Investigation of the Environmental Effect of Unit Load Design Optimization Using Physical Interaction Between Pallets and Corrugated Boxes

Packaging sustainability has become one of the most notable issues of this era. Many researchers have endeavored to characterize or compare the environmental burdens of a single level of packaging, such as primary, secondary, or tertiary packaging. However, goods are often handled, stored, and transported through the supply chain system in unit load form consisting of pallets, corrugated boxes, and load stabilizers. Hence, it is important to holistically understand the environmental impact of not only individual packaging levels, but also the unit load form. We can use the interactions between the unit load components to reduce the environmental burdens generated in the supply chain system. Past studies discovered that pallet top deck thickness has a huge effect on corrugated box compression strength. Using this knowledge, researchers were able to optimize the cost of unit loads by increasing pallet top deck thickness and reducing the board grade of corrugated boxes. This study (1) further discovered how different unit load design factors, such as initial top deck thickness, pallet wood species, box size, and board grade, affect the performance of the previously proposed unit load design optimization method, and (2) we investigated if the unit load optimization method could also enhance unit load sustainability. The study's first phase identified that the benefits of increasing top deck thickness were more pronounced as the initial top deck thickness decreased, higher board grade boxes were initially utilized, and smaller-sized boxes were used. The second phase of this study showed that increasing top deck thickness and reducing the board grade of corrugated boxes could offset environmental impacts by as much as 23%. Environmental benefits were mostly achieved by reducing the amount of relatively more-processed materials in the corrugated boards. This phase also provided preliminary unit load conditions as guidance for unit load professionals to estimate the possibility of optimizing their unit load design in an environmentally beneficial way.