A sandwich panel is any structure made of three layers: a low-density core (PIR, mineral wool, XPS), and a thin skin-layer bonded to each side. Sandwich panels are used in applications where a combination of high structural rigidity and low weight is required. The structural functionality of a sandwich panel is similar to the classic I-beam, where two face sheets primarily resist the in-plane and lateral bending loads (similar to flanges of an I- beam), while the core material mainly resists the shear loads (similar to the web of an I-beam).
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