Chloride Ions Penetration of Alkali-Activated Fly Ash Mortars with Ground Granulated Blast Furnace Slag / Patrycja Duży, Mateusz Sitarz, Marcin Adamczyk, Marta Choińska, Izabela Hager // W: Concrete ... więcej

Chloride Ions Penetration of Alkali-Activated Fly Ash Mortars with Ground Granulated Blast Furnace Slag / Patrycja Duży, Mateusz Sitarz, Marcin Adamczyk, Marta Choińska, Izabela Hager // W: Concrete Structures: New Trends for Eco-Efficiency and Performance : proceedings of the fib Symposium 2021 held online from Lisbon, Portugal, 14-16 June 2021 [Dokument elektroniczny] / ed. by E. Júlio, J. Valença, A.S. Louro. – Lisbon : Fédération Internationale du Béton (fib), 2021. – Pamięć USB. – (fib Symposium Proceedings, ISSN 2617-4820 ; 54). – S. 284-293 : fot., rys., schem., tab., wykr. – Bibliogr. s. 293, Abstr. – Miejsce wyd. wg miejsca konf. – Wydaw. wg cop. – Data wyd. wg daty konf. – ISBN 978-2-940643-08-0

Due to the need to reduce the CO2 emissions of natural binders researchers are considering the use of alkali-activated materials (AAMs) as an alternative to traditional cementitious binders. The properties ... więcej

Due to the need to reduce the CO2 emissions of natural binders researchers are considering the use of alkali-activated materials (AAMs) as an alternative to traditional cementitious binders. The properties of AAMs (e.g. low shrinkage and fire resistance) can be more advantageous to those presented by cementitious binders, and thus they can replace Portland cement binders in some applications. Durability tests of AAMs are conducted on an ongoing basis; however, durability issues related to the protection of reinforcing steel in conditions in which steel members interact with chloride ions remain unsolved. Additionally, the mechanism of chloride transport in these materials receives great attention as do factors affecting chloride migration in AAM composites. In this paper, the precursors for AAM preparations are blends of fly ash (FA) and ground granulated blast-furnace slag (GGBFS) in four proportions’ 0, 10, 30, and 50%. Four mortars were prepared, denominated as AAM 0, AAM 10, AAM 30 and AAM 50, respectively. Their basic physical and mechanical characteristics were investigated as were their gas transport properties. The nitrogen Cembureau method was applied to determine the permeability of the mortar. The chloride ions transport properties were determined using modified NT BUILD 492 Migration Test. The modification consisted of lower voltage application 10 V - as recommended by Noushini and Castel [2018]. The comparison of results obtained for AAM 0, AAM 10, AAM 30 and AAM 50 have demonstrated a positive effect of GGBFS addition in term of bulk density increase, at the same time reduction of chloride ion penetration. The water absorption tests also provided insight in the open pore structures of mortars. The measurements revealed a strong dependence between fluid transport through the mortars and water absorption and the initial water content of materials.