Stiffened Sandwich Beam Using Glass Fiber Reinforced Inorganic Phosphate Cement (IPC)

This paper deals with ordinary and stiffened sandwich beam using fiber reinforced Inorganic Phosphate Cement (IPC) with a polyurethane foam core. Novel IPC stiffeners are proposed and their performance to achieve composite stiffness of sandwich structures is investigated. Experimental and analytical methods are presented assuming that the specific response of beams in bending can be assimilated to elastic behaviour. This analysis method based on analysing a sandwich beam would be to treat it as I-beam. Three different structures of Sandwich beams with Inorganic Phosphate Cement (IPC) matrix composite faces and stiffeners were prepared for the experimental work; an ordinary sandwich structure (OSB), reinforced core sandwich (RCS), and integral blade sandwich (IBS). A good correlation was found with the theoretical analysis. The results confirm that the IPC-stiffeners improve the deflection resistance, and strength of the structures. In this study, the overall stiffness of the 85 cm span sandwich beams increased by factor of 7.6. Although the IBS structure expressed similar deflection behavior to RCS verse applied load, the experimental results show that this structure loses its integrity under lower applied load compared with RCS.