Uncertainty Analysis, Verification and Validation of a Stress Concentration in a Cantilever Beam

S. Kargar, and D. Bardot
University of Alabama, Huntsville, AL, USA
Published in 2010

In this paper we compare the results from a bending cantilever beam experiment with the theoretical values and COMSOL finite element simulation results. In the experiment a simple cantilever beam with a hole is loaded at the end. Measurements are recorded by four strain gauges mounted on the beam, three near the hole and one at a location where the nominal stress is equivalent to that of a similar beam without a hole. This geometric discontinuity causes a stress concentration around the hole and this stress concentration is reported with estimates of the experimental uncertainty. To determine the optimum mesh size for the simulation, a grid convergence study was conducted by monitoring the predicted maximum deflection at the end of the beam and comparing it to the theoretical value. Monte Carlo simulations were used to quantify the uncertainties associated with the simulation inputs such as the measured beam dimensions and modulus of elasticity. This paper presents an end-to-end example of uncertainty quantification, model verification and validation.