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arXiv · 2508.10802

Snap-through time of arches is controlled by slenderness and imperfections

William Simpkins·Matthew G. Hennessy·Matteo Taffetani
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Abstract

Snap-through occurs in elastic structures when a stable equilibrium configuration becomes unstable, resulting in rapid motion towards a new and distinct stable state. While static analyses of snap-through are well documented, the dynamics of snap-through remain under-explored, particularly in structures with natural curvature. Using a combination of finite element simulations and multiple-scales analysis, we show that the snap-through dynamics of an arch under a central point load are controlled by its slenderness and imperfections embedded in the system. As the slenderness increases, the snap-through dynamics slow down, and the mode of snap-through changes from limit-point buckling to bifurcation buckling. When bifurcation buckling occurs, snap-through is preceded by an extended period of oscillatory behaviour. The duration of these pre-snap-through oscillations, and hence the snap-through time, is entirely controlled by imperfections in the system. Increasing the strength of imperfections dramatically reduces the snap-through time. Analytical expressions for the snap-through times are presented for limit point and bifurcation buckling. Our work suggests that natural curvature and deliberately introduced imperfections can be used to tune the snap-through dynamics of new functional materials.

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William Simpkins, Matthew G. Hennessy, Matteo Taffetani. 2025-08-14. Snap-through time of arches is controlled by slenderness and imperfections. https://arxiv.org/abs/2508.10802

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