LADLE FURNACE SLAG REPLACEMENT ON THE FLEXURAL STRENGTH OF THIN FLY ASH GEOPOLYMER

The feasibility of using EAF slag aggregate, fly ash, and silica fume in pavement Electric Arc Furnace Slag Concrete (CEAFS) is the focus of this research. EAF slag aggregate is volume stable and suitable for use in concrete, according to the findings of the testing. EAF slag was utilized to replace natural coarse aggregates in the CEAFS mixes. CEAFS was created by blending 50% crushed stone with 50% EAF slag in coarse aggregates, with fly ash (FA) and silica fume (SF) partially replacing cement at content levels (i.e. FA: 0, 20, 30, and 40%; SF: 0, 5, and 10%). The soil compaction approach was used to evaluate the optimal moisture level for CEAFS mixes containing EAF slag aggregate fly ash and silica fume. A testing program was used to investigate the weight of CEAFS units and their mechanical qualities (compressive strength, flexural strength, and elastic modulus). As a result, the fresh and hardened unit weights in the CEAFS are comparable. Moreover, variations in the concentration of mineral additives FA and SF in adhesives, as well as the CEAFS mixed aggregate ratio, have an impact on compressive strength, flexural strength, and elastic modulus at all ages. However, combining EAF slag aggregate with (FA0% +SF10%; FA10% +SF0%; FA10% +SF10%; and FA20% +SF10%) the CEAFS mixtures have improved mechanical characteristics over time. According to this study, CEAFS pavements can be made with EAF slag aggregate fly ash and silica fume. In addition, a formula correlation was suggested to compute CEAFS (i.e. compressive strength with elastic modulus and compressive strength with flexural strength). Doi: 10.28991/cej-2021-03091755 Full Text: PDF

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Properties of GGBFS-Based Pervious Concrete Containing Fly Ash and Silica Fume

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.266.278 ◽

2017 ◽

Vol 266 ◽

pp. 278-282 ◽

Cited By ~ 3

Author(s):

Jul Endawati

Keyword(s):

Compressive Strength ◽

Blast Furnace ◽

Fly Ash ◽

Flexural Strength ◽

Silica Fume ◽

Blast Furnace Slag ◽

Aggregate Size ◽

Pervious Concrete ◽

Fine Aggregate ◽

Furnace Slag

Pervious concrete primarily is used as a means of storm water management. Taking into consideration the environment issues, the binder can also be formed by partially replaced Portland cement by cementitious materials, such as blast furnace slag fine powder, fly ash and silica fume. The combination of the binder materials was determined based on previous work, which composed of 56% Portland Composite Cement, 15% fly ash Type F, 26% air-cooled blast furnace slag from a local steel Industry and 3% condensed silica fume. The compressive strength of specimens with coarser aggregate was lower compared with the control pervious concrete, but still within the range of the requirement compressive strength according to ACI 522R-2010. The difference of the aggregate size affected the enhancement of the compressive strength. The flexural strength of pervious concrete with aggregate size of 9.5mm-12.5mm tend to be higher compared with that of pervious concrete with smaller aggregate size. Furthermore, the addition of 6% natural fine aggregate while applying higher water/cement ratio could be a contribution to the enhancement of the compressive and the flexural strength.

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Effect of High Calcium Fly Ash, Ladle Furnace Slag, and Limestone Filler on Packing Density, Consistency, and Strength of Cement Pastes

Materials ◽

10.3390/ma14020301 ◽

2021 ◽

Vol 14 (2) ◽

pp. 301

Author(s):

Eleftherios K. Anastasiou

Keyword(s):

Fly Ash ◽

Cementitious Materials ◽

Supplementary Cementitious Materials ◽

Strength Development ◽

Ladle Furnace ◽

Limestone Filler ◽

Cement Pastes ◽

High Calcium ◽

High Calcium Fly Ash ◽

Furnace Slag

Environmental considerations and technical benefits have directed research towards reducing cement clinker content in concrete, and one of the best ways to do this is to replace cement with supplementary cementitious materials. High calcium fly ash, ladle furnace slag, and limestone filler were investigated as supplementary cementitious materials in cement pastes, and binary mixtures were produced at 10%, 20%, and 30% cement replacement rates for each material. The water requirement for maximum packing and for normal consistency were obtained for each paste, and strength development was determined at 3, 7, 28, and 90 days for the 20% replacement rate. Furthermore, two ternary mixtures at 30% cement replacement were also prepared for maximum packing density and tested for compressive strength development. The results showed that high calcium fly ash decreased cement paste packing and increased water demand but contributed to strength development through reactivity. Ladle furnace slag and limestone filler, on the other hand, were less reactive and seemed to contribute to strength development through the filler effect. The ternary paste with 70% cement, 20% high calcium fly ash, and 10% limestone filler showed equivalent strength development to that of the reference cement paste.

