ERROR EVALUATION ON EXPERIMENTAL STRESS-STRAIN CURVE OBTAINED FROM TUBE BULGING TEST

The paper is focused on a sensitivity analysis developed to study the relevance of experimental hardening curves obtained from tube bulging test to quantify the influence and the contribution of experimental uncertainties on the response variability. The experiments are based on "online" measurements of the internal pressure and the bulge height. A semi analytical model developed from a geometrical representation of the bulged tube and equilibrium of infinitesimal volumes (slab method) permits to evaluate the stress-strain curve. The differentiation of all the equations of the model and the evaluation of all the input parameters allow to get the total uncertainty on the resulting hardening curve and to identify the critical experimental parameters. Hence the results of this sensitivity analysis open up ways of improvements for conducting experimental tube bulging test.