Local buckling behaviour and design of profiled sandwich panels

Abstract

Fully profiled sandwich panels are commonly used in building structures, but are susceptible to local buckling failures. Current European design standard recommends the use of a modified effective width approach to include such local buckling effects in the design. Recent research has shown that this design method predicts unconservative strengths for panels with slender plates (high b/t ratios). The use of sandwich panels with high b/t ratios is very common in practice due to the increasing use of thinner and high strength steel plates. Therefore, a research project was conducted to investigate the local buckling behaviour of foam supported steel plate elements as used in fully profiled sandwich panels with a large range ofb/t ratios (50 to 500) using experiments and finite element analyses (FEA). Both experimental and FEA results revealed the inadequacy of the current design rule for sandwich panels with slender plate elements. An improved design method was therefore developed based on the large amount of data obtained from validated FEA studies. Finally full-scale tests of fully profiled sandwich panels were undertaken to confirm the accuracy of the new design method. This paper presents an overview of these experimental and finite element analysis studies and design rule development followed by the results of the full-scale tests.