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Use of Ladle Furnace Slag and Other Industrial By-Products to Encapsulate Chloride in Municipal Solid Waste Incineration Fly Ash

Materials ◽

10.3390/ma12060925 ◽

2019 ◽

Vol 12 (6) ◽

pp. 925 ◽

Cited By ~ 1

Author(s):

Ying Wang ◽

Wen Ni ◽

Prannoy Suraneni

Keyword(s):

Fly Ash ◽

Municipal Solid Waste ◽

Solid Waste ◽

Waste Incineration ◽

Material System ◽

Ladle Furnace ◽

Municipal Solid Waste Incineration ◽

Friedel’S Salt ◽

Furnace Slag ◽

Waste Incineration Fly Ash

Municipal solid waste incineration fly ash (MSWIFA) is a hazardous by-product of waste incineration. The objective of this research is to encapsulate the chloride in MSWIFA and to develop a utilizable construction material using MSWIFA, ground granulated blast-furnace slag (GGBFS), ladle furnace slag (LFS), and gypsum. A secondary objective of the work is to explain the hydration and encapsulation mechanisms in this material system using isothermal calorimetry (IC), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and ion chromatography (IC). The predominant hydration products are ettringite, Friedel’s salt, and C-S-H gel, with Friedel’s salt and C-S-H dominating in systems high in LFS and ettringite and C-S-H gel dominating in systems low in LFS. The chloride encapsulation showed a strong correlation with the Friedel’s salt amount; however, some encapsulation was also likely due to physical binding in the C-S-H gel. In a system with 30% MSWIFA (by mass), the optimal amount of LFS for strength and chloride encapsulation is 20%–40% (by mass).

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Comparison of the strength development of binary and ternary cements containing perlite powder

Selected Scientific Papers - Journal of Civil Engineering ◽

10.1515/sspjce-2020-0006 ◽

2020 ◽

Vol 15 (1) ◽

pp. 47-57

Author(s):

Alena Sičáková ◽

Erika Figmigová ◽

Matej Špak

Keyword(s):

Compressive Strength ◽

Blast Furnace ◽

Fly Ash ◽

Flexural Strength ◽

Blast Furnace Slag ◽

Time Development ◽

Blended Cements ◽

Granulated Blast Furnace Slag ◽

Rate Of Increase ◽

Furnace Slag

Abstract Currently, the consumption of blended cements is increasing all over the world. This is due to environmental, technical and economic reasons. Among the additives mixed with ordinary Portland cement, ground granulated blast furnace slag and fly ash are of particular significance. However, some regions may lack standard additives, and vice versa, may be rich in natural pozzolans. This paper is focused on the perlite as a natural pozzolanic material which is locally available. This study presents the results of the application of perlite as a component of blended cements in different proportions, representing binary and ternary compositions, and compares it with standard additives (fly ash and ground granulated blast furnace slag). The time development of both compressive and flexural strength, including results of 2, 7, 28 and 90-day testing, is analyzed. Perlite binders show acceptable time development of strengths, which is comparable to conventional blended binders based on ground granulated blast furnace slag and fly ash and do not constitute a technological barrier. With a higher dose of perlite, the time increase in flexural strength is slower, but the rate of increase in compressive strength does not change substantially. Flexural strength of 4.1–6.2 MPa and compressive strength of 18.8–38.5 MPa are sufficient for a number of practical applications and are expected to meet the required limits. An improvement of strengths in the later period (90 days) was also confirmed.

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Experimental Study and Prediction Model of the Flexural Strength of concrete Containing Fly Ash and Ground Granulated Blast-Furnace Slag

Advances in Civil Engineering ◽

10.1155/2021/8773664 ◽

2021 ◽

Vol 2021 ◽

pp. 1-16

Author(s):

Hua Zhang ◽

Qing-Fu Li ◽

Hua-De Zhou ◽

Zong-Ming Song

Keyword(s):

