On the prediction of elastic-plastic generalized load-displacement responses for tubular joints

An energy-based method is presented for the prediction of the elastic-plastic force-displacement and/or moment-rotation responses of tubular joints for arbitrary radial loading paths under the action of up to four combined forces and moments. The method is based on the results of a sample of load paths obtained from computational models or measured from experimental tests. The work is important in the context of the elastic-plastic behaviour of structures in general and in particular as a basis for the development of single elastic-plastic tubular joint elements. The method employs normality of the generalized displacement vector to level hypersurfaces of total (elastic-plastic) complementary work.