2.1 Sandwich structures
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2.1.4 Failure modes
Sandwich panels are characterized by a multitude of failure modes, many of which being
unique to sandwich structures. Identifying the different failure modes and damage
mechanisms is crucial when analyzing sandwich structures. In the following the most important failure modes are illustrated and briefly described. This overview is derived from
standard literature [Bit97], [Zen97], [Hex00].
Table 2 Failure modes in sandwich structures
Local indentation
Initiated by low compressive strength
of the core
One of the most critical damages due
to initiation of face debonding
Core shear failure
Due to low shear strength of the core
Common damage in bending and due
to local loads around core reinforcements
Face yield/fracture
Resulting from tension, compression
or shear, due to insufficient face
sheet strength
Global buckling
Due to insufficient panel thickness or
core shear modulus
Face dimpling (intracell buckling)
Due to large core cells and thin face
sheets.
May propagate to surrounding cells