Effect of sepiolite addition on fibre-cement based on MgO-SiO2 systems

Author(s)

Marmol, Gonzalo ^[1] ; Savastano, Jr., Holmer ^[1] ; de la Fuente, Elena ^[2] ; Miranda, Ruben ^[2] ; Blanco, Angeles ^[2] ; Negro, Carlos ^[2]

Affiliation

^[1] Univ Sao Paulo, Fac Anim Sci & Food Engn, Dept Biosyst Engn, Duque Caxias Norte St 225, BR-13630000 Pirassununga, SP - Brazil

^[2] Univ Complutense Madrid, Dept Chem Engn, Avda Complutense S-N, Madrid 28040 - Spain

• Document type: Journal article
• Source: CEMENT AND CONCRETE RESEARCH; v. 124, OCT 2019.
• Web of Science Citations: 0

Abstract

The addition of sepiolite in fibre-cement is analysed as a possible additive constituent of MgO-SiO2 binders. In order to optimise the Mg-SiO2 cementitious system in fibre-cement sheets, small cement replacement (1 and 2 wt %) by sepiolite is introduced and its effects are studied, firstly, in hardened cement pastes and, later, in fibre-cement systems. When used only in cement pastes, non-destructive studies are employed to assess flexural performance over time as well as the possible reactivity between additive and cement, proving that Elastic Modulus is increased. When sepiolite is introduced in fibre-cement, the properties of the slurry suspensions and its interference in the Hatschek process are studied. It is shown that sepiolite addition increases floc size of MgO-SiO2 systems. Finally, flexural tests are performed to understand the outcome of this additive of the mechanical performance of the samples, proving that sepiolite improves the product homogeneity, which is essential for industrial applications. (AU)

• FAPESP's process: 12/51467-3 - Agroindustrial wastes and their potential use as appropriate materials for housing and infraestructure (Agrowaste)
• Grantee: Holmer Savastano Junior
• Support Opportunities: Research Projects - Thematic Grants