Granite Powder vs. Fly Ash for the Sustainable Production of Air-Cured Cementitious Mortars.

Adrian Chajec

doi:10.3390/ma14051208

Abstract

The partial replacement of cement in concrete with the addition of granite powder and fly ash can help to reduce the carbon dioxide (CO2) emissions into the atmosphere associated with cement production. The aim of the article is to compare the performance of granite powder and fly ash for the sustainable production of air-cured cementitious mortars. The morphological, chemical, and granulometric properties of these additives were first compared with the properties of cement. Afterward, a series of mortars modified with the addition of granite powder and fly ash was made. The properties of the fresh mixes and the mechanical properties of the hardened composites were then tested. Finally, based on the obtained results, a cost analysis of the profitability of modifying cementitious composites with granite powder or fly ash was investigated. The obtained results allow similarities and differences between granite powder and fly ash in relation to cement to be shown. To conclude, it should be stated that both of these materials can successfully be used for the sustainable production of air-cured cementitious composites. This conclusion has a significant impact on the possibility of improving the natural environment by reducing the amount of cement production. More sustainable production of cement-based materials could enable CO2 emissions to be decreased. The use of granite powder for the production of cementitious mortars can significantly reduce the amount of this material deposited in landfills.

Highlights

Carbon dioxide (CO2) emissions into the atmosphere have been growing steadily for several decades [1,2]
The mortar with the addition of the granite powder has a lower value of compressive strength than the reference mortar, and its value decreases as the amount of cement replaced by the granite powder increases
The mortar with the addition of the fly ash has a lower value of compressive strength than the reference mortar, and its value decreases as the amount of cement being replaced by the fly ash increases

Summary

Introduction

Carbon dioxide (CO2) emissions into the atmosphere have been growing steadily for several decades [1,2]. Maddalena et al [18] described the possibility of producing green cement with the sustainable use of SCMs such as metakaolin, silica fume, and nano-silica Due to their high porosity and good thermal conductivity, carbon emissions in domestic construction could be reduced by 20–50%. Giergiczny [23] described the most commonly used types of fly ashes—siliceous fly ash, calcium fly ash, and fluidized bed combustion fly ash He compared the methods of activation of fly ash and its impact on the properties of fresh and hardened cement mixes. Golewski [22] conducted research concerning the impact of fly ash and curing conditions on fracture toughness and the cracking mechanism in concrete He observed that it is possible to make sustainable green concrete with the addition of fly ash with high mechanical properties.

Objectives

Methods

Results

Conclusion