The flexural behaviour of composite sandwich beams with a lattice-web reinforced wood core

Abstract

In this study, the flexural behaviour of lattice-web reinforced composite sandwich beams was investigated. The innovative composite sandwich beams consisted of glass fibre reinforced composite materials as the surface layer and web, Paulownia wood and South Pine as the core material. While keeping the external size unchanged, 1, 2, 3, 4 and 5 wood cores were formed by the vacuum infusion process at one time, to develop a different number of lattice-webs. In addition, the wood beam was used as a control. A four-point bending test was carried out on all specimen beams. The equivalent bending stiffness, equivalent shear stiffness, mid-span deflection of the specimens and bearing capacity were analysed. There is a larger plateau stage in the latter part of the load-midspan deflection curve of the beams strengthened by the lattice-web, which means the beams had ductile failure characteristics. Furthermore, the type of wood core greatly influenced the flexural behaviour of the composite sandwich beam, and the optimum lattice-web number of the Paulownia specimen is 2, and that of the South Pine specimen is 3.