The treatment of diverse uncertainties is an important challenge in structural engineering problems, especially from the viewpoint of realistic analysis. Inaccuracy and variability are always present and have to be quantified by either probabilistic, possibilistic, polymorphic or other uncertainty approaches. Regardless to the applied uncertainty quantification method, the numerical predictions have to be useful for structural assessment and decision making. The authors propose in this contribution a benchmark example of a portal frame structure including various uncertainties. The goal of this benchmark study is to compare justifications and decisions provided by probabilistic and non-probabilistic methods with respect to clear challenges of decision making with and without measurements and data assimilation. The engineering problem itself is simple enough to understand and complex enough not to be reduced to a simple formula with uncertain parameters.DFG, 273721697, SPP 1886: Polymorphe Unschärfemodellierungen für den numerischen Entwurf von Strukture