Sensitivity analysis of uncertainties to geometry and material properties in finite element models

Finite element (FE) method is widely used to analyse the structural behaviour of the most mechanical systems. These are affected by a natural variability of geometric parameters and material properties, especially dealing with biomechanical system. Therefore, input variables should be defined not by a single value but trough a suitable statistical distribution. Although several authors agreed on the resulting of these uncertainties on the FE model prediction, to date only few probabilistic studies has been performed. In this paper, a sensitivity analysis was carried out on an FE model of a bone cement specimen subjected to a static tensile test analysing the influence that geometric and material properties uncertainties have onto the maximum tensile stress pointed out in three region of interest. Results were compared with the analytical exact solution of the problem from the simple beam theory. The aim of the present work was to validate a statistical procedure of incorporating potential sources of errors into a finite element analysis and to quantify their influence on the accuracy of the output parameters.