Design and mechanical analysis of 3D negative-stiffness curved domes with Bessel-functional profile

Abstract

The new-born Negative-stiffness (NS) metamaterial is famous for multi-stability and recoverability. However, it is difficult for beam structures, making up most of NS structures, to realize a satisfying improvement of mechanical properties, including stiffness and energy-absorption performance. The birth of NS dome structures figures out such problems, while the published dome structures with buckled-beam-based profiles cannot deform in accordance with the beam theory, resulting in loss of recoverability and stress concentration. In this paper, we put forward a novel 3D NS mechanical metamaterial constituted by the Bessel-functional curved domes (BCDs), whose profile is originated from the buckled circular sheet. Experiments and numerical studies are conducted, verifying better mechanical properties and distinct improvement in relieving stress and cycle stability. Upon the parametric analysis, this work also offers schemes for parameter selections of both mono-stable and multi-stable structures. Generally, the proposed NS dome unit could be an excellent candidate for an energy-absorption metamaterial by assembling.