FEM simulation of simply supported GLARE plates under lateral indentation loading and unloading

• The permanent dent depth of GLARE plates increases for increasing indentation.
• The unloading curves of a GLARE plate under indention are approximately parallel.
• A graphical method to obtain unloading curves of GLARE plates is proposed.
• As the MVF of a GLARE plate decreases, the unloading path decreases more abruptly.
• For equal indentation when plate radius increases, permanent dent depth decreases.

In this article, a 3-D finite element modeling procedure is implemented, in order to predict the static loading and unloading response of thin circular simply supported GLARE plates, subjected to lateral indentation by a hemispherical indentor. ANSYS software is used and a non-linear analysis is employed with geometric and material non-linearities. The modeling procedure is applied to GLARE 2-2/1-0.3 and GLARE 3-3/2-0.3 simply supported plates with 40 mm radius, and to a GLARE 2-2/1-0.3 simply supported plate with 50 mm radius. The load–deflection curve during loading and unloading, and the permanent plate deflections of the GLARE plates are calculated for different maximum loading indentation levels. It is found that the permanent dent depth of the GLARE plates is increased as the maximum loading indentation increases. It is revealed that for the same maximum loading indentation, when the GLARE plate radius is increased, the permanent dent depth is reduced. It is also found that the unloading load–deflection curves, corresponding to different maximum loading indentation levels of each GLARE plate, are approximately parallel. Based on this finding, an approximate graphical method to obtain unloading curves is proposed. The role of the metal volume fraction to the loading–unloading response of the fiber–metal laminates is also investigated.