Mechanics of sandwich panels with a buckling-dominated lattice core: The effects of the initial rod curvatures

The mechanical behavior of sandwich panels with a buckling-dominated lattice core (SPBLC) are studied in this work. Based on an analysis of the structural force, deformation, yield point, plastic limit, and bifurcation buckling, the formulas for predicting the structural stiffness and strength are established and then validated by experimental tests and numerical simulations. The negative effects of the initial rod curvatures on the structural stiffness and strength are investigated for SPBLCs with different relative densities, different initial rod curvatures, and different cross-section shapes. Moreover, a comparative study on the energy absorption ability of SPBLCs and traditional sandwich panels with stretching-dominated lattice cores (SPSLCs) is conducted, which shows that a better energy absorption performance can be achieved by rationally designing the initial rod curvature. This work provides a theoretical model and design criteria for sandwich panels with buckling-dominated lattice cores, and it is instructive for the design of other buckling-dominated structures.