Memoria tratta da "The New Boundaries of Structural Concrete: Session B – Controlled-performance Concrete", ACI IC - Ancona 2011
Self-compacting lightweight concrete was developed to attain good workability, high compressive strength (Rck about 40 Mpa), minimum cracks, effective durability even in very aggressive exposures, and low specific weight (about 2000 kg/m3), as well as low elastic modulus (about 30 GPa). Concrete was evaluted in the fresh state as well as in the hardened state by measuring compressive strength, restrained expansion, carbonation and chloride penetration, and dynamic elastic modulus. This concrete should be particularly suitable in meeting the specific requirements of concrete used in seismic areas. The present paper shows the results of the preliminary trial tests to attain these objectives by using high-quality raw materials available during the last decade: polycarboxylate admixture (PCA) as superplasticizer, shrinkage-reducing admixture (SRA), CaO-based expansive agent, PVA (What is PVA? Please provide full name the first time it is used.) fibres, expanded clay to reduce the specific weight under 2000 kg/m3, and ground limestone filler to manufacture uniform self-compacting concrete without bleeding and segregation. Many of these objectives for properties were attained by using about 400 kg /m3 of portland cement, about 100 kg/m3 of limestone filler, 900 kg/m3 of coarse sand (0-8 mm), 400 kg/m3 of expanded clay (0-15 mm), 12 kg/m3 of PCA, 4 kg/m3 of SRA, 30 kg/m3 of the expansive agent, and 4 kg/m3 of PVA fibres.
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