Underwater sound absorption characteristic of the rubber core sandwich structure with funnel-shaped cavities reinforced by carbon fiber columns

•A multi-functional structure is designed for pressure resistance and acoustic stealth.•Underwater sound absorption property of the structure is studied for the first time.•The acoustic propagation experiment is conducted on the manufactured sample.•Sound absorption mechanisms of the structure are revealed via parametric analyses.•The experimental data can be used as a benchmark result for future researches.