Coupled thermodynamic modelling and experimental study of sodium hydroxide activated slag

In previous researches, the thermodynamic modelling of alkali-activated slag was conducted as a function of the degree of reaction of slag, which makes it difficult to compare the modelling results with the experimental results in a time scale. In this study, the reaction kinetics of sodium hydroxide activated slag was studied using...

Development and application of an environmentally friendly ductile alkali-activated composite

This paper presents a development of a ductile alkali-activated fly ash (FA) and ground granulated blast furnace slag (GBFS) based composite as an environmentally friendly material for structural concrete application. For this purpose, polyvinyl alcohol (PVA) fibres and sand aggregate were combined with alkali-activated paste. Workability,...

Effect of natural carbonation on the pore structure and elastic modulus of the alkali-activated fly ash and slag pastes

The aim of this paper was to investigate the effect of natural carbonation on the pore structure, and elastic modulus (E_m) of alkali-activated fly ash (FA) and ground granulated blast furnace slag (GBFS) pastes after one year of exposure in the natural laboratory conditions. The chemical changes due to carbonation were examined by...

CO2 binding capacity of alkali-activated fly ash and slag pastes

Quantification of the CO2 binding capacity of reinforced concrete is of high<br/>importance for predicting the carbonation potential and service life of these structures. Such information is still not available for alkali activated materials that have received extensive attention as a sustainable substitute for ordinary Portland cement (OPC)...

Setting, Strength, and Autogenous Shrinkage of Alkali-Activated Fly Ash and Slag Pastes: Effect of Slag Content

The engineering properties of alkali activated materials (AAMs) mainly depend on the constituent materials and their mixture proportions. Despite many studies on the characterization of AAMs, guidelines for mixture design of AAMs and their applications in engineering practice are not available. Extensive experimental studies are still necessary...

Carbonation Resistance of Alkali-Activated Slag Under Natural and Accelerated Conditions

In this paper, carbonation resistance of alkali-activated slag (AAS) pastes exposed to natural and accelerated conditions up to 1 year was investigated. Two aspects of carbonation mechanism were evaluated. The first was the potential carbonation of the main binding phases in finely powdered AAS pastes. The second was the reactivity and...

Optimization of a geopolymer mixture for a reinforced cantilever concrete bench

A Review on the Durability of Alkali-Activated Fly Ash/Slag Systems: Advances, Issues, and Perspectives

Alkali-activated materials (AAMs) have high potential as alternative binder to ordinary portland cement (OPC), because of their high performance beside lower CO₂ emissions. While there is a general consensus about their strength advantages over OPC, there is a widespread debate regarding their durability. Some groups believe that...

Thermodynamic modeling and experimental study of alkali-activated slag paste

A newly developed thermodynamic approach was introduced from the literature to investigate the influence of NaOH content on the hydrate assemblage and chemistry of aqueous solution of activated slag paste (Na2O/slag=4%, 6% and 8%). The ICP-OES test was performed to obtain the aqueous species profiles such as Si, Ca, Al and Na etc. The elemental...

Microstructural and Mineralogical Analysis of Alkali Activated Fly Ash-Slag Pastes

The performances of alkali activated materials (AAM) are strongly related to their microstructures. The microstructure development is mainly affected by chemistry of the primary raw materials. In the present study the influence of different proportions of fly ash and slag (100:0, 70:30, 50:50, 30:70, 0:100 wt.%, named S0, S30, S50, S70, S100,...

Durability of alkali-activated fly ash and slag concrete

Alkali-activated materials (AAM) have received increasing interest during the past few decades due to their environmental and technological advantages. However the durability of these binders is still considered as an unproven issue that needs to be addressed before their commercial adoption and large-scale production. The present work is...

Reaction Kinetics and Thermodynamic Modeling of Sodium Hydroxide Activated Slag Paste

The technology of alkaline activation of calcium aluminosilicate materials, as an alternative to Portland cement to produce a clinker-free material, can address the energy and environmental concerns associated with Portland cement production. As this technology attracts more and more attention in recent years, there are increasing researches...