Simulation of axisymmetric discharging in metallic silos. Analysis of the induced pressure distribution and comparison with different standards

The main objective of this paper is to present a new contribution to the problem of dynamic continuum simulation of discharge of cylindrical silos by the Finite Element Method where many attempts have been made in the past by other researchers. We start with a study of the bulk solid constitutive behaviour, the analysis of the stored-solid to silo-wall contact interaction and with a discussion of the remeshing and rezoning algorithms needed to appropriately take into account the large displacements and the associated mesh distortions that appear in this type of problems. Some restrictions of the simulation are due to the axisymmetry of the model and the constitutive assumptions. First of all, a static analysis is accomplished using the usual hypotheses included in different standards to check the ability of the method to reproduce standard available solutions. After this calibration stage, a dynamic analysis is carried out to take into account the effects induced by the silo quaking phenomena, computing the overpressure factor and comparing the obtained results with the pressure estimations established by different standards like the European standard Eurocode ENV 1991-4, the French AFNOR P22 630, the German DIN 1055 or the American ACI 313-97 and R313-97.