Shear Modulus Determination of Cuboid Metallic Open-Lattice Cellular Structures by Analytical, Numerical and Homogenisation Methods

The shear response of irregular open-lattice cellular cores made of interconnected metallic struts is analysed, and the core shear modulus in the three material principal directions is derived. The analytical approach is based on the technical beam theory, which is used for the determination of the unit-cell response under complex loading. The influence of the strut geometrical parameters and unit-cell shape and size on the cellular core shear stiffness is determined. The analytical determination of the unit-cell properties is successfully validated by a reference numerical model of the unit cell, which is developed for comparison purposes. Furthermore, the homogenisation principles are applied to the prediction of the shear response of a core block structure comprising a high number of unit cells, for which experimental results were available; the comparison revealed that the experimental results coincide well with the results obtained from the homogenised model.