In the engineering structural analysis, one of the most important procedures is the definition of the mathematical model that, under certain hypotheses, appropriately represents the real problem. Then, the model can be evaluated in structural analysis programs, like those based on finite elements, for example.
The Finite Element Method is a numeric procedure and, obviously, the answers are reflexes of the adopted hypotheses. To predict the answer of a physical problem in a satisfactory and reliable way, it is necessary to establish other complex models and to choose, among them, the most appropriate.
In this paper, the applicable hierarchical models to a piping are discussed. The conclusions will be the basis for conception and analysis procedures of a tubular vehicular structure “off-road.”