performed to characterize the mechanical response of each woven dome under indentation. The observed nonlinear response features force maxima, snap-through inversion, and non-monotonic evolution, leading to additional stable configurations. The dome's rest shape can be tuned continuously by designing the in-plane curvature of the ribbons and is then perturbed by adjustable clamped boundary conditions at their extremities. These control parameters are leveraged to smoothly and selectively modify the nonlinear features of the mechanical response, including multi-stability. Finally, we suggest a simplified model based on an elastica approximation to predict the stability of the inverted state successfully. The strong geometrical constraints imposed by the weaving pattern and the ribbons enable us to rationalize and tune the indentation response of these intriguing discrete structures. Graphical abstract: Highlights: The indentation of woven domes is investigated via experiments and FEM simulations. The rest shape of the domes is set by the in-plane curvature of the ribbons. The mechanical response can be tuned by varying the boundary conditions and rest shape. The mono- or bi-stability behavior is predicted using an elastica analogy.