Image analysis for determination of cement content in concrete to improve accuracy of chloride analyses

The chloride content C sub cl expressed as %Cl by weight of cement is important in condition assessment of reinforced concrete structures. Whereas standardized procedures determine C sub cl in concrete powder, the cement content C sub m is generally assumed equal to the mix design or an experience-based constant value. This work shows in concrete with maximal aggregate diameter 32 mm, C sub m exhibits significant variability in 50 mm diameter cores, because the specimens are too small to be representative of bulk concrete. In such specimens, C sub m might differ from the bulk cement content by a factor of up to 2. Thus, a reliable determination of C sub cl in terms of %Cl by weight of cement requires the analysis of both C sub cl and C sub m in a concrete specimen. A procedure based on colouring the cement paste, scanning the specimen surface, and image analysis allows the practically non-destructive determination of C sub m with good accuracy.

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  • English

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  • Accession Number: 01638168
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Jun 2 2017 9:54AM