Only two failure modes i.e. face fracture and core shear, experimentally
observed in the bending tests performed in this study, have been
investigated. By assuming that the values of GcLTr and GcTrL of the oil
palm wood core are identical and are equal to one-fourteenth of EcL
[25] of oil palmwood derived in Eq. (8), the failure load for face fracture
(Pf) of both the PR and PP sandwich panels is given by