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As a byproduct of steelmaking, steel slag occupies significant land resources and poses potential environmental and safety challenges due to its extensive accumulation. Recently, steel slag has shown promising applications in the field of concrete. However, considering the complexity of the plateau environment, the utilization of steel slag is relatively lacking, and its low reactivity and poor volume stability remain the main factors restricting its application in plateau concrete. This paper reviews the research status of steel slag activation techniques for concrete, including wet grinding, chemi-excitation, high-temperature activation, and carbonation treatment. The effects of different treatment techniques on the mechanical and durability properties of concrete and the potential issues are discussed. Although different modification methods can improve the activity and volume stability of steel slag to varying degrees, a single modification technology is difficult to achieve the high-quality utilization of steel slag in concrete on the plateau. Based on this, a steel slag grading grinding-magnetic separation utilization technique suitable for high-altitude areas is proposed, which is beneficial for improving the added value and utilization rate of steel slag in concrete. [ABSTRACT FROM AUTHOR]

In this paper, steel slag powder was used to replace part of the cement in road concrete, and group tests were carried out on coarse aggregates with different water–cement (W/C) ratios, different steel slag parameters, and different particle sizes. A sample of 100 mm × 100 mm × 100 mm was prepared and cured for 3 days, 7 days, and 28 days. In addition, the fluidity and compressive properties of the samples were also tested. The outcomes of this study revealed that, at a constant W/C ratio, increasing the proportion of steel slag improved the concrete's fluidity but reduced its compressive strength; the 3-day (3 d) compressive strength of 40% steel slag was lower because the early activity of steel slag was lower than that of cement; steel slag also decreased the early-hydration rate of concrete. Comparisons across different W/C ratios demonstrated that steel slag made a more significant contribution to lower W/C ratios than higher ones. The water requirement for steel slag was relatively moderate, and the compressive strength of steel slag concrete with a high W/C ratio notably improved in the later stages. Based on the experimental conditions, the optimal content of steel slag was found to be 35%. Reusing steel slag as a replacement for sand in coarse aggregate can effectively lower costs and offer an innovative approach to steel slag treatment. [ABSTRACT FROM AUTHOR]

The construction industry is looking for sustainable and cost-effective alternatives to conventional building materials. As the world faces increasing environmental challenges, the need for greener construction practices has become more urgent. Cement production is known for its high energy consumption and significant carbon dioxide emissions. Therefore, it is essential to find ways to reduce the environmental impact of cement production and use. One promising area of research is the use of industrial byproducts such as steel slag to partially replace cement in concrete. The use of these by-products not only solves the problem of waste disposal but also provides a sustainable solution to improve the properties of building materials. When mixed with cement, steel slag participates in pozzolanic reactions, in which reactive silica from the slag reacts with calcium hydroxide, produced during the hydration of cement, to form calcium silicate hydrate gel (CSH). This CSH gel is responsible for the strength and durability of concrete. Incorporating steel slag can improve the mechanical properties of concrete, including compressive, flexural, and tensile strength. In addition, steel slag can improve the durability properties of concrete, such as resistance to chemical attack, reduced permeability, and increased resistance to physical and chemical degradation over time. This paper investigates the durability properties of cement when partially replaced by steel slag, focusing on various aspects of durability, including resistance to chemical attack, mechanical strength, and long-term performance under various environmental conditions. The study includes a comprehensive experimental program designed to evaluate the impact of steel slag on the durability of concrete through a series of tests and analyses. [ABSTRACT FROM AUTHOR]

