scholarly journals Sustainable low-carbon binders and concretes

2020 ◽  
Vol 166 ◽  
pp. 06007
Author(s):  
Myroslav Sanytsky ◽  
Tetiana Kropyvnytska ◽  
Stanislav Fic ◽  
Hanna Ivashchyshyn
Keyword(s):  
Activity Index ◽  
Chemical Properties ◽  
High Volume ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Cement Matrix ◽  
Low Carbon ◽  
Blended Cements ◽  
Physical And Chemical

Sustainable development depends on a consistency of interests, social, ecological and economic, and that the interests are evaluated in a balanced manner. In order to reduce CO2 emissions, the conception of decreasing clinker factor and increasing the role of supplementary cementitious materials (SCMs) in the cementitious materials has high economical and environmental efficiency. The performance of clinkerefficient blended cements with supplementary cementitious materials were examined. The influence of superfine zeolite with increased surface energy on the physical and chemical properties of low-carbon blended cements is shown. Increasing the dispersion of cementitious materials contributes to the growth of their strength activity index due to compaction of cement matrix and pozzolanic reactions in unclincker part. In consequence of the early structure formation and the directed formation of the microstructure of the cement matrix is solving the problem of obtaining clinker-efficient concretes. Shown that low-carbon blended cements with high volume of SCMs are suitable, in principle, for producing structural concretes.

scholarly journals Eco-efficient blended cements with high volume supplementary cementitious materials

2020 ◽  
Vol 18 (4) ◽  
pp. 005-014
Author(s):  
Myroslav Sanytsky ◽  
Tetiana Kropyvnytska ◽  
Hanna Ivashchyshyn ◽  
Оksana Rykhlitska
Keyword(s):  
Development Strategy ◽  
Optimal Solution ◽  
High Volume ◽  
Cementitious Materials ◽  
Economic Benefits ◽  
Cement Industry ◽  
Supplementary Cementitious Materials ◽  
Low Carbon ◽  
Blended Cements ◽  
Granulated Blast Furnace Slag

The ways of reducing CO2 emissions in the cement industry were analysed for the purposes of implementation of the low carbon development strategy. The optimal solution to this problem is the technologically optimised blended cements with high volume of supplementary cementitious materials of various genesis and fineness. The design of eco-friendly blended cements was achieved by a synergistic combination of the main constituents such as granulated blast furnace slag, superfine zeolite, fly ash and limestone, as well as by optimisation of the their granulometric composition, taking into account their bimodal particle size distribution by volume and surface area. Moreover, the article presents the technical, environmental and economic benefits of using eco-efficient blended cements.

scholarly journals Utilization of Waste Glasses as Supplementary Cementitious Materials

2021 ◽  
Vol 9 (2) ◽  
pp. 79-83
Author(s):  
Yousif Hummaida Ahmed ◽  
Mohamed Ibrahim ◽  
Duaa Soliman
Keyword(s):  
Glass Powder ◽  
Activity Index ◽  
Chemical Properties ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Local Source ◽  
Insoluble Residue ◽  
Colored Glass ◽  
Pozzolanic Material ◽  
Glass Wastes

Wastes of Glass are recognized as pozzolanic material. This study aims to investigate utilization of local glass wastes in Sudan as supplementary cementitious materials. Two glass wastes specimens having different colors are procured from a local source namely Sudanese Emirati Glass and Metal Company (SEGMAL). Then thy are ground to micro sizes producing two types of glass powders, clear white glass powder (W-GP) and colored glass powder (C-GP). The two Specimens are characterized using tests specified in American Society for Testing and Materials ASTM C311. These tests include chemical properties using X-ray Fluorescence (XRF), Loss on Ignition (LOI), Insoluble Residue (IR), also physical properties such as fineness, specific gravity, water requirement, and strength activity index (SAI). This study shows that at 7 days W-GP and C-GP produced SAI of 84% and 87% at 7-days respectively. These values are more than the 75% of SAI’s requirements of ASTM C618. Both specimens have outperformed the control OPC mix at 28 days by producing SAI of 108.68% and 123.82% for GP-W and GP-C respectively.  

scholarly journals The Effect of SCMs in Blended Cements on Sorption Characteristics of Superabsorbent Polymers

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1609
Author(s):  
Rohollah Rostami ◽  
Agnieszka J. Klemm ◽  
Fernando C. R. Almeida
Keyword(s):  
Portland Cement ◽  
Chemical Properties ◽  
Blended Cement ◽  
Cementitious Materials ◽  
Absorption Capacity ◽  
Supplementary Cementitious Materials ◽  
Partial Replacement ◽  
Chemical Compositions ◽  
Superabsorbent Polymers ◽  
Blended Cements

