Analysis and testing of corrugated board panels into the post-buckling regime (original) (raw)

BASIC TESTING AND STRENGTH DESIGN OF CORRUGATED BOARD AND CONTAINERS Doctoral Thesis by

2015

Detta är en tom sida! Packaging serves a lot of purposes, and would be hard to do without. Packaging protects the goods during transport, saves costs, informs about the product, and extends its durability. A transport package is required to be strong and lightweight in order to be cost effective. Furthermore, it should be recycled because of environmental and economical concerns. Corrugated board has all of these features. This thesis is compiled of seven papers that theoretically and experimentally treat the structural properties and behaviour of corrugated board and containers during buckling and collapse. The aim was to create a practical tool for strength analysis of boxes that can be used by corrugated board box designers. This tool is based on finite element analysis. The first studies concerned testing and analysis of corrugated board in three-point-bending and evaluation of the bending stiffness and the transverse shear stiffness. The transverse shear stiffness was also meas...

Parametric study of the post-buckling strength of structural core sandwich panels

Post-buckling strength of simply supported orthotropic corrugated board panels subjected to edge compressive loading has been investigated using geometrically non-linear finite element analysis (FEA). Adjustments of the transverse shear stiffnesses in the FEA were necessary and performed by comparing the critical buckling load calculated by FEA with a closed form solution. The collapse load of the sandwich plate was calculated based on material failure of the facings predicted from Tsai-Wu failure theory. Parametric studies were performed to investigate the sensitivity of the collapse load to changes in the transverse shear stiffnesses of the core, initial out-of-plane imperfections, asymmetry in board construction, slenderness ratio and eccentric loading of the plate. It was found that a reduction of the transverse shear stiffnesses of the core below a certain limit produces a significant reduction in the collapse load. Panels are said to be insensitive to imperfections and this holds true when the imperfections are the same as or lesser than the thickness of the panel, but a 40% reduction of the collapse load is observed for imperfections that are ten times the panel thickness. From a design point of view it is shown that a symmetrical board is preferred because an asymmetric board as well as eccentric loading of the panel significantly reduce the collapse load. It is also shown that the critical buckling load is directly related to the slenderness ratio of the panel whereas the collapse load is not.