Bending performance of post-fire lightweight polyethylene metal sandwich panels

This paper investigated the bending performance of post-fire lightweight polyethylene metal sandwich panels with different aspect ratios and span conditions using actual fires and post-fire three-point bending tests. The damage patterns and buckling behavior of sandwich panels after an actual fire are discussed. The effects of lamination with dimensional ratios (vertically and horizontally laminated) and span (single and double-span) on parameters, such as fire spread behavior, buckling behavior, load-deflection, bending modulus degradation efficiency, and residual bending stiffness were investigated. The results showed that the double-span fixation mode formed a double-peaked flame, becoming more evident as the aspect ratio decreased. The double-span helped suppress the upward propagation of the flame and reduced the degradation of the bending modulus. The bending stiffness was 10-20% higher than that of the single-span sandwich panels. In addition, the maximum service limit deflection of post-fire sandwich panels with different spans was also derived based on the normal limit of use standard.