MECHANICAL AND CHEMICAL ACTIVATION OF BLAST FURNACE SLAG AND ITS INFLUENCE ON THE MECHANICAL PROPERTIES OF THE RESULTING CEMENT PASTE

The usage of waste materials is a very important global topic. The large amount of waste everywhere in the world needs to be processed or disposed. Landfilling is not an option anymore, because of European legislation and restrictions. A lot of studies are trying to develop new options or possibilities of using waste materials. This research is trying to find a way to process blast furnace slag. A high-speed mill was used for the mechanical activation. Chemical activation was used as the next step of activation. There are many materials that could be used, but in this study we used slaked lime and water-glass. Slaked lime had a positive effect on mechanical properties. Samples had higher compressive strength but the effect was limited only for 5 wt. %. Another used material was water-glass, but in this case, there was a significant negative effect. Compressive strength and flexural strength were significantly reduced.

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Application areas of phosphogypsum in production of mineral binders and composites based on them: a review of research results

MATEC Web of Conferences ◽

10.1051/matecconf/201814901012 ◽

2018 ◽

Vol 149 ◽

pp. 01012 ◽

Cited By ~ 1

Author(s):

Leonid Dvorkin ◽

Nataliya Lushnikova ◽

Mohammed Sonebi

Keyword(s):

Mechanical Properties ◽

Blast Furnace ◽

Blast Furnace Slag ◽

Setting Time ◽

Industrial Wastes ◽

Cement Clinker ◽

Complete Replacement ◽

Slaked Lime ◽

The Impact ◽

Furnace Slag

The increase of the consumption of gypsum products in construction industry with a limited amount of natural gypsum deposits requires alternative sources of gypsum-containing raw materials. In some countries which have fertilizers industry plants, the problem can be solved using industrial wastes, e.g. phosphorgypsum – a byproduct of fertilizers’ production. Kept in dumps over decades, phosphorgypsum is subjected to the chemical changes due to washing out impurities with rain and other natural factors. However, there are observed deviations of harmful impurities in dumped PG depending on its age., Phosphorgypsum of any age requires chemical treatment to neutralize remains of phosphorus and sulfuric acids, fluorine compounds. According to our researches one of the most simple and effective method of neutralization the impurities is using lime-containing admixtures. The paper presents results of laboratory tests of phosphorgypsum as a component of clinker and non-clinker binders. There were investigated the impact of phosphorgypsum as admixture for clinker binders to substitute natural gypsum. Neutralized phosphorgypsum can be applied as mineralizing admixture in calcination of Portland cement clinker. Adding 2 to 2.5% of phosphorgypsum as setting time regulator resulted in a similar physical and mechanical properties compared to mix made with natural gypsum. Another important area of phosphorgypsum application is sulphate activatoion of low-clinker blast-furnace slag cement (clinker content is less than 19%). According to results, the incorporation of phosphorgypsum as sulphate activator in cement has the better effect as natural gypsum. Other development has been carried out to modify the phosphorgypsum binder properties. Complex additive consisted of polycarboxylate-based superplasticizer and slaked lime permitted an increase mechanical properties of hardened phosphorgypsum binder due to significant a reduction of water consumption. Such modified binder can be used as partial or complete replacement of gypsum binder for filling cements and finishing plasters. It can substitute gypsum in non-clinker binders like supersulphated cements. There were also developed compositions of supersulphated cements based on low-alumina blast furnace slag and phosphorgypsum. Supersulphated cements were tested in normal-weight and light-weight concrete.

