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This article presents an approach for assessing the damage resistance of H30 rigid foam subjected to local static loading. The main goal of the experimental part of this paper is to obtain the loaddisplacement response of foam beam specimens under static indentation by steel cylindrical indentors for both loading (indentation) and unloading stages. The instant residual dent magnitude is also measured in the testing. The nonlinear character of the mechanical behavior and the formation of a residual dent (after unloading) are attributed to local crushing of the foam in the zone directly under the indentation area. A visual inspection of a lateral surface of the foam specimens after indentation tests revealed that the local damage underneath the indentor consists of crushed and highly compacted foam, while the rest of the specimen is almost undeformed. A two‐dimensional numerical model is developed to simulate the static indentation response using the ABAQUS computer code. No overall bending of the foam specimens is assumed. The finite element modeling procedure takes into account both physical and geometrical non‐linearities. In order to simulate the plastic part of the response, the model employs the *CRUSHABLE FOAM and *CRUSHABLE FOAM HARDENING options. The modeling procedure is capable of analyzing indentation as well as unloading of foam beam specimens. Thus, the instant residual dent can be predicted. Results generated by this model exhibit good correlation with indentation tests data, thus substantiating its validity.

The purpose of this paper is to study theoretically the ability of the prestressed foam core composite sandwich Split Cantilever Beam (SCB) for generating mixed-mode II/III crack loading conditions (the mode II fracture was provided by prestressing the beam using imposed transverse displacements).

The concepts of linear-elastic fracture mechanics were used. The fracture behavior was studied in terms of the strain energy release rate. For this purpose, a three-dimensional finite element model of the prestressed sandwich SCB was developed. The virtual crack closure technique was applied in order to analyze the strain energy release rate mode components distribution along the crack front.

It was found that the distribution is non-symmetric. The analysis revealed that a wide mixed-mode II/III ratios range can be generated by varying the magnitude of the imposed transverse displacement. The influence of the sandwich core material on the mixed-mode II/III fracture behavior was investigated. For this purpose, three sandwich beam configurations with different rigid cellular foam core were simulated. It was found that the strain energy release rate decreases when the foam core density increases.

For the first time, a mixed-mode II/III fracture study of foam core composite sandwich beam is performed.