Static and Dynamic Strength of Paperboard Containers Subjected to Variations in Climatic Conditions

Abstract

The variability in climatic conditions during product distribution, especially across large distances, can be significant and is well known to affect the mechanical properties of many packaging materials. As the use of environmentally friendly materials, such as paperboard and bio-cushions, increases, the challenge associated with overcoming the effects of extremes in temperature and relative humidity in the distribution chain becomes critical. To date, in the case of paperboard boxes, this is dealt with by accounting for the loss of static (compression) strength with increasing relative humidity. However, no method exists to address the dynamic loads induced by vehicle shocks and vibrations especially for configurations that involve stacked boxes and where the vibration intensity within the stack is influenced by the dynamic characteristic of the boxes themselves. In such scenarios, it is the variation in the stiffness of the box as a function of environmental conditions and dynamic load that needs to be established. This paper describes the evaluation of the fatigue resistance of paperboard boxes subjected to random excitation and compares the results with those obtained from quasi-static compression tests under various environmental conditions. Results reveal a lack of correlation between the static and dynamic tests. This finding is attributed to changes in internal damping of the paperboard box samples which, when reduced, results in increased dynamic force. The paper concludes that static testing alone is insufficient to establish the fatigue resistance of stacked packaging subject to variations in climatic conditions.

Humidity effect in heating and cooling of press‐formed paperboard food packages: Comparison of storing and heating conditions

“…Controlling the moisture content of paperboard requires a desirable humidity condition in storing, manufacturing and usage of the paperboard packages. Variation in relative humidity (RH) can impact mechanical properties of the paperboard packages, with increased moisture content in the paperboard packages previously shown to damage static strength of the packages 1 . The moisture content change in paperboard influences its creep rate, and cyclic humidity conditions aggravate the moisture‐accelerated creep 2 …”

An evaluation of the mechanical performance of extruded wheat starch loose fill

“…It is perhaps even more important to know how these properties vary (as a result of damage to the cushion) when the cushion is subjected to the sustained dynamic loads created by vibrations during distribution. The authors have presented a number of articles on this topic and have shown that Fourier analysis can be used to estimate the system's frequency response function (FRF) from which the sample's stiffness and damping can be extracted. The articles have also shown that variations in the loss of structural health of the cushion can be monitored using the system's short‐time FRF to extract continual relative estimates of cushion stiffness.…”

“…The authors have presented a number of articles on this topic [27][28][29] and have shown that Fourier analysis can be used to estimate the system's frequency response function (FRF) from which the sample's stiffness and damping can be extracted. The articles have also shown that variations in the loss of structural health of the cushion can be monitored using the system's short-time FRF to extract continual relative estimates of cushion stiffness.…”

Fatigue failure and Grms–N curve of corrugated paperboard box

“…Lamb (2011) and Lamb et al (2012) proposed and confirmed that the stiffness can be used to indicate the progression of damage within CPB subjected to sustained random loads. Lamb and Rouillard (2017) also conducted static compression and dynamic random vibration test on CPB and concluded that static test is insufficient for the fatigue resistance evaluation of CPB. The dynamic performance of stacked packaging units has comprehensively been evaluated (Fang and Wang, 2018; Marcondes, 2000; Wang and Fang, 2016).…”