The goal of model-based structural identification is to find suitable values of parameters that affect
structure behaviour. To this end, measurements are often compared with predictions of finiteelement
models. Although residual minimization (RM) is a prominent methodology for structural
identification, it provides wrong parameter identification when flawed model classes are adopted.
Error-domain model falsification (EDMF) is an alternative methodology that helps identify candidate
models – models that are compatible with behaviour measurements – among an initial model
population. This study focuses on the comparison between RM and EDMF for the structural
identification of a steel bridge in Exeter (UK). Advantages and limitations of both methodologies are
discussed with reference to parameter identification and prognosis tasks such as quantification of
reserve capacity. Results show that the employment of RM may lead to wrong identification and
unsafe estimations of reserve capacity.