A chemical/mineralogical investigation of the behavior of sulfoaluminate binders submitted to accelerated carbonation

Autor: Sabine Mutke, Enrico Boccaleri, Geo Paul, Daniela Gastaldi, S. Irico, Federica Bertola, Leonardo Marchese, Fulvio Canonico, Luigi Buzzi
Rok vydání: 2018
Předmět:
Zdroj: Cement and Concrete Research. 109:30-41
ISSN: 0008-8846
Popis: The paper addresses the carbonation of CSA based binders from the mechanical, chemical and mineralogical point of view. Three different binders have been investigated, revealing that many hydrated phases can protect ettringite against carbonation. In particular, the presence of AFm phases gives a significant contribution to buffer the pH in alkaline range and to preserve the protective film of steel reinforcement bars. In a carbonated environment AFm phases act as ionic exchangers: carbonate ions replace sulfates in the interlayer and in these conditions the released sulfate ions contribute to the formation of new ettringite, with a beneficial effect on compressive strength performances. Experimental data are compared with models and carbonation mechanisms are described.
Databáze: OpenAIRE