Supplementary cementitious materials (SCMs), such as fly ash (FA) and ground granulated blast-furnace slag (GGBS), are often used as a partial replacement of cements to improve the sustainability of Portland cement-based materials and reduce their environmental impact. Superabsorbent polymers (SAPs) can be successfully used as internal curing agents in ultra-high performance cementitious materials by facilitating the hydration process and controlling the water supply in both fresh and hardened states. This paper intends to characterise the physical and chemical properties of SAPs and their sorption properties in different blended cement environments. The swelling capacity and kinetics of absorption of three superabsorbent polymers with different chemical compositions and grading were tested in different cement environments. Experimental results of their sorption performance in distinct solutions, including deionised water (DI), Portland cement (PC), and blended cements (PC-FA and PC-GGBS) and changes in pH of different solutions over time were investigated. The results showed that PC-FA solution had the lowest pH followed by PC-GGBS solution. Moreover, SAPs samples displayed the highest absorption capacities in PC-FA solutions, and the lowest swelling capacities were found in PC-GGBS solutions. Furthermore, SAP with smaller particle sizes had the greatest absorption capacity values in all solutions.

From composition to the microstructure and durability of limestone ternary blended cements: A Systematic review

2021 ◽  
pp. 1-44
Author(s):  
Samuel Adu-Amankwah ◽  
Suraj Rahmon ◽  
Leon Black
Keyword(s):  
Large Scale ◽  
Air Entrainment ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Chloride Ingress ◽  
Blended Cements ◽  
Freeze Thaw ◽  
Significant Research ◽  
Large Scale Field

Limestone ternary cements have attracted significant research and commercial attention recently, for technical and environmental reasons. Standardization of these cements is imminent under BS EN197-5. Presently, detailed understanding of the hydration and microstructure evolution of limestone ternary cements from different alumina-rich supplementary cementitious materials (SCMs) exists in the scientific literature; improved reaction kinetics and additional phase assemblages refine the pore structure. However, understanding of the performance of these cements under exposure conditions is less prevalent. In this contribution, we review these data in a way that allows stakeholders to appreciate the capabilities of the different compositions and their performance. We focus our discussion on critically examining the interplay between the cement composition and the microstructure on durability. It is demonstrated that limestone ternary cements offer a pathway for reducing the embodied CO2 of concrete without compromising their performance. The resistance to chloride ingress, sulphate attack and ASR are significantly improved in a manner similar to binary cements. Carbonation and freeze-thaw resistance is generally lower than OPC but adequate air entrainment can offer improvement in freeze-thaw resistance. The challenge to widespread adoption of these cements is evidence of durability under field conditions. To this end, we recommend large-scale field trialling of these cements and understanding of the role of combined exposures on durability and mechanical properties.

A state-of-the-art review on the durability of silica fume-blended concrete – a boon to the construction industry

2013 ◽  
Vol 31 (3-6) ◽  
pp. 123-134 ◽  
Author(s):  
Velu Saraswathy ◽  
Subbiah P. Karthick
Keyword(s):  
Construction Industry ◽  
Silica Fume ◽  
Blended Cement ◽  
Cementitious Materials ◽  
Supplementary Cementitious Materials ◽  
Cement Matrix ◽  
Conservation Of Resources ◽  
Chloride Permeability ◽  
Conventional Concrete ◽  
Blended Cements

AbstractThe development and use of blended cement is growing rapidly in the construction industry mainly due to the consideration of energy, environment, and conservation of resources. Blended cements are produced using any of the supplementary cementitious materials such as silica fume (SF), fly ash, and ground granulated blast furnace slag. The use of SF in concrete may improve the strength and durability of concrete by creating a denser cement matrix compared with conventional concrete, thereby enhancing the service life of concrete structures. In this article, the effect of SF in concrete is reviewed from the point of view of durability. It includes carbonation, resistivity, chloride permeability/diffusivity, sulfate resistance, and corrosion resistance.

scholarly journals Waste Tire Particles and Gamma Radiation as Modifiers of the Mechanical Properties of Concrete

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Eduardo Sadot Herrera-Sosa ◽  
Gonzalo Martínez-Barrera ◽  
Carlos Barrera-Díaz ◽  
Epifanio Cruz-Zaragoza
Keyword(s):  
Mechanical Properties ◽  
Gamma Radiation ◽  
Chemical Properties ◽  
Plain Concrete ◽  
Cement Matrix ◽  
Portland Cement Concrete ◽  
High Concentration ◽  
Good Tool ◽  
Waste Tire ◽  
Physical And Chemical

In polymer reinforced concrete, the Young’s modulus of both polymers and cement matrix is responsible for the detrimental properties of the concrete, including compressive and tensile strength, as well as stiffness. A novel methodology for solving such problems is based on use of ionizing radiation, which has proven to be a good tool for improvement on physical and chemical properties of several materials including polymers, ceramics, and composites. In this work, particles of 0.85 mm and 2.80 mm obtained from waste tire were submitted at 250 kGy of gamma radiation in order to modify their physicochemical properties and then used as reinforcement in Portland cement concrete for improving mechanical properties. The results show diminution on mechanical properties in both kinds of concrete without (or with) irradiated tire particles with respect to plain concrete. Nevertheless such diminutions (from 2 to 16%) are compensated with the use of high concentration of waste tire particles (30%), which ensures that the concrete will not significantly increase the cost.

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