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Pengaruh Penambahan RD 31 pada Beton dengan Substitusi Ground Granulated Blast Furnance Slag

RekaRacana: Jurnal Teknil Sipil ◽

10.26760/rekaracana.v6i3.191 ◽

2021 ◽

Vol 6 (3) ◽

pp. 191

Author(s):

Anni Susilowati ◽

Serin Ginting

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Blast Furnace ◽

Blast Furnace Slag ◽

Physical And Mechanical Properties ◽

Optimum Level ◽

Analysis Method ◽

Granulated Blast Furnace Slag ◽

Effect Regression ◽

Furnace Slag

ABSTRAKJauhnya lokasi batching plant dengan tempat penuangan kerapkali membuat beton setting sehingga dibutuhkan bahan tambah retarder. Ground Granulated Blast Furnace Slag (GGBFS) memiliki komposisi kimia mirip semen. Oleh karena itu, dilakukan penelitian penambahan retarder pada beton dengan substitusi GGBFS sebagai pengganti sebagian semen untuk mengetahui pengaruh (dengan uji regresi SPSS), sifat fisik dan mekanik beton, serta mendapatkan kadar optimum penambahan retarder. Metode penelitian ini menggunakan metode eksperimental dengan variasi campuran 90% semen, 10% GGBFS dengan retarder 0%, 0,2%, 0,4%, dan 0,6% berat semen dengan fas 0,5 sesuai SNI 03-2834-2000. Hasil penelitian menunjukkan retarder 0,2% - 0,6% mampu meningkatkan kuat tekan sebesar 19,61 - 50,59%. Berdasarkan hasil penelitian diperoleh kadar optimum 0,2% karena memiliki sifat paling baik.Kata kunci: GGBFS, kuat tekan, retarder ABSTRACTLong distance between batching plant to the pouring area often causes the concrete undergo a setting, so that a retarder addition material is needed. Ground Granulated Blast Furnace Slag (GGBFS) which has a chemical composition similar to cement. Therefore, a research was conducted on retarder addition to concrete with GGBFS substitution as a partial cement substitute to obtain the effect (regression analysis method in SPSS), physical and mechanical properties of concrete, and to obtain the optimum level of retarder addition. This research used an experimental method with a mixture variation of 90% cement, 10% GGBFS with retarder percentage as follows; 0%, 0.2%, 0.4%, and 0.6% of cement weight with a water/cement is 0.5 according to SNI 03-2834-2000. The results of research with the addition of a retarder of 0.2% - 0.6% were able to increase the compressive strength by 19.61 - 50.59%. Based on the results, the optimum level of retarder is at a variation of 0.2% as it has the best physical and mechanical properties.Keywords: GGBFS, compressive strength, retarder

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Mechanical properties and permeability of red mud-blast furnace slag-based geopolymer concrete

SN Applied Sciences ◽

10.1007/s42452-020-03985-4 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Xiangzhou Liang ◽

Yongsheng Ji

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Blast Furnace ◽

Red Mud ◽

Blast Furnace Slag ◽

Construction Materials ◽

Geopolymer Concrete ◽

Reaction Products ◽

Alumina Production ◽

Furnace Slag

AbstractRed mud, a by-product of alumina production, has a great impact on the environment due to its high alkalinity. In this paper, two-part geopolymer mortar was synthesized by combining red mud and blast furnace slag (BFS) to obtain optimized compressive strength and flexural strength for construction materials. Geopolymer concrete was prepared with the cementitious material in the concrete replaced by geopolymer mortar. Mechanical properties, permeability and microscopic properties of geopolymer concrete were measured. The results showed that the compressive strength grade of concrete prepared with geopolymer concrete can reach 54.43 MPa indicating that the geopolymer concrete can be used as materials for load-bearing members in structures. Due to lower total porosity and better pore structure, the permeability resistance of geopolymer concrete was significantly better than ordinary concrete. Microscopic analysis indicated that a large amount of aluminosilicate reaction products was generated in a geopolymer by the reaction of OH− with the aluminosilicate components in red mud and BFS in a strongly alkaline environment. The surface [SiO4]4− and [AlO4]4− tetrahedrons form chemical bonds through dehydroxylation, which is the direct reason for their high strength and determines their excellent physical and chemical properties.

