Mechanical behaviour of composite sandwich panels with foamed concrete core reinforced with natural fibre in four-point bending

The four-point bending behaviour of composite sandwich panels made of corrugated steel faces and foamed concrete (FC) cores with a density of 700 kg/m³ is reported. Plain FC (PFC) core and fibre-reinforced FC (FRFC) core, reinforced with an alkaline-treated natural fibre (henequen fibre) at a volume fraction of 1%, were used. FRFC core reinforced with polypropylene fibre was also used as a reference. The results showed that panels with FRFC cores exhibited greater initial failure load, maximum load and energy absorption when compared to the PFC cored panels, which was associated with the enhancements of ductility and toughness of the FRFC cores produced by the fibres. Several energy absorbing mechanisms were observed in the panels, including the development of major tension and shear cracks in the FC core, face wrinkling and face–core debonding. The finite element simulations showed that the face–core bonding plays a crucial role in the structural performance of the panels. The findings presented herein encourage further investigations to assess the use of sandwich panels with natural-fibre reinforced cores for construction applications.