Numerical Modeling and Experimental Investigation of the Failure Modes of the Cellular Foam Sandwich Structures

Abstract

The use of sandwich materials can lead to economical advantages in many applications by means of weight reduction. In spite of its large demand , its distribution in the field of mechanical engineering is constrained due to unsolved problems in the connection technology and uncertainties in the mechanics of such structures. Hence, in this field, there exists a demand for the support of engineers who facilitate the design of sandwich structures. This paper describes the methods utilizing strategies for 3D-modeling and the simulation of plating by using the commercial FEM -System ALGOR, which interface with the CAD-system. The four-point bending test was performed in order to determine the load-deflection behavior of a sandwich plate under static loading conditions. In the experimental part of the work, the simulated loading case was tested repetitively on the servo-hydraulic machine. The linear elastic behavior and the different failure of sandwich plate conditions were investigated as to the testing environment. The results obtained with the association of the FEM criteria, were compared to the analytical and experimental results. The analytical data reflects that the computed compressive stress values facilitate a good working agreement with the analytical result s. The value of the shear stresses from the simulation was approximately 0.26 MPa, while according to the empirical formulas by Zenkert, the shear stress was amounts has to calculated to be 0.29 MPa. The results showed, that the core shear failure took place in the same regions, which were a good agreement between the FEM and experimental data.