Sensitivity analysis of a drying model concerning concrete delayed strains in containment vessels by means of a non-intrusive method

Drying impacts the delayed behavior of the containment vessels. Many tests of loss of mass are available in the data base of Electricité de France or in the literature and make it possible to evaluate profiles of water content in a test tube. The macroscopic retiming of the drying parameters and the uncertainty level on the latter force to carry out a sensitivity analysis over the lifespan of the vessel. The ranking of the input parameters (sensitivity analysis) was carried out using an expansion of the model response onto the polynomial chaos basis (non intrusive regression method) and computing the Sobol' indices analyticaly from the polynomial chaos coefficients. One is more particularly interested in the delayed vertical and tangential strains. Initially, the parameters of Mensi's law and the water contents actually play the most important role. Then, the parameters of the desorption curve desorption and more particulary the initial water content are the most important parameters.