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Effects of Short PAN Fiber Contents on Mechanical Properties of Metakaolin-Blast Furnace Slag Based Geopolymers

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.697.608 ◽

2016 ◽

Vol 697 ◽

pp. 608-611 ◽

Cited By ~ 1

Author(s):

Xin Chun Luo ◽

Chang An Wang

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Blast Furnace ◽

Blast Furnace Slag ◽

Pan Fiber ◽

Pull Out ◽

Fiber Bridging ◽

Work Of Fracture ◽

Furnace Slag ◽

Pan Fibers

This paper investigated mechanical properties and microstructure of metakaolin/slag based geopolymers reinforced by short polyacrylonitrile (PAN) fibers. The results showed that addition of short PAN fibers had no effect on the phase composition of the geopolymer but could strengthen and toughen the geopolymers remarkably. When the content of short PAN fibres was 0.8wt%, the geopolymers showed the highest compressive strength (99.84MPa) and flexural strength (13.76MPa). The addition of PAN fibers enlarged the work of fracture of the geopolymers and changed the fractural behavior from brittle to non-brittle fractural mode through fiber bridging and pull-out effects.

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The use of limestone sludge for the geopolymer preparation

IOP Conference Series Materials Science and Engineering ◽

10.1088/1757-899x/1205/1/012002 ◽

2021 ◽

Vol 1205 (1) ◽

pp. 012002

Author(s):

D Kubatova ◽

I Khongova ◽

M Krejci Kotlanova ◽

A Zezulova ◽

M Bohac

Keyword(s):

Compressive Strength ◽

Blast Furnace ◽

Linear Correlation ◽

Blast Furnace Slag ◽

Water Glass ◽

Setting Time ◽

Sludge Waste ◽

Alkaline Activator ◽

Positive Effect ◽

Furnace Slag

Abstract The study investigates the effect of sludge waste from mining and washing of limestone on the properties of geopolymer binders based on metakaolin and blast furnace slag. The effect of adding two types of limestone sludge on workability, setting time, compressive strengths, durability and pore distribution was investigated. Limestone sludge was dosed in an amount of 0–30 %. Sodium water glass was used as an alkaline activator in the ratio of 5:4. A linear correlation between the flowability and limestone sludge content was observed, and very satisfactory results of compressive strength after 90 days were obtained for samples with sodium water glass (about 55 MPa). The positive effect of CaCO3 on strength was confirmed. The increased content of clay components resulted in a reduction of compressive strength.

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Influence of Different Curing Days on Mechanical Properties of Concrete with Admixtures of Fly Ash, Blast Furnace Slag and Silica Fume

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.405-408.2843 ◽

2013 ◽

Vol 405-408 ◽

pp. 2843-2846

Author(s):

Jeong Eun Kim ◽

Wan Shin Park ◽

Sun Woong Kim ◽

Do Gyeum Kim ◽

Myung Sug Cho ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Compressive Strength ◽

Blast Furnace ◽

Fly Ash ◽

Silica Fume ◽

Blast Furnace Slag ◽

High Performance ◽

High Performance Concrete ◽

Furnace Slag

High performance concrete (HPC) can be made with cement alone or any combination of cement and mineral components, such as, blast furnace slag, fly ash, silica fume, kaolin, rice husk ash, and fillers, such as limestone powder [. In this study, three mixes of high performance concrete (HPC) with same water-binder ratio and different types of mineral admixtures were prepared. he compressive strength, splitting tensile strength and modulus of elasticity values were measured in accordance with the ASTM. The influence of fly ash (FA), blast furnace slag (BS) and silica fume (SF) on mechanical properties of HPC were compared and analyzed. Their mechanical properties are measured at 7 days and 28 days. The results showed that specimen BS45+SF5 performed better than specimens BS30+FA25+SF5 and BS65+SF5 for the compressive strength, splitting tensile strength and modulus of elasticity.

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Size Effect of High Performance Concrete with Blast Furnace Slag on Compressive Strength and Modulus of Elasticity

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.405-408.2820 ◽

2013 ◽

Vol 405-408 ◽

pp. 2820-2823 ◽

Cited By ~ 1

Author(s):

Wan Shin Park ◽

Jeong Eun Kim ◽

Nam Yong Eom ◽

Do Gyeum Kim ◽

Myung Sug Cho ◽

...

