A FEA model, representing a structure, contains at least many finite elements for metal portion, a set of metal necking failure criteria (critical and fracture strain values defined in form of a loading path diagram) and the neck's characteristics (neck's width and a profile of strain values within the width) are received in a computer system. At each solution cycle of a time-marching simulation using the FEA model, following operations are performed at each integration point of every finite element: identifying major and minor strain values and corresponding directions from the computed strain values, calculating an equivalent metal necking failure strain value (εe) in the major strain direction with a formula based on corresponding critical and fracture strain values, the neck's characteristics and a characteristic dimension with respect to the major strain direction, and determining metal necking failure, which occurs when the major strain value is greater than εe.