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Calculate a fatigue damage field experienced by a structure; a critical plane in which shear is maximum; or a maximum allowable vibration amplitude.

Calculation of a damage field: from a history of equivalent stresses (signed von Mises stresses) or equivalent deformations (signed second-order invariant) calculated at nodes or at Gauss points, we calculate a magnitude field that contains the damage suffered by the structure at each node or at each Gauss point. The elementary loading cycles are extracted by a cycle counting method (method RAINFLOW); the total damage suffered by the structure is the sum of the damage associated with the elementary cycles.

Priming criterion: to calculate damage, it is essential to have a priming criterion. The priming criteria are provided by the keyword (as Dang-Van criterion…). It is also possible for the user to build a criterion using the formula of pre-defined quantities.

Critical plane and maximum shear: from a history of stresses calculated at Gauss points or at nodes, in the case where the loading is periodic, we calculate a magnitude field that contains, among others: the half-amplitude of maximum shear, the associated normal vector, the associated normal vector, the number of cycles at break and the damage corresponding to the Gauss points or to the nodes. If the load is non-periodic, the quantity field contains the maximum damage and the normal vector associated with the Gauss points or the nodes.

Maximum permissible vibration amplitude: this option aims to estimate the maximum allowable vibration amplitude of a structure subjected to static loading (known) and dynamic loading (unknown). From the static stress and the modal constraints of the natural modes considered, calculated at Gauss points or at the nodes, the maximum vibration amplitude is calculated using a uniaxial fatigue criterion.

Produce a cham_elem or cham_no concept.