Test fixture for eccentricity and stiffness of corrugated board

Abstract

Of particular importance for the mechanical response and load-bearing capacity of corrugated board boxes is the manner in which load is introduced in the vertical panels through the horizontal flaps and the adjoining creases (folding lines). This study reports on a test fixture developed to measure the effective eccentricity moment acting on the vertical panels of corrugated board boxes. The axial compressive response of the creased board can also be measured using the new test fixture. The deformation mechanism of the board was monitored by visual inspection and photographically recorded and related to the measured eccentricity moment. The results show that significant eccentricity of the load path exists, which depends on the degree of lateral constraint and amount of axial deformation in a quite complex manner. The axial compressive response was found to be independent of the degree of lateral constraint and unsupported length of the specimen, which is evidence for the majority of the axial deformation occurring in the creased region. Photographic recording of the deformation mechanism of the creased region during compressive loading verified that the board is loaded unevenly as evidenced by kink zone formations appearing at opposite sides at different axial deformation levels.