Evaluation of the MD shear test method as a criterion for predicting box compressive strength

• Main Author: Jones, John David
• Other Authors: Marcus, Kashif
• Format: Dissertation
• Language: English
• Published: University of Cape Town 2014
• Subjects: Materials Engineering
• Online Access: http://hdl.handle.net/11427/8620

Includes bibliographical references (leaves 145-149). === Corrugated board is a composite sandwich type material used in the packaging industry worldwide. In the design of corrugated boxes, the stacking strength is an important design parameter. Current research shows that box failure is influenced by the flexural rigidities of the panel and its transverse shear rigidities. McKinlay proposed a new method to measure the MD transverse shear stiffness of corrugated board. This research was aimed at designing a fixture to perform the MD shear test and to evaluate its performance. In addition, the properties that influence box strength were to be investigated. These properties were then to be used in improved box strength predictions. It was found that the designed MD shear fixture was able to measure the transverse shear stiffness of corrugated board in the MD direction with a high degree of accuracy and reproducibility. This method was much easier to perform than the standard block shear test method and also much quicker. This was a very important factor considering the application of this testing method in a research and development environment. In addition, the stiffness test exhibited good possibilities for use as a quality control tool. Extensive testing showed that the material used in the manufacture of corrugated board had a strong influence on board and box strength. In addition, it was found that the separation of the faces in a corrugated board structure had an influence on the strength and stability of the box. Factors such as the manufacturing process and board structure were also found to have an effect on box strength. Box strength predictions were performed using the methods available in the literature. These predictions had good correlation with the experimental box compression values. It was shown that box strength can be accurately predicted from liner and fluting properties and this capability is an important tool in box strength design.