Bending behavior of pyramid lattice sandwich beams with non-uniform truss cores

To improve the three-point bending capacity of the pyramid lattice sandwich beam, a non-uniform pyramid lattice sandwich structure is proposed in this paper by assigning different diameters to the tensile and compressive core rods and setting the ratio of the diameters of the two kinds of core rods as a non-uniform coefficient. The influence of the non-uniform coefficients on the three-point bending performance of the pyramid lattice sandwich beam is analyzed theoretically and numerically. Results show that the introduction of the non-uniform coefficients can significantly improve the bending ultimate bearing capacity of the structure. Compared with the uniform lattice sandwich beam, the optimal non-uniform coefficients increase the bending ultimate bearing capacity by 39%. Moreover, it is revealed that the optimal non-uniform coefficient ([Formula: see text]) decreases with the increase of the total mass of the structure. The research on the three-point bending performance of non-uniform lattice sandwich beams in this paper can provide guidance for the optimal design of lightweight lattice sandwich structures.