Steel slag is a product of industrial waste and such has been used as alternative aggregate materials in concrete production. Coconut fibre is readily available in tropical countries such as Nigeria. This paper focussed on using steel slag waste to replace granite at 10, 20, and 30% with the addition of coconut fibres of 40 mm average length added to the concrete at 0.3 and 0.6% of cement weight. Concrete samples of 40 MPa targeted strength were prepared with mix ratio of 1:1.3:2.2 and a water–cement ratio of 0.4, which were cured for 14, 28, 56, and 90 days and tested for impact strength, energy absorption from cracking, mechanical strengths, and durability. The impact resistance of the modified specimens was greater than the control specimens because the number of blows and potential energy needed to crack the slabs to cause ultimate destruction was higher in the modified concrete samples. The optimum compressive, split tensile strengths and sulphate attack were observed at 20% partial replacement of steel slag with granite at 0.3% coconut fibre binder weight which performed better than the control, indicating the durability of concrete infused with steel slag aggregate and natural fibres. [ABSTRACT FROM AUTHOR]

The release of steel slag into the environment has substantial repercussions, simultaneously affecting both the ecosystem and the economy. Therefore, the management and recovery of this waste demand careful consideration. In the context of the circular economy, this study aims to explore the feasibility of utilizing steel slag waste as a substitute aggregate for natural coarse and fine aggregates in the production of high-quality concrete. Throughout this research, concrete mixtures were developed by varying natural aggregate substitution rates with steel slag waste at 0, 25, 50, 75, and 100%. Comprehensive tests, encompassing physical, mineralogical, chemical, and mechanical analyses, were conducted on the steel slag waste to ascertain its primary technical properties. In all mixtures incorporating steel slag waste, compressive strength tests consistently revealed values surpassing those of the reference concrete. Notably, there were improvements of approximately 12% for coarse aggregate substitution and 32% for sand substitution. Assessments of flexural strength at 7 and 28 days underscored the substantial positive influence of fine and coarse aggregate substitution, especially at a 50% fine aggregate replacement, contributing significantly to enhanced flexural strength compared to conventional concrete. Furthermore, laboratory examinations indicated that the 28-day compressive and flexural strength, as well as water absorption of concrete, increased with slag content, albeit at the expense of reduced workability. Ultimately, the findings demonstrate the effective utilization of slag as a replacement for natural aggregates, maintaining the compressive and flexural strength of the concrete. [ABSTRACT FROM AUTHOR]

Steel slag (SS) is an industrial by-product, which is considered a potential material for replacing natural aggregates in concrete to limit the exploitation of natural resources and minimize the impact on the environment during the SS treatment. This study investigated the potential of re-using locally available SS as coarse aggregate in concrete and then evaluated the influence of different SS replacement levels for natural coarse aggregates on both fresh (i.e., workability and unit weight) and hardened properties (i.e., porosity, compressive strength, flexural strength, ultrasonic pulse velocity, surface electrical resistivity, water absorption, and dry shrinkage) of concrete. Experimental results show that replacing 40–100% (by volume) natural coarse aggregate with SS reduced workability and increased the unit weight of the fresh concrete mixture. Although the concrete porosity, water absorption, and drying shrinkage increased with increasing the SS content, the mechanical strength of the concrete was improved. Besides, the concrete samples containing SS exhibited an enhancement in surface electrical resistivity and their ultrasonic pulse velocity was comparable to that of the SS-free sample. The experimental results further demonstrated the high potential of utilizing SS as coarse aggregate in the production of concrete for sustainable development in construction.

The industrial development and growth in population activity caused an annual increase in solid wastes over the past decades. The emissions of CO2 from the cement industry are the main source of air pollution. Recycling wastes as cementitious materials conserve the ecosystem in different aspects, e.g., reduction of CO2 footprint. Consequently, the pozzolanic activity of two solid wastes abundantly available in Iraq, steel slag (SS) and waste glass (WG), were evaluated. This study aimed to replace them with ordinary Portland cement. This will achieve a sustainable, eco-efficient, and environmentally friendly construction industry. The Chemical analysis of the wastes by XRF and XRD suggests a possible cementitious capability owing to the amorphous nature of WG and the presence of C3S and C2S in SS. Accordingly, due to international standards, cubic mortars were produced by replacing cement with SS at 50% and WG at 50% and 20%. The effects of such replacements on the compressive strength of mortars were evaluated by comparison with that of the control mortars. WG increases workability and results in a higher strength index (72.8%) than that of SS (48.7%) at similar replacement levels (50%). Subsequently, SS and WG replaced coarse aggregates (CA) and cement, respectively, in concrete. The results revealed positive effects of SS on compressive strength in contrast to WG influence. The compressive strength of concrete cured for 91d increased by about 20% compared to the control sample upon incorporation of 50% SS without any WG.

