Composite sandwich structures enable the development of lightweight and stiff chassis for Formula Student race cars; however, their design is more demanding than that of conventional tubular chassis due to the complexity of multilayer structural analysis. The aim of this thesis was to develop a software tool for estimating the stiffness and failure load of sandwich structures under three-point bending and comparing the predictions with experimental measurements.
The calculator is based on classical laminate theory to determine the stiffness and stress state of the skins and on an elastic foundation beam model to describe local deformation and core crushing. It includes four failure criteria, a laminate database, and automatic comparison of theoretical predictions with experimental results. Representative sandwich specimens were manufactured and tested under three-point bending.
The results showed that the model predicts structural stiffness with relatively good accuracy, while consistently underestimating the failure load with small deviations. Test-rig compliance has a negligible influence on the deviations. The calculator is suitable for preliminary structural assessment but cannot replace experimental validation.
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