Stress Wave Mitigation Properties of Dual-meta Panels against Blast Loads

A dual-meta panel functioning as a sacrificial cladding is proposed and its blast mitigation capacity is investigated in this study. The proposed panel possesses the potential to generate bandgaps that target at a specific range of frequencies to stop stress wave propagating through the panel, leading to the favourable stress wave mitigation for structural protection. Aside from the unique stress wave manipulation capability, more energy can be absorbed by a combination of plastic deformation and local resonance. The effectiveness of the proposed panel is validated through numerical simulations. An analytical solution of wave propagation in an ideal meta truss bar is derived to validate the numerical model with good agreement. It is found that the proposed dual-meta panel exhibits an increase in energy absorption, a reduction in transmitted reaction force (up to 30%), and the back plate central displacements (up to 20%) compared to other conventional sandwich panels, e.g. sandwich panel with hollow trusses and solid trusses, in resisting blast loadings. In pursuit of optimizing the performance of the proposed panel, parametric investigations are also conducted to examine the influences of the plate thickness, boundary condition, and the blast load profiles including duration and intensity on the transient response of the proposed dual-meta panel.