Steel slag is an industrial by-product of steel production which is obtained during the pyrometallurgical process. Technological dissemination on effective utilization of steel slag in vast quantities globally is essential as the generation of steel is escalating year by year and the availability of steel slag is also in millions of tons. Though steel slag has been used for various applications, large quantities of steel slag have been utilized in the field of construction only. This review focuses on the recent advances on utilization of steel slag in construction sector and the impact of steel slag incorporation has been described in detail. Utilization of steel slag in construction industry as aggregate and cementitious material for the applications toward bricks production, asphalt mixes, radiation shielding concrete, foam concrete, self-compacting concrete, ceramic manufacturing, waterproof mortars and geopolymer composites fabrication has been discussed in detail. Steel slag will be an alternate source to conserve natural resources by utilizing large quantity of steel slag in construction industry. [ABSTRACT FROM AUTHOR]

The extensive accumulation of steel slag poses a severe threat to ecological environment. Utilizing steel slag in concrete effectively enhances the utilization rate. Under the coupling effect of low pressure and drying, the low activity problem restricts the application and development of steel slag in plateau concrete. This study focuses on the unique characteristics of plateau climate and comprehensively reviews the impact of steel slag on the frost resistance, salt erosion resistance, and shrinkage resistance of plateau concrete. Additionally, it analyzes the properties of steel slag and summarizes the challenges associated with using steel slag as an admixture and aggregate. Through a thorough analysis of existing research, we find that appropriate pretreatment of steel slag and the addition of suitable mineral admixtures can enhance the reactivity of steel slag, promote the development of more compact concrete structures, and improve the applicability of steel slag in plateau concrete. [ABSTRACT FROM AUTHOR]

The aim of this study is to compare the properties of refractory concrete made with thermally treated and untreated steel slag. Five concrete compositions were prepared and investigated in the present work. The first mixture, referred to as the reference, was formulated using dolomite aggregates, whereas the second and third mixtures were developed by replacing natural coarse aggregate with 50 and 100% by weight of thermally untreated steel slag, respectively. The same replacement ratio (50% and 100%) of thermally treated steel slag was used to produce the fourth and fifth mixtures. Specimens of each specimen were placed in a furnace and heated to 400 °C and 800 °C. The mass loss for all the specimens heated to 400 °C was about 8%, while the reference suffered the maximum mass loss at 800 °C, which was 21.6%. The mixture with a 100% substitution of thermally treated steel slag produced the maximum compressive strength when compared to other mixtures at a temperature of 800 °C. The compressive strength of the M5 mixture was 18 MPa versus 10.87 MPa for the reference mixture. Additionally, optical microscope examination of specimens containing thermally treated steel slag revealed less damage than that observed in mixtures with dolomite. [ABSTRACT FROM AUTHOR]

The impacts of steel slag (SS) and ground-granulated blast-furnace slag (GGBS) on the mechanical properties, hydration process, and microscopic characteristics of concrete were investigated in this study. The results show that substituting cement with SS has a negative impact on the strength; however, partial replacement of SS with GGBS could produce positive effect by facilitating the whole hydration of SS and cement. The improvement impact of GGBS on strength was small in early stages (3–28 days) and occurred mainly in the late stages (28–90 days). Meanwhile, the heat flow and cumulative hydration heat was decreased by the incorporation of SS and GGBS, in comparison to plain cement. The microscopic analysis results proved that replacing SS with GGBS could increase the whole hydration reaction degree, decrease the content of Ca(OH)2, enhance the compactness of the interfacial transition zone (ITZ), and refine the pore structure of concrete. Furthermore, a formula was established to estimate the splitting tensile strength according to compressive strength. The finding of this study provides valuable information on the practical application of the industrial wastes in concrete. [ABSTRACT FROM AUTHOR]

