The National Institute of Nuclear Physics (INFN) has evaluated, in collaboration with EnginSoft and University of Salento, the structural behavior of the calorimeter integrated within the Mu2e particles detector, able to provide a set of experimental measurements in order to improve and complete those previously collected inside the tracking detector. The analyzed system is made of a high number of barium fluoride crystals with a particular pattern, placed between two supporting disks; the crystals’ position is established on the basis of a preliminary optimization, aimed at minimizing the empty spaces and at maximizing the system efficiency in terms of quality of collected data. A numerical calculation is realized to assess the mechanical response of the whole system under the gravity effect. The FE model is parametrically built considering central symmetry conditions and the presence of the external wrapping which covers the side faces of each crystals; the geometric pattern has been also used to define the profile of the inner filling areas in-built with disks, to verify the possibility of introducing counter-force systems for the loads re-distribution and to study the process of crystals pilling during the assembly.