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In this study, a wood-based X-type lattice sandwich structure was fabricated by an insertion glue method using medium density fiberboard (MDF) and plywood as panels. Birch was used for the core. The mechanical properties and failure modes of the wood-based X-type lattice sandwich structure were investigated by an out-of-plane compressive test, a short beam shear test, and their matching analytical models. The out-of-plane compressive test and the compression analytical model showed that the failure mode of the plywood and birch combination was mainly shear failure in the core. The cores were broken or had sliding surfaces, while the failure mode of the MDF and birch combination was mainly shear failure of the core at both ends. Although the compression properties of the MDF and birch combination were better, the specific strength and modulus of the plywood and birch combination was larger, which align with the characteristics of lightweight and strong strength. The failure mode of the plywood and birch combination was delamination at both ends of the panel or core breakage, which indicated that this combination had better short beam shear properties. The theoretical models of the compressive /short beam shear properties were in good agreement with experimental results obtained for the plywood and birch combination.

Foam-filled two-dimensional lattice structures were designed, and their compression performance was studied relative to corresponding structures without the foam. The experimental results showed that the compressive load of foam-filled lattice structures improved greatly compared with foam-unfilled specimens. The specific energy absorption (SEA) of foam-unfilled specimens exceeded that of the corresponding foam-filled lattice structure. The maximum energy absorption efficiency of the foam-unfilled lattice structure exceeded 1.5, while that of the foam-filled lattice structure was less than 1. The theoretically predicted compression performance was close to the experimental results. The wood-based lattice structure exhibited excellent specific strength and stiffness compared with other structures.