Abstract
Man-made slender structures are known to be sensitive to high levels of vibration due to their
flexibility which often cause irreversible damage. In nature, trees repeatedly endure large
amplitudes of motion, mostly caused by strong climatic events, yet with minor or no damage
in most cases. A new damping mechanism inspired by the architecture of trees is identified
here and characterized in the simplest tree-like structure, a Y-shaped branched structure.
Through analytical and numerical analyses of a simple two-degree-of-freedom model,
branching is shown to be the key ingredient in this protective mechanism that we call
damping-by-branching. It originates in the geometrical nonlinearities so that it is specifically
efficient to damp out large amplitudes of motion. A more realistic model, using flexible beam
approximation, shows that the mechanism is robust. Finally, two bioinspired architectures are
analyzed, showing significant levels of damping achieved via branching with typically 30% of
the energy being dissipated in one oscillation. This concept of damping-by-branching is of
simple practical use in the design of very slender and flexible structures subjected to extreme
dynamical loadings.
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