The innovation of structural forms and the increase in the energy-saving requirements of buildings have led to higher requirements regarding the application conditions of steel slag foam concrete (SSFC) to ensure that the SSFC has a lower thermal conductivity and sufficient compressive strength, which has become the primary research object. Through a comprehensive consideration of 7 d compressive strength and thermal conductivity, the recommend mix ratio of SSFC was as follows: maximum SS size = 1.18 mm, water–cement ratio = 0.45, replacement rate of SS = 20–30%. Moreover, a theoretical formula was derived to determine thermal conductivity versus porosity based on fractal theory. The measured values of the foam concrete found elsewhere corroborate the fractal relationship regarding thermal conductivity versus porosity. This fractal relationship offers a straightforward and scientifically sound way to forecast the thermal conductivity of SSFC. [ABSTRACT FROM AUTHOR]

Steel slag is a melted by-product that mainly consists of calcium carbonate and metal oxides generated in the process of steel manufacturing. The main objectives of this study are to evaluate the effectiveness of steel slags as fine and coarse aggregates in concrete and to determine the optimum quantity of steel slag as fine and coarse aggregates to enhance the strength of concrete. Concrete cubes were cast by mixing steel slag as replacement (i.e. 0%, 10%, 25%, 50%, 75% and 100%) for fine and coarse aggregate, separately. Abrasion test, sieve analysis, water absorption and specific gravity test were conducted to determine the properties of raw materials. Unit weight, workability, compressive strength, splitting tensile strength and the possibility of corrosion were experimentally evaluated to determine the effectiveness of steel slag. It is found that 75% steel slag mixed concrete indicates improvements in compressive strength, splitting tensile strength and unit weight, respectively. Further, it was noted that steel slag aggregates were not corroded after conducting the Accelerated Corrosion Test Method (ACTM). Therefore, the use of steel slag as fine and coarse aggregates for concrete would improve the mechanical properties of concrete and reduce the adverse environmental impact. [ABSTRACT FROM AUTHOR]

This paper investigates high‐strength concrete (HSC) exposed to high temperatures using the full replacement of natural aggregates with steel slag. Polypropylene (PP) and steel fibers are used as reinforcements, and the effects of calcium aluminate cement and ordinary cement on the mechanical properties of this concrete are compared. A total of 81 cylindrical specimens of 100 × 200 mm and 81 prism specimens of 100 × 100 × 350 mm were made using different amounts of cementitious materials (cement and silica fume) of 450, 500, and 550 kg/m3, with constant water‐to‐cementitious materials ratio of 0.28. The present results revealed that the HSC made with steel slag aggregates and calcium aluminate cement reinforced with steel fibers, had the greatest compressive strength of 84 and 50 MPa at temperatures of 20°C and 800°C, respectively; and flexural strength of 7.9 and 4.5 MPa, respectively, at the same temperatures. Similar HSC specimens constructed with ordinary cement, on the other hand, performed better at 400°C. Moreover, the flexural strength of the samples placed at temperatures of 400°C and 800°C decreased by 28% and 48%, respectively, compared to the specimens at 20°C. Compared to specimens comprised of polypropylene fibers, the fracture energy and displacement of HSC with steel slag reinforced with steel fibers subjected to high temperatures were increased by approximately 100% and 60%, respectively. [ABSTRACT FROM AUTHOR]

