The field of proof-loading has expanded over the last decade with excellent examples of successful collaborations and multidisciplinary approaches. Advanced testing has, as one of the essential subjects in an interdisciplinary assessment, brought significant value to further understanding of structural responses and failure mechanisms related to concrete bridges. This paper presents laboratory and field collapse testing examples in the Netherlands and Denmark, and related investigations of the response of non-shear reinforced slabs until failure. A special focus is dedicated to load application, examples of test approaches, some practical insights and test result comparison. Considerations of the laboratory and field test planning in synergy will be discussed based on the results and experiences obtained. A substantial margin to ultimate failure was found from crack identification or other measurable warnings in all tests. These observations suggests that it is possible to get sufficient warning even for non-shear reinforced concrete slabs structures.

Safe proof loading of concrete bridges requires reliable stop criteria. Such criteria must ensure sufficient margin to the ultimate resistance and may be based on observations from advanced testing. In particular, the identification of thresholds related to pre-stressed and non-shearreinforced slab structures is currently ongoing with an addition of specific focus on potentially brittle failure modes of such structures. This paper presents representative examples of identifying stop criteria and target load thresholds using a combination of laboratory- and in-situ testing. Responses from recently tested structures and structural elements will be presented to enable discussion and perspectivation. The presented test results show measurable warning with sufficient margin from crack initiation to stop criterion. It was additionally seen that the target load often may be the governing threshold when proof load testing.