Optimal design of lightweight acoustic metamaterials for low-frequency noise and vibration control of high-speed train composite floor

•The characteristics of low-frequency noise and vibration in a high-speed train were investigated.•A lightweight and low-frequency acoustic metamaterial was optimised based on the MIGA.•The influence of installation positions of the acoustic metamaterial on noise control was analysed.•The composite floor with acoustic metamaterials achieved a 3.9 dB low-frequency noise reduction.