A platform for research: civil engineering, architecture and urbanism
A platform for research: civil engineering, architecture and urbanism
Scaling resistance of high performance concretes containing a small portion of pre-wetted lightweight fine aggregate
AbstractThe subject of the investigation was the influence of pre-wetted lightweight aggregate on damage of the concrete surface due to cyclic freezing and thawing in the presence of de-icing salts tested according to the Swedish Standard SS 13 72 44 (the Borås method). Six series of concrete specimens were made with the same water/binder (w/b) ratio 0.32, cement volume 400kg/m3 and content of superplasticiser 8.8kg/m3. One series, S3/2, contained an air-entraining agent. Series S4/7 and S4/8 were made with water/cement ratio equal to 0.45 and a lower cement content 340kg/m3. In a few series the sand fraction 0–2mm and basalt fraction 2–4mm were partly or totally replaced by wetted lightweight aggregate. Concretes S3/1, S3/3, S4/7 and S4/8, failed the test. The best results were obtained for concrete S3/6 (with the 2–4 mm fraction replaced by half) and S3/2 (air-entrained). The application of an air-entraining agent is more expensive than LWA, and at a construction site it is not always easy to control. It seems that the replacement of a part of aggregate by LWA could be a more effective way to improve the scaling resistance.
Scaling resistance of high performance concretes containing a small portion of pre-wetted lightweight fine aggregate
AbstractThe subject of the investigation was the influence of pre-wetted lightweight aggregate on damage of the concrete surface due to cyclic freezing and thawing in the presence of de-icing salts tested according to the Swedish Standard SS 13 72 44 (the Borås method). Six series of concrete specimens were made with the same water/binder (w/b) ratio 0.32, cement volume 400kg/m3 and content of superplasticiser 8.8kg/m3. One series, S3/2, contained an air-entraining agent. Series S4/7 and S4/8 were made with water/cement ratio equal to 0.45 and a lower cement content 340kg/m3. In a few series the sand fraction 0–2mm and basalt fraction 2–4mm were partly or totally replaced by wetted lightweight aggregate. Concretes S3/1, S3/3, S4/7 and S4/8, failed the test. The best results were obtained for concrete S3/6 (with the 2–4 mm fraction replaced by half) and S3/2 (air-entrained). The application of an air-entraining agent is more expensive than LWA, and at a construction site it is not always easy to control. It seems that the replacement of a part of aggregate by LWA could be a more effective way to improve the scaling resistance.
Scaling resistance of high performance concretes containing a small portion of pre-wetted lightweight fine aggregate
Jóźwiak-Niedźwiedzka, Daria (author)
Cement and Concrete Composites ; 27 ; 709-715
2004-11-02
7 pages
Article (Journal)
Electronic Resource
English
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