Analysis of non-conformity concrete: long time effects
Abstract
The paper aims 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 (concrete-filled steel columns) that present 28-day 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.
Keywords: non-conforming; strength gain; structural safety.
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References
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