resumo
The use of metakaolin is known to help improve properties of Portland cement-based mortars. The presumed similarities between the characteristics of metakaolin and those of a powdered (<45 mu m) fired clay brick clean waste (CBW) led to the investigation of the effect on the durability of mortars of partial replacement (10, 25 and 40 wt.%) of Portland cement by CBW. Properties such as 28 and 90 days-compressive strength, water absorption, apparent porosity, absorption by capillarity, chloride retention, carbonation depth and sulphate resistance were evaluated. The CBW-containing cured mortars showed improved strength and density, as the result of combined physical and pozzolanic pore filling effect of added CBW. However, CBW-free mortar exhibited larger spreading and, being more porous, higher sulphate resistance and ability to absorb chlorides. Optimum performance was found for the 40 wt.% CBW mortar whose compressive strength can be up to 130% higher than that of the CBW-free mortar. (C) 2015 Elsevier Ltd. All rights reserved.
palavras-chave
NATURAL POZZOLANS; CONCRETE; METAKAOLIN; RESISTANCE; BEHAVIOR; PERFORMANCE; CARBONATION; KAOLINITE; CHLORIDE; KINETICS
categoria
Construction & Building Technology; Materials Science
autores
Schackow, A; Stringari, D; Senff, L; Correia, SL; Segadaes, AM
nossos autores
Ana Maria B C Segadães
Professor(a) Jubilado(a)agradecimentos
Authors appreciate the financial support received from CAPES (Brazilian Federal Agency for the Support and Evaluation of Graduate Education) and the State University of Santa Catarina (Science initiation scholarship, Douglas Stringari).