Experimental investigation and optimization for after-impact residual strength of a novel gradient corrugated structure

A novel structure based on a gradient corrugated architecture is introduced, and its after-impact residual strength is numerically and experimentally investigated. Low-velocity impact (LVI) and compression after impact (CAI) tests are conducted on designed specimens made of acrylonitrile butadiene styrene (ABS). The experiments reveal that the penetration depth increases linearly with increase in impact energy while the residual strength does not follow the same trend and its degradation rate is decreasing which implies that the structure tends to maintain its strength. A numerical model is developed to simulate the impact and after-impact response of structures with the error range of 2∼15 % for penetration depth values of LVI and less than 5 % error for the residual strength of CAI in comparison with experimental results. In order to maximize the after-impact tolerability, the structural architecture is optimized and realized that trapezoidal cells with decreasing gradient offer the highest specific strength. The sensitivity of the proposed structure to the impact location, with a higher average residual specific resistance, is lower than similar optimized configurations presented in literature. [Display omitted] •Proposing a novel structure based on a gradient corrugated architecture.•Experimental investigation of low-velocity impact (LVI) at different energy levels.•Experimental assessment of compression after impact (CAI) strength.•Developing and evaluating a two-step impact/compression finite element analysis.•Proposing a parametric structure architecture utilizing an optimization process.