Influence of Moisture of Light-Weight Concrete Containing Lightweight Expanded Clay Aggregate on Test Results Obtained by Means of Impact Hammer

Abstract:

Properties of light-weight concrete congaing lightweight expanded clay aggregate differ from the ones of normal-weight concrete containing natural normal-weight aggregate. Particularly, when compared with natural normal-weight aggregate, these differences are due to lightweight aggregate being characterized by significantly lower strength and bulk weight as well as higher absorptivity. Properties of expanded clay lightweight aggregate influence the ones of light-weight concrete, too. Parameters obtained by means of Schmidt impact hammer non-destructive testing are influenced by series of factors, among others also concrete moisture. Moisture of light-weight concrete containing lightweight aggregate influences rebound number of Schmidt impact hammer. As to Schmidt impact hammer type N (2.25 Nm impact energy), rebound number on dry concrete exceeds the one on waterlogged concrete by 21 %. Correction coefficients for rebound number correction were defined taking into account moisture of light-weight concrete under testing.

• Periodical: Advanced Materials Research (Volumes 753-755)
• Pages: 663-667
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.753-755.663
• Online since: August 2013
• Authors: Jiří Brožovský
• Keywords: Impact Hammer, Light-Weight Concrete, Moisture, Rebound Number

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