Abstract
A virtually non-destructive method based on the strength of microcores obtained from existing structures was developed forin situ determination of cube strength of concrete types commonly used in the building industry. From a statistical examination of the data derived from compression tests on 480 microcores and 240 cubes a linear correlation law was obtained together with the relative confidence intervals, for both cube and microcore strengths. Then, confidence intervals for future individual observations were worked out so as to be able to assess, to a pre-determined confidence level, estimatedin situ mean strength on the basis of mean microcore strength.
Resume
Afin de déterminerin situ la résistance sur cube de types de béton communément utilisés dans l’industrie du bâtiment, on a mis au point une méthode virtuellement non destructive à partir de la résistance d’éléments carottés dans les ouvrages. On a tiré une loi de corrélation linéaire à partir de l’examen statistique des données obtenues par des essais de compression sur 480 échantillons et 240 cubes, ainsi que les intervalles de confiance à l’usage des futurs utilisateurs de la méthode, qui permettent d’évaluer, à un niveau de confiance prédéterminé, la résistance moyenne estiméein situ à partir de la résistance moyenne des échantillons carottés.
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Indelicato, F. A statistical method for the assessment of concrete strength through microcores. Materials and Structures 26, 261–267 (1993). https://doi.org/10.1007/BF02472947
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DOI: https://doi.org/10.1007/BF02472947