Blast Furnace ◽

Fly Ash ◽

Flexural Strength ◽

Prediction Model ◽

Blast Furnace Slag ◽

Early Stage ◽

Support Vector ◽

Granulated Blast Furnace Slag ◽

Svm Model ◽

Furnace Slag

Orthogonal experiments were performed to study the flexural strength of an eco-friendly concrete containing fly ash (FA) and ground granulated blast-furnace slag (GGBFS). The effects of different test parameters, such as water-binder ratio (W/B), FA content, GGBFS content, sand ratio, gravel gradation, and curing time, on the flexural strength of the concrete were analyzed. The significance level of each influencing factor and the optimal mixing proportion of the concrete were determined by range analysis and hierarchy analysis. It was found that the W/B ratio had the greatest influence on the flexural strength of the concrete. The flexural strength of the concrete decreased gradually with the increase of W/B. The GGBFS content and the sand ratio had a greater influence in the early stage of concrete curing. The middle and later stages of concrete curing were mainly affected by gravel gradation and the FA content. A flexural strength prediction model of the concrete was developed based on a backpropagation neural network (BPNN) and a support vector machine (SVM) model. It was noticed that the BPNN and SVM models both had higher accuracy than the empirical equation, and the BPNN model was more accurate than the SVM model.

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Effect of Admixtures on Durability Characteristics of Fly Ash Alkali-activated Material

Emerging Science Journal ◽

10.28991/esj-2020-01247 ◽

2020 ◽

Vol 4 (6) ◽

pp. 493-502

Author(s):

Lukáš Procházka ◽

Jana Boháčová

Keyword(s):

Compressive Strength ◽

Blast Furnace ◽

Fly Ash ◽

Flexural Strength ◽

Frost Resistance ◽

Granulated Slag ◽

Furnace Slag ◽

Alkali Activated ◽

Reference Mixture ◽

Denitrification Process

This paper deals with the possibility of partial replacement of blast furnace slag with fly ash and fly ash after denitrification by SNCR method in alkali-activated materials based on granulated blast furnace slag. The aim of this paper is to verify the effect of fly ash on properties of alkali-activated materials based on blast furnace granulated slag. Frost resistance and resistance to aggressive environments, represented by demineralized water were tested. The reference mixture was based on blast furnace granulated slag activated by sodium water glass with silicate modulus of 2. Mixtures with an ash content of 10, 20, and 30% were then compared with the reference mixture. The influence of the denitrification process on fly ash and its use in mixed alkali activated materials was also compared. As a part of the experiment, alkali-activated pastes were also prepared. Infrared spectroscopy with Furier transformation was subsequently determined on these pastes. The reference mixture achieved the highest compressive strength in the experiment and the strength decreased with increasing amount of fly ash. In terms of flexural strength, the highest values were reached for mixtures with 10% slag replacement by fly ash. In the case of frost resistance, the significant increase of flexural strength, which was 50% for the reference mixture, is particularly interesting. For compressive strength, the frost resistance coefficient ranged from 0.95 to 1.00. In the case of resistance to aggressive environments, no differences were observed in the compressive strength, on the other hand, flexural strength decrease of up to 20% was detected for 10 and 20 percent replacement of slag with fly ash that did not undergo denitrification. Monitored properties did not show any negative effect of the denitrification process on fly ash properties. Infrared spectroscopy identified the main hydration product in the region of 945 cm-1which is a C-(A)-S-H gel and in combined mixtures with fly ash also N-A-S-H gel. Doi: 10.28991/esj-2020-01247 Full Text: PDF

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Experimental Investigation on Properties of High Performance Concrete with Mineral Admixtures in Pavement of Highway

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.723.345 ◽

2013 ◽

Vol 723 ◽

pp. 345-352

Author(s):

Le Hua Yu ◽

Shuang Xi Zhou ◽

Hui Ou

Keyword(s):

Fly Ash ◽

Flexural Strength ◽

High Performance ◽

High Performance Concrete ◽

Engineering Properties ◽

Mineral Admixtures ◽

Partial Substitution ◽

Construction Time ◽

Furnace Slag ◽

Durability Of Concrete

To meet demand of highperformance pavement concrete in highway, differentproportional concretes incorporating 30%—40% ground granulatedblast furnace slag and (or) fly ash were investigated on engineering properties in laboratory. Workability offresh concrete was evaluated by result of testing slump, mechanical property ofconcrete by flexural strength, abrasion resistance of concrete by index ofabrasion resistance and durability of concrete by chloride diffusioncoefficient and value of charge passed. The results indicate that measuredcharacteristics of concretes are superior to the relevant requisitions in specificationof highway. It was revealed that partial substitution ofmineral admixtures increased workability of fresh concrete, abrasion resistanceand durability of concrete. Addition of groundgranulated blast furnace slag is more favorable to flexural strength ofconcrete than that of fly ash, in particular for early-term to avoid delaying construction time with lower strength caused in use of greatvolume admixture.

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