_Article_  
**Sandwich Panels with Polymeric Foam Cores Exposed to Blast Loading: An Experimental and Numerical Investigation**  
**[PERSON] 1,2,*, [PERSON] 1,2,3**,**  
is reasonably well-known and has been extensively documented, see e.g., [2], while the dynamic compressive behaviour of cellular materials was recently described in [4] and [5]. Sandwich panels used as protective structures traditionally consist of two sheets (or skins) attached to a cellular core. The idea is that the core material will absorb energy during the dynamic event, and as a result, lower the forces transferred to the surrounding structure. The application of the sandwich panel usually governs the choice of skin and core material. As the sheet and core can consist of a range of different materials, there have been numerous studies over the years on various types of sandwich panels depending on the load case. Recently, [PERSON] and [PERSON] [6] investigated the quasi-static behaviour of sandwich panels with steel skins and six different polymeric foam cores, while the same panels were examined under low-velocity impact loading in [7]. The main conclusion from these studies was that in order to minimise the weight and at the same time maximise the energy absorption of the sandwich panel, a low-density foam should be used as core material. It was also found that the energy absorption and the back-skin displacement depended on the velocity range, in addition to the core material and density, so it is not apparent which combination of the different variables that will give the best protection during both quasi-static and dynamic loading. The use of sandwich panels with polymeric foam cores as energy absorbers for blast mitigation has gained increased interest in recent years. Great efforts have been placed especially on the experimental aspects, but [PERSON] and co-workers have presented a series of notable papers on the analytical and finite element modelling of sandwich structures, mainly sandwich beams, subjected to impulsive loading, see e.g., [8; 9; 10; 11]. [PERSON] et al. [12] recently published a book chapter on thick section composite and sandwich structures [13]. Here, their work on blast loaded sandwich panels performed over a ten-year period is summarised. They have studied sandwich structures with various skin and polymer foam core materials, including graded density cores subjected to shock tube and underwater blast loads. Their results show that a graded density core is favourable over a monolithic core, and that the blast load attenuation is dependent on the core gradation layering and arrangement. An increase in load attenuation was found for increasing number of layers and when arranging layers with increasing density [14]. The response of sandwich panels with thermo-plastic polyurethane cores and aluminium face sheets subjected to blast loading was explored both experimentally and numerically by [PERSON] et al. [15]. They observed that the cores could withstand high blast loads, and that the addition of aluminium skins provided additional resistance to impulsive loads. Furthermore, the increase of the core thickness enhanced the performance even more. [PERSON] et al. [16] studied blast loading on structural panels with steel skins and EPS core. They claimed that neither increasing the core density nor the core thickness improved the blast resistance markedly. [PERSON] et al. [17] investigated the behaviour of corrugated sandwich panels filled with a polymeric foam core. It was found that foam filling could enhance the blast resistance of the panel, but the level of improvement strongly depended on the filling strategy. Another type of sacrificial claddings with foam-filled open-top truncated square pyramids was investigated by [PERSON] et al. [18]. They learnt that the crushing resistance increased with foam filling material for quasi-static tests. The conclusions were somewhat more complicated for blast loading, as the foam filling mitigated the response for higher blast loads and had literally no effect for lower blast loads.