Abstract:
A plastic-hinge finite element formulation is presented for the elasto-plastic analysis of I-beams curved in plan. The formulation is based on the assumption that the plastic behaviour is lumped at the ends of the beams. The behaviour of the plastic hinges is characterised by an interaction relation developed specifically for I-beams curved in plan. The interaction equations incorporate the significant effects of the included angle. The associative plasticity approach is adopted; thus the normality condition in conjunction with the yield surface at the stress resultant level is used. The results obtained from the developed plastic-hinge method are compared with a more sophisticated finite element model which is based on the plastic-zone analysis that considers the gradual yielding of the cross-section as well as yielding along the beam. The elastic predictorradial corrector algorithm is adopted for this. The results show that the formulation provides conservative results for the elasto-plastic analysis of I-beams curved in plan subject to vertical loading.
