Stiffness and strength of oil palm wood core sandwich panel under center point bending

• Modulus and strength of oil palm wood exhibit a power-law increase with density.
• Higher density of oil palm core increases stiffness and strength of sandwich beam.
• Direction of oil palm core has little effects on stiffness and strength of sandwich beam.
• Failure changes from face fracture to core shear with lowering of core density.
• Derived model can predict stiffness, strength and failure mode of sandwich beam.

This paper presents a study of the bending's stiffness and strength of oil palm wood (OPW) core sandwich panel overlaid with rubberwood veneer under center point bending. Parameters including density and grain orientation of OPW core, rubberwood veneer thickness and span length were investigated. An experimental evaluation of some mechanical properties of OPW and the bending stiffness and strength of the sandwich beams was performed. Linear elastic beam theory was used to predict the bending performance of the panels. Results show that the linear elastic beam theory with the uses of the power law expressions of Young's moduli and shear strength of the OPW as a function of density derived within this study, adequately predicted the stiffness and bending strength of the sandwich beams. Higher OPW core density increased stiffness and strength of the beam. Failures by face fracture and core shear were observed which the latter tended to occur at low OPW core density, relatively thick veneer face and short span length. Grain orientation of OPW core little influenced stiffness and strength of the sandwich board. Finally, the stiffness and failure load equations of the OPW sandwich board were proposed for practical uses of this product.