Alkali activated ground granulated blast-furnace slag concrete: Preliminary investigation

The Interfacial Transition Zone in Alkali-Activated Slag Mortars

“…So, moving along a line from the aggregate to the bulk paste as shown in the aggregated line scan data in Figure 4, in AAS mortar the proportion of outer products progressively decreases, while the inner products are less predominant than the outer product in the region close to the aggregate, increasing to reach nearly 70% in the bulk paste, consistent with the lower presence of slag particles remaining in this region. The width of the ITZ is larger than the usual size that is observed in PC-based mortars (~20 μm), which may be associated with a packing effect (Fernández-Jiménez et al, 1999) due to the slightly larger particle size distribution of the slag used here than most PCs. The presence of an ITZ enriched in reaction products is caused by the higher effective local water/binder ratio in this zone.…”

“…Alkali-activated slag (AAS) binders are currently the focus of many research studies, because concretes based on these binders may be environmentally preferable when compared to PC concrete, and can also provide attractive technical properties (Fernández-Jiménez et al, 1999;Shi et al, 2006;Bernal et al, 2011a;Van Deventer et al, 2012). Commercialization and industrial application of these products are becoming more widespread (Van Deventer et al, 2010, and the understanding of their chemical, mechanical, and durability behavior is becoming more advanced.…”

“…Commercialization and industrial application of these products are becoming more widespread (Van Deventer et al, 2010, and the understanding of their chemical, mechanical, and durability behavior is becoming more advanced. The alkali-activation of slag leads to the formation of a C-(A)-S-H type gel (Douglas et al, 1991;Scrivener and Nemati, 1996), with a Ca/Si ratio between 0.7 and 1.4, along with the formation of secondary reaction products such as zeolites and layered double hydroxide type phases, depending on the nature of the activator and the chemical composition of the slag used . In AAS concretes, it has also been observed that the ITZ between the matrix and the aggregate is highly dense and uniform San Nicolas et al, 2014), which is likely to contribute to the improvement of the mechanical strength and durability of these materials.…”

Preparation and Properties of Alkali-Activated Cement Containing Phosphorous Slag and Fly Ash

“…Alkaline cement has attracted widespread attention because of its simple production process, full utilization of industrial waste as raw materials, low pollution and good performance [1][2][3]. The mostly investigated waste for preparing alkaline cement is granulated blast furnace slag (GBFS), which has good potential hydraulic properties [4][5][6][7][8][9][10][11].…”

Dry powder alkali-activated slag cements

“…Intensive research and development of alkaliactivated slag (AAS) cements and concretes has been carried out in the USSR by Glukhovsky and co-workers since the 1950s (Glukhovsky, 1959;Glukhovsky et al, 1983). During the last two decades AAS cements and concretes have been intensively studied worldwide (Bakharev et al, 1999a(Bakharev et al, , 2000Ben Haha et al, 2011;Collins and Sanjayan, 1999b;Douglas et al, 1991;Douglas and Brandstetr, 1990;Fernández-Jiménez et al, 1999;Wang et al, 1994Ž ivica, 2007). Interest in these cements is driven not only by the need of human society to reduce the carbon dioxide emissions, but also by several advantages that AAS cements can offer.…”