evaluation of the static behavior of wpc-gfrp sandwich panels: an experimental, theoretical, and numerical study

Wood-plastic composite (wpc) is a material composed of wood particles, recycled plastics, and resin, and plays an important role from an economic standpoint. due to its high compressive and tensile strength, wpc can be used as decking in applications such as pier flooring or small bridge decks. in this study, different glass fiber-reinforced polymer (gfrp) layers were employed to investigate the ultimate load, stiffness, and maximum deformation of wpc-gfrp sandwich panels. given wpc's lower tensile strength relative to its compressive strength, the reinforcing layers were primarily applied to the bottom face sheets. the loading applied in these experiments was of two types, linear and point loading, perpendicular to the panel surface, to simulate the conditions when such panels are used as flooring. following the experimental program, theoretical and numerical methods were employed for further analysis of the specimens. in the theoretical approach, beam theory was used because the loading, support conditions, and material behavior closely resembled those of beams. in the numerical approach, uniaxial tests were conducted to determine the material properties and stress–strain relationships, which were then implemented in the finite element model. overall, the results indicate that the use of a single gfrp layer significantly improves both the strength and stiffness of the panels. however, adding multiple layers does not lead to a considerable improvement in strength, although it slightly enhances stiffness. from an economic perspective, the use of more than one gfrp layer does not appear to be cost-effective. furthermore, a good agreement was observed among the experimental, theoretical, and numerical results, confirming the reliability of the modeling approaches.