Study on a Novel Dual-Layer Graded Honeycomb Metamaterial for Bridge Anti-Collision Structures

With the rapid expansion of bridge infrastructure and the increasing frequency of ship-bridge collision accidents, traditional anti-collision measures have exhibited limitations in dispersing and absorbing impact energy. This study proposes a novel duallayer composite gradient mechanical metamaterial for impact mitigation based on the honeycomb configuration within a bridge anti-collision structure. The structure comprises two functional units. The upper layer is a high-porosity energy-absorbing layer, which achieves efficient and gradual release of the initial impact energy through a gradient distribution of porosity and wall thickness. And the lower layer is a high- stiffness support layer that provides the necessary structural support and impact resistance, ensuring stability of the whole structure under extreme loads. By the welldesigned composite gradient honeycomb configuration of the proposed mechanical metamaterial, the anti-collision structure acquires exceptional mechanical properties such as lightweight, high energy absorbing efficiency, and enhanced impact cushioning performance. This research investigates a feasible design of the dual-layer graded honeycomb metamaterial through theoretical modeling and numerical simulations. By conducting dynamic compression and drop hammer impact simulations, the dynamic impact response and energy-related performance are comprehensively studied. Results indicate that the proposed dual-layer composite gradient mechanical metamaterial can significantly reduce the impact load, enhancing both the energy absorption efficiency and safety, therefore advancing the construction of the bridge anti-collision structure.