Calculation of Box Compression Resistance (BCR) is a challenging task and here the possibility of an engineering approach is considered. The strive has been towards obtaining a simple and generat predictive tool with as few parameters as possible and still obtaining an accurate estimate of the BCR. The model proposed is based on the concept of dividing the package into panels and corner panels. With these remarkably few structural elements it is possible to obtain simple explicit formulas where the only material parameters are given by standard tests in terms of short span compression test and bending resistance. The BCR for different packages is then obtained by a simply summation of the load from the panels and corner panels. A validation agairrst experimental data indicates that, despite its remarkably simplicity, the predictions are very accurate for a wide range of package types, package dimensions, board qualities and loading directions.

Carton board packages are often closed with an adhesive. The adhesive joint thus formed has to meet the demands during the entire product life from converting to end-use. The adhesive joint has to be characterized if it is good or bad for the actual application. Today such characterization is done by manually peeling the joint, immediately after the adhesive application in the gluing machine. The manual peel test is a subjective test that is operator dependent. An operator needs long experience to be able to perform a manual peel test. Therefore, the packaging industry is interested in a test method that can objectively predict good or bad adhesive joints. The adhesive joints have been tested in the so-called Y-peel test arrangement. An advantage of the Y-peel test is that it gives an objective result from the force-elongation curve. Testing has been performed with carton boards of two different thicknesses. Hotmelt adhesive was used and the open time was varied in the glue applicator. It was found that the Y-peel test gives results in qualitative agreement with the manual peel test. Moreover, by evaluating the energy consumption (dissipative energy) during the Y-peel test it was possible to obtain not only a qualitative but also a quantitative assessment of the adhesive joint.

The mechanical behaviour of adhesive joints is critical for the performance of adhesively joined carton board packages. In this work, finite element analyses of hot melt adhesive (HMA) joints in carton board is conducted and compared to experimental results obtained using a Y-peel testing device. The aim of the present study is to analyse the behaviour of adhesive joints tested in the Y-peel testing device using a layered carton board model.The carton board is modelled as a layered structure where the layers are assumed to obey Hill's orthotropic elastic-plastic model, and the interfaces are modelled using a softening orthotropic damage model. The HMA is modelled as isotropic linear elastic, and the influence from a varying elastic modulus of the HMA is explored. It is found that the pre-peak behaviour of the Y-peel force-elongation curves is reasonably well captured by the FE simulations, although the initial stiffness is somewhat too high. Also, the pre-peak behaviour is practically insensitive to changes of the elastic modulus of the HMA.The deformation and delamination pattern obtained in the simulations was compared with microscope pictures taken during the corresponding Y-peel experiments, and it is shown that they conform to the observed behaviour during Y-peel testing at comparable loading levels. However, the delamination opening is somewhat underestimated by the model.

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