Physical-chemical characteristics of an eco-friendly binder using ternary mixture of industrial wastes

Abstract

This study explores the physical-chemical characteristics of paste and mortar with an eco-friendly binder named as SFC cement, produced by a ternary mixture of industrial waste materials of ground granulated blast furnace slag (S), Class F fly ash (FFA), and circulating fluidized bed combustion fly ash (CFA). To trigger the hydration, the CFA, which acted as an alkaline-sulfate activator, was added to the blended mixture of slag and FFA. The water to binder ratio (W/B), curing regime, and FFA addition significantly affected the engineering performances and shrinkage/expansion of the SFC pastes and mortars. The SFC mortars had higher workability than that of ordinary Portland cement (OPC). With similar workability, the SFC mortars had compressive strengths and expansions comparable to OPC mortars. The main hydration products of the hardened SFC cement were ettringite (AFt) and C-S-H/C-A-S-H. The transformation of the AFt to the monosulfates was observed as the hydration time increased.

Utilization of artificial lightweight aggregate and unground rice husk ash as internal curing agents to modify performance of super-sulfated cement mortar

“…Recently, productions of environmentally friendly SSCs containing calcium sulfate derived from various industrial by-products such as flue gas desulfurization gypsum and circulating fluidized bed combustion ashes receive a serious consideration from the modern cement/concrete industries to persuade the sustainability development [8]. But, the mechanical properties of the low energy SSCs were obviously unsatisfactory to be widely applied for construction fields where the OPC has been properly used [9][10][11] For enhancing the SSC performance, instead of adapting physicochemical treatment, lowering water content in the SSC proportions seems to be the most preferable consideration to minimize the cost [11], which possibly led to increased risk of shrinkage issue induced by self-desiccation phenomenon as subsequently described [12].…”

Influence of internal curing on compressive strength and drying shrinkage of super-sulfated cement mortar

“…However, for persuading a concept of durability development, environmentally friendly SSCs including various industrial wastes rich in calcium sulfate have become research interests (Chen et al, 2015). Apparently, the mechanical performance of such kind of binder is lower than that of the OPC, which led to its' limit for widespread use in the construction fields (Nguyen et al, 2015;Nguyen et al, 2020;Nguyen et al, 2016). To achieve a proper modification on the SSC performance, reducing the water content in the resultant productions was seemly the most preferable cutting the cost (Nguyen et al, 2015).…”

“…Apparently, the mechanical performance of such kind of binder is lower than that of the OPC, which led to its' limit for widespread use in the construction fields (Nguyen et al, 2015;Nguyen et al, 2020;Nguyen et al, 2016). To achieve a proper modification on the SSC performance, reducing the water content in the resultant productions was seemly the most preferable cutting the cost (Nguyen et al, 2015). As such, an issue associated with increased risk of shrinkage induced by the selfdesiccation phenomenon occurred.…”