Comparison of the blast resistance of acoustic metamaterial panels and micro-perforated sandwich panels

How to conduct the coupled design for the sound absorption and anti-explosion properties of honeycomb structures is currently a challenge in the design of multi-functional structures. In the present study, the acoustic and blast response of two typical acoustic structures - acoustic metamaterial panels (AMP) and micro-perforated sandwich panels (MSP) - were experimentally investigated. Acoustic test results indicated that the designed AMP achieved a sound absorption coefficient of 0.78 at 800 Hz, while the MSP exhibited a coefficient exceeding 0.8 across a broad frequency band from 630 to 1600 Hz, demonstrating comparable effective absorption ranges. Subsequently, a series of blast tests were conducted to investigate their dynamic mechanical responses, including failure modes, deformation processes, and scaled-distance effects. Blast results revealed that the distance between the two structures from damaged to undamaged occurred between 250mm and 350mm. Analysis based on scaled distance showed that at a standoff distance of 300 mm, the AMP offered superior protective performance due to the integrity of its back face sheet. Conversely, at standoff distances of 350 mm and above, the MSP demonstrated better blast resistance owing to its smaller honeycomb core. Finally, a multifunctional evaluation model was established to quantitatively compare the overall performance of the two structures. These findings provide an experimental foundation for designing multifunctional metamaterials that integrate acoustic and mechanical performance.