Copyright of Inorganic Chemicals Industry is the property of Editorial Office of Inorganic Chemicals Industry and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Reusing industrial solid waste in cement‐based products is an economical and environmentally friendly solution. This study investigated the effect of steel slag on the mechanical properties of concrete mixtures, and development of damage constitutive relationship of steel slag concrete (SSC). Two steel slag aggregates, including fine steel slag aggregate (SSAF) and coarse steel slag aggregate (SSAC) were incorporated into the concrete mixtures to SSC. The portions of natural sand and coarse aggregate each were replaced with SSAF and SSAC at 10%–100% (interval of 20%) by weight. Therefore, effects of SSAF and SSAC on the mechanical properties of SSC mixtures were evaluated separately. Moreover, damage model of SSC mixtures was developed based on Lemaitre's equivalent strain principle and Weibull probability density function. The damage constitutive model was revised using the functional relationship between the toughness index, brittleness index, and distribution parameters. The results indicate that SSC's mechanical properties, crack resistance, and toughness have been significantly improved with increased steel slag content. However, reduction in strength was observed in the SSC specimens containing steel slag above 50% replacement. Nevertheless, these strengths are higher than that of normal concrete. The modified damage constitutive relationship fits better with the experimental results. [ABSTRACT FROM AUTHOR]

This study focuses on the workability and compressive strength of ceramsite self-compacting concrete with fine aggregate partially substituted by steel slag sand (CSLSCC) to prevent the pollution of steel slag in the environment. The SF, J-ring, visual stability index, and sieve analysis tests are primarily employed in this research to investigate the workability of freshly mixed self-compacting concrete containing steel slag at various steel slag sand replacement rates. The experiment results indicate that CSLSCC with the 20% volume percentage of steel slag (VPS) performs better workability, higher strength, and higher specific strength. The 7-day compressive strength of CSLSCC with the 0.4 of the water-binder ratio (W/B), decreases with the increase of steel slag content, while the 28-day compressive strength increases significantly. The ceramsite self-compacting concrete with good comprehensive performance can be obtained when the substitution rate of steel slag sand for fine aggregate is less than 20% (volume percentage). [ABSTRACT FROM AUTHOR]

Copyright of Fly Ash Comprehensive Utilization is the property of Hebei Fly Ash Comprehensive Utilization Magazine Co., Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The disposal of steel slag leads to the occupation of large land areas, along with many environmental consequences, due to the release of poisonous substances into the water and soil. The use of steel slag in concrete as a sand-replacement material can assist in reducing its impacts on the environment and can be an alternative source of fine aggregates. This is the very first paper that seeks to experimentally investigate the cumulative effect of steel slag and polypropylene fibers, particularly on the impact resistance of concrete. Various concrete mixes were devised by substituting natural sand with steel slag at volumetric replacement ratios of 0%, 10%, 20%, 30%, and 40%, with and without fibers. Polypropylene fibers of 12 mm length were introduced into the steel slag concrete at 0%, 0.5%, and 1.0% by weight of cement as a reinforcing material. Performance evaluation of each mix through extensive experimental testing indicated that the use of steel slag as partial substitution of natural sand, up to a certain optimum replacement level of 30%, considerably improved the compressive strength, flexural strength, and tensile strength of the concrete by 20.4%, 23.8%, and 17.0%, respectively. Furthermore, the addition of polypropylene fibers to the steel slag concrete played a beneficial role in the improvement of strength characteristics, particularly the flexural strength and final drop weight impact energy, which had a maximum rise of 48.1% and 164%, correspondingly. Moreover, integral structure and analytical analyses have also been performed in this study to validate the experimental findings. The results obtained encourage the use of fiber-reinforced steel slag concrete (FRSLC) as a potential impact-resistant material considering the environmental advantages, with the suggested substitution, of an addition ratio of 30% and 1.0% for steel slag and polypropylene fibers, respectively. [ABSTRACT FROM AUTHOR]

Iron tailing solid waste not only has a high annual output but also has a low comprehensive utilization rate. Low utilization rate of iron tailings seriously restricts the development of comprehensive utilization of solid waste. In order to prepare an iron tailings-based ternary solid waste admixture and to verify its application to concrete, first, the effect of solid waste synergy on the strength of an iron tailings-steel slag-desulfurization ash admixture (ISD) system was investigated. Second, the effect of chemical activator dosing on the strