The design of infrastructure that is protective against ballistic and blast fragment impact requires a series of tests which are costly. In this study, the authors propose a methodology based on a practical approach with the aim of facilitating the attainment of parameters of a constitutive model representative of the behavior of the main structural materials used in common constructions, namely clay or concrete, with the objective of being able to make hypotheses that are considered convenient, at a moderate cost. To this end, the proposed methodology interpolates the parameters of the target material using ballistics tests framed according to the values of related materials and compared with those existing in the literature.