Prediction of bending strength of long corrugated boxes

Long corrugated boxes were supported at both ends and bent by a concentrate d force applied at the middle. Boxes with different lengths, cross-sectiona l shapes, flute directions and board strengths were rested, using a standar d compression tester with a fixed platen in accordance with ASTM D-642. An equation was developed to relate compression strength to the various proper ties of the box The correlation coefficient R-2 for the fit to actual data was about 0.4. Boxes having the flutes run around the box had a 20% higher compression strength than with horizontal flutes. The most significant fact or was found to be the board edge crush strength. The results suggest that failure of boxes in bending is due to localized crushing at the point of ap plication of the load, rather than whole-box collapse. Copyright (C) 2001 l ohn Wiley & Sons, Ltd.