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Blast Furnace ◽

Size Effect ◽

Modulus Of Elasticity ◽

Blast Furnace Slag ◽

High Performance ◽

High Performance Concrete ◽

Standard Size ◽

Furnace Slag

The 100 x 200 mm cylinder specimens are standard size to measure the compressive strength and modulus of elasticity. However, it is not enough for experimental data of mechanical properties of HPC about size effect. The aim of this study is to investigate the size effect of high performance concrete (HPC) using blast furnace slag (BS) for mechanical properties such as, compressive strength and modulus of elasticity. Therefore, in this study, Type A (100 x 200 mm cylinder specimens) and Type B (150 x 300 cylinder specimens) were prepared. Blast furnace slag is used as a replacement for ordinary Portland cement (OPC). The compressive strength, modulus of elasticity of harden concrete were determined in the laboratory.

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Experimental Study on Mechanical Properties of High-Strength Concrete Using Blast Furnace Slag Fine Aggregate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.217-218.113 ◽

2011 ◽

Vol 217-218 ◽

pp. 113-118 ◽

Cited By ~ 1

Author(s):

Dong Sheng Shi ◽

Yoshihiro Masuda ◽

Young Ran Lee

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Blast Furnace ◽

High Strength Concrete ◽

Blast Furnace Slag ◽

High Strength ◽

Fine Aggregate ◽

River Sand ◽

Strength Concrete ◽

Furnace Slag

In this experiment, blast furnace slag fine aggregate that was produced by 3 different steel factory was been used in high-strength concrete, and mechanical properties of high-strength concrete were studied. The concrete using the blast furnace slag fine aggregate is admitted the increase of compressive strength as well as the case of the river sand when the water cement ratio is reduced, and the compressive strength can attain 100N/mm2. The strength of concrete using blast furnace slag fine aggregate is lower than the strength of concrete using natural river sand as fine aggregate, and the strength of concrete using mixture fine aggregate is middle of strength used river sand and strength used blast furnace slag fine aggregate. The crushing value of blast furnace slag fine aggregate is bigger than the natural river sand, and it could influence the strength of high-strength concrete using blast furnace slag fine aggregate.

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The Influence of the Properties of the Material Used for Obtaining Geopolymers on Their Structure and Compressive Strength

Revista de Chimie ◽

10.37358/rc.17.6.5638 ◽

2017 ◽

Vol 68 (6) ◽

pp. 1182-1187

Author(s):

Ilenuta Severin ◽

Maria Vlad

Keyword(s):

Compressive Strength ◽

Blast Furnace ◽

Wheat Straw ◽

Red Mud ◽

Blast Furnace Slag ◽

Complex Structure ◽

Point Of View ◽

Granulated Blast Furnace Slag ◽

Furnace Slag ◽

Straw Ash

This article presents the influence of the properties of the materials in the geopolymeric mixture, ground granulated blast furnace slag (GGBFS) + wheat straw ash (WSA) + uncalcined red mud (RMu), and ground granulated blast furnace slag + wheat straw ash + calcined red mud (RMc), over the microstructure and mechanical properties of the synthesised geopolymers. The activation solutions used were a NaOH solution with 8M concentration, and a solution realised from 50%wt NaOH and 50%wt Na2SiO3. The samples were analysed: from the microstructural point of view through SEM microscopy; the chemical composition was determined through EDX analysis; and the compressive strength tests was done for samples tested at 7 and 28 days, respectively. The SEM micrographies of the geopolymers have highlighted a complex structure and an variable compressive strength. Compressive strength varied from 24 MPa in the case of the same recipe obtained from 70% of GGBFS + 25% WSA +5% RMu, alkaline activated with NaOH 8M (7 days testing) to 85 MPa in the case of the recipe but replacing RMu with RMc with calcined red mud, alkaline activated with the 50%wt NaOH and 50%wt Na2SiO3 solution (28 days testing). This variation in the sense of the rise in compressive strength can be attributed to the difference in reactivity of the materials used in the recipes, the curing period, the geopolymers structure, and the presence of a lower or higher rate of pores, as well as the alkalinity and the nature of the activation solutions used.

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