Dynamic response of self-locked energy absorption system under impact loadings

•The impact response of self-locked systems is studied by impact experiment and simulations.•A one-dimensional theoretical crushing model for the system is developed.•Three deformation modes of the system are predicted and investigated.•The criterion to predict the deformation mode of system is established analytically.•A guideline on the design of the self-locked system is provided. The self-locked energy absorbing system can prevent lateral splash of tubes from impact loadings without any requirements for boundary constraints or inter-tube fasteners, thus breaking through the limitation of widely-used round tube systems. To reveal the mechanism of the impact response of self-locked systems, both impact experiment and FEM simulations are carried out. Based on the experimental and simulation results, a one-dimensional theoretical crushing model of the system is developed to analyze the dynamic response of the system, in which a plastic hinge model of the unit cell is proposed for the force-deformation relation. Three deformation modes of the system are predicted and observed, and moreover, the criteria to determine the deformation mode of the system are established analytically. A guideline on the design of the self-locked system is summarized, which is helpful in practical applications. [Display omitted]