Energy absorption properties of multi-layered corrugated paperboard in various ambient humidities

This paper develops a mathematical model to depict the energy absorption properties of multi-layered corrugated paperboard (MLCP) in various ambient humidities. It is a piecewise function to model the energy absorptions corresponding to three deformation stages of MLCP (elastic stage, plateau stage and densification stage) separately. Simple formulas are derived for each stage which relating the energy absorption capacity of MLCP to the thickness-to-flute pitch ratio (image) of corrugated-core cell, the mechanical properties of corrugated medium tested under a controlled atmosphere [23 °C and 50% relative humidity (RH)], and the RH. The theoretical energy absorption curves are then compared with experimental ones and good agreements are achieved for MLCP with wide range ratios of image in various ambient humidities. Results of this research can be applied in the optimum design and material selection of cushioning packaging with multi-layered corrugated paperboard.