Elastic-plastic dynamic response analysis of sandwich beams with lattice truss cores based on minimum principle of acceleration

Based on the minimum principle of acceleration for finite deformation elastic-plastic continuum and with the aid of finite difference method, the dynamic governing equations for the simply supported pyramidal truss core sandwich beams with axial constraints subjected to uniformly distributed impulsive loadings are derived. The effects of shear deformations are reflected in these equations. Through the elastic-plastic numerical calculations and analysis for the simply supported beams, it is found that sandwich beams with pyramidal truss cores have a superior shock resistance in comparison with the monolithic beams of the same mass, and the shock resistance of the sandwich beams is sensitive to the inclination angle of the sandwich core members. The results are useful for the optimal design of sandwich beams with lattice truss cores.