Refined nonlinear finite element models for corrugated fiberboards

A refined nonlinear finite element modeling approach is presented for the analysis of corrugated fiberboard material and structural systems. The anisotropic and nonlinear material stress-strain behavior of the linerboards and fluting medium layers of the corrugated fiberboard composite system is modeled using orthotropic material model with Hill's anisotropic plasticity. Uniaxial tensile tests are conducted separately for the linear and medium fiberboards to generate their stress-strain curves in the cross and machine directions (CD and MD) orientations that can be used to calibrate the anisotropic plasticity model for each of the corrugated board layers. The combined material and structural modeling approach includes both material and geometric nonlinear effects. Once the material nonlinear behavior has been calibrated, we simulate the response of several corrugated material systems subjected to Tappi-type edge crush test (ECT) using a clamping fixture. An alternative non-standard ECT geometry having larger free span length is also examined. Simulations are also performed for multi-wall corrugated systems during ECT. Failure in the FE models is monitored using the Tsai-Wu anisotropic failure criterion calibrated from the uniaxial tests of the layers. Refined parametric models that explicitly incorporate glue-line characteristics are also generated in order to examine their effect on the overall response. The proposed refined modeling approach yields good predictions for the overall mechanical behavior and the ultimate failure for a wide range corrugated systems. (C) 2008 Elsevier Ltd. All rights reserved.