A spot weld finite element for structural modelling

A new finite element assembly, to account for the structural behaviour of t he region surrounding a spot weld, is developed. The formulation derives fr om the analytic solution of two circular sheets externally clamped, with a central rigid core connecting them (representing the spot weld). The effect ive modelling strategy of the above mentioned region makes use of equivalen t beam elements; therefore, the implementation is possible in any structura l code. The aim is to use this assembled element for the region around the spot: two assembled elements, connected by a link, form the spot weld conne ction between two metal sheets. The analytic solution is provided for any p ossible typology of loading acting on a spot weld (shear, bending and ortho gonal loads). Moreover, the link connecting the two sub elements may be con sidered rigid as well as deformable, this can be very useful to evaluate fa tigue damage evolution in structures jointed with many spot welds. Using these assembled elements for the spot weld region, an important incre ase in the accuracy is reached, as demonstrated in the example. However. th e accuracy does not imply an increase in the total number of degrees of fre edom of the whole model. (C) 2000 Elsevier Science Ltd. All rights reserved .