Jolanta Pozorska

The comparison of numerical models of a sandwich panel in the context of the core deformations at the supports

The paper presents the problem of static structural behavior of sandwich panels at the supports. The panels have a soft core and correspond to typical structures applied in civil engineering. To analyze the problem, five different 3-D numerical models were created. The results were compared in the context of core compression and stress redistribution. The numerical solutions verify methods of evaluating the capacity of the sandwich panel that are known from the literature.

New insights into classical solutions of the local instability of the sandwich panels problem

The paper concerns the problem of local instability of thin facings of a sandwich panel. The classic analytical solutions are compared and examined. The Airy stress function is applied in the case of the state of plane stress and the state of plane strain. Wrinkling stress values are presented. The differences between the results obtained using the differential equations method and energy method are discussed. The relations between core strain energies are presented.

NUMERICAL ANALYSIS OF SANDWICH PANELS SUBJECTED TO POINT LOADS

The paper concerns the problem of static structura l behavior of sandwich panels. The panels are made of thin steel sheets and a thic k, but soft core. The effects of the impact of concentrated loads on the structural behavior of th e panels are discussed. Several different cases of concentrated loads were considered: load a cting in the plane of the panel, load perpendicular to the panel and the additional action o f c ncentrated bending moment. The loads are transferred to the panel by a small steel slab. The slab is attached to the facing of the panel. Described load cases correspond to situation s e countered in engineering practice. In order to analyze the issue, a 3-D numerical model w as used. Between the facing and the deformable core an interface layer was introduced, wh erein the criterion of damage initiation and damage propagation were defined. Different fail ure modes were taken into account. Due to the character of the problem, the geometrically nonlinear analysis and Riks’ method were applied. For each load case a failure load and extr me stresses leading to failure were determined. The differences in the obtained results w ere explained and the appropriate failure mechanisms were discussed. Analyzed sandwich panel h s fixed geometries, however, made observations are universal. The obtained results te nd to look more carefully at the problem of the impact of concentrated forces. This problem is particularly important in the case of sandwich panels, which due to its construction are very susceptible to local influence. Zbigniew Pozorski, Jolanta Pozorska