Analysis of non-conformity concrete: long time effects

ABSTRACT The aims of this paper is to contribute to the analysis of non-conformity concrete, focusing on long time effects. A review of compressive strength evolution, results variability and acceptance criteria was made. In addition, it is presented a case study of a nonconforming concrete used in composite structures (concretefilled steel columns) that present 28 days strength below the specified. Considering long time effects, a nominal strength gain above the limits considered in technical standards was observed. This analysis, associated with a revision of the structural design and a carefully assessment, could help decision taking in case of non-conformity concretes.