Abstract: Environment humidity and geometrical parameter have the important effect on the mechanical characteristics of honeycomb paperboards. The impact compression of honeycomb paperboards is investigated by using the experiment and finite element method, and the impact load carrying capacity and energy absorption ability are obtained for honeycomb paperboards with different thickness-to-length ratios under different humidity. The elastic modulus and yield strengths of the corrugated medium and double honeycomb cell wall are exponentially decreased with the increasing of the relative humidity, and the elastic modulus and yield strength of the double honeycomb cell wall are obviously large than those of the corrugated medium. The deformation of paper honeycombs under the dynamic impact is similar to that of metal honeycombs and exhibits strong localization, that is, the loading end of the paper honeycomb is crushed at first, then the deformation band grows and spreads to the rest of the specimen and the paper honeycomb cell walls fold progressively. The initial peak stress, plateau stress and energy absorption of honeycomb paperboards are decreased remarkably with the increasing of the relative humidity and the decreasing of the thickness-to-length ratio. The energy absorption curves obtained for honeycomb paperboards with different thickness-to-length ratios under different humidity are very valuable to the design of cushion packaging of products.

Key words: Energy absorption, Finite element method, Honeycomb structures, Impact testing, Paperboards, Relative humidity