We investigate the combined influence of shallowness and geometric imperfection on the pressure-induced buckling behavior of clamped spherical shells. The buckling phenomenon in spherical shells has gained significant interest in diverse fields, such as soft robotics and biomechanics, due to its distinct and drastic shape morphing characteristics. However, a notable discrepancy between analytic solutions and experimental results persists, necessitating further research to comprehend the buckling behavior of spherical shells with varying shallowness and geometric imperfection. To address this gap, we experimentally investigate the buckling of clamped spherical shells under uniform pressure while controlling the shell shallowness over a wide range. The experimental results validate finite element simulations, enabling analysis of the variation in buckling pressure and behaviors by manipulating the shell shallowness and geometric imperfection. Our analysis reveals decaying oscillatory variations in the buckling strength versus the shallowness curves, eventually converging to stable buckling strength for sufficiently deep shells. Moreover, these curves exhibit changes in level and shape with varying geometric imperfection. We also observe non-axisymmetric buckling modes in shells with small geometric imperfection and specific shallowness ranges. Through parametric studies, we identify the geometric conditions influencing the buckling behavior, particularly the non-snap-through criteria and non-axisymmetric buckling modes. This comprehensive investigation sheds light on the interplay between shallowness and geometric imperfection affecting the buckling behavior of clamped spherical shells. The findings contribute to a deeper understanding of shell buckling phenomena and have implications for various shell design applications.

我们研究了浅度和几何缺陷对夹紧球壳压力诱发屈曲行为的综合影响。球壳中的屈曲现象由于其独特且剧烈的形状变形特征而在软机器人和生物力学等多个领域引起了极大的兴趣。然而，解析解和实验结果之间仍然存在显着差异，因此需要进一步研究以理解具有不同浅度和几何缺陷的球壳的屈曲行为。为了解决这个问题，我们通过实验研究了均匀压力下夹紧球壳的屈曲，同时在大范围内控制球壳浅度。实验结果验证了有限元模拟，能够通过操纵壳体浅度和几何缺陷来分析屈曲压力和行为的变化。我们的分析揭示了屈曲强度与浅度曲线的衰减振荡变化，最终收敛到足够深的壳的稳定屈曲强度。此外，这些曲线表现出水平和形状的变化以及不同的几何缺陷。我们还观察到具有小几何缺陷和特定浅度范围的壳中的非轴对称屈曲模式。通过参数研究，我们确定了影响屈曲行为的几何条件，特别是非突跳准则和非轴对称屈曲模式。这项综合研究揭示了影响夹紧球壳屈曲行为的浅度和几何缺陷之间的相互作用。这些发现有助于更深入地了解壳体屈曲现象，并对各种壳体设计应用产生影响。