Utilization of Waste Glass Cullet as Partial Substitutions of Coarse Aggregate to Produce Eco-Friendly Concrete: Role of Metakaolin as Cement Replacement

Abstract

The utilization of waste products is becoming a vital aspect of the construction industry to safeguard environmental assets and mitigate pollution, all of which lead to long-term sustainable development. From this perspective, this experimental investigation was carried out to determine the cumulative influence of waste glass cullet and metakaolin (MK) as partial replacements for coarse aggregates and cement in an isolated and combined manner. This research demonstrated the influence of integrating glass aggregate and metakaolin wherein coarse aggregate was substituted by 10%, 15%, 20%, 25%, and 30% glass cullet (by weight), and cement was supplemented with 10% metakaolin. The substitution of waste glass with coarse aggregate significantly declines the compressive strength correspondingly; however, the integration of 10% metakaolin powder enhanced the strength slightly for all specimens up to 25%. On the other hand, for flexural strength, the inclusion of glass waste in concrete reduced the performance, whereas the incorporation of metakaolin boosted the strength but did not achieve greater strength compared to the control mixture. The sustainability analysis revealed that the production cost and eCO2 emission could be reduced by 15% and 7% by incorporating glass cullet and metakaolin in the concrete mix, which satisfied sustainability. Based on the experimental results, the ideal proportion substitution would be 25% glass aggregate with 10% metakaolin, which could satisfactorily be used to generate sustainable concrete.

Eco-Friendly Sustainable Concrete and Mortar Using Coal Dust Waste

“…And the water absorption of concrete decreased by 9.7%, and for mortar it decreased by 9.3%. This is in good agreement with the works of a number of authors, in particular with the works [13][14][15][16][17][18][19] devoted to the processes of structure formation of concrete composites using coal dust and the works of the authors [20][21][22][23][24][25][26][27] devoted to the physical and mechanical characteristics of concrete modified with coal dust. Based on the results of XRD analysis of concrete of the control composition, the phases of portlandite, illite, anorite, calcite and quartz were identified.…”

“…It should be noted that, based on the results of the literature review, no studies were found on the use of coal dust with a similar chemical composition as a partial replacement for binders in the technology of cement composites. However, there are a number of studies [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] where the use of inert mineral additives, namely, clay, metakaolin, electric arc furnace dust, stone dust and finely ground sea shell powders, as a partial replacement for cement allows in rational amounts the improvement of the physical and mechanical characteristics of the composite and at the same time an increase in its environmental friendliness. The optimal percentages for replacing part of the cement with these types of additives varied from 2% to 20%, while improvements in the strength characteristics, water absorption and porosity of experimental cement composites were observed.…”

“…It should be noted that, based on the results of the literature review, no studies were found on the use of coal dust with a similar chemical composition as a partial replacement for binders in the technology of cement composites. However, there are a number of studies [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] where the use of inert mineral additives, namely, clay, metakaolin, electric arc furnace dust, stone dust and finely ground sea shell powders, as a partial replacement for cement allows in rational The use of coal dust of similar origin in the study [8] in small quantities-up to 2.5 wt.% of ordinary Portland cement-made it possible to improve the mechanical strength of cement composites by reducing open porosity and increased formation of hydration products compared to the reference ones. The prospect of the effective use of coal dust in appropriate, rationally selected quantities in the production of concrete was noted [8].…”

“…It was established that metakaolin in SCC at a rational quantity also has a positive effect on the strength, water absorption and porosity. The use of metakaolin as a partial replacement for cement in concrete technology was also studied in detail in [16][17][18][19]. It is noted that the use of this additive in rational quantities makes it possible to improve the strength characteristics and durability of composites and reduce their porosity and water absorption.…”

Artificial Neural Network-Based Prediction of Physical and Mechanical Properties of Concrete Containing Glass Aggregates

“…The substitution caused declines in the compressive strength that became significant with a high replacement ratio, with optimum compressive strength achieved at a 10% replacement ratio. The slump values showed a tendency to increase with an increase in glass aggregate [14]. Another study used recycled waste glass in proportions of 0-100% by weight to substitute sand in a 20 MPa-grade concrete mixture.…”