This paper concerns the question of how to predict mechanical performance of box and paperboard subjected to fluctuating load/ environmental conditions encountered in end-use. Particularly such performance is notoriously variable (stochastic), and is known to be very difficult to predict.
We have developed a theoretical framework for treating time- dependent, statistical failure based on the recent progresses in statistical physics of disordered materials. The main objective of this study is to experimentally determine the three key parameters that fully characterise the failure of component board subjected to general loading histories, namely the parameter c related to static strength and its uniformity, the load sensitivity/durability parameter W, and the uniformity parameter G of creep lifetime. Results showed that creep lifetime distribution is highly skewed with extreme scatters, but the distribution is still a class of Weibull distribution and can be handled without any problem. The durability parameter W also showed high values comparable with those for fibre-composites. These two results explained very well the variability and load sensitivity of box creep performance observed in the literature.
This proposed approach offers a new set of material property parameters, other than traditional strength, that can be fully exploited in both materials and structural design to enhance end- use performance in the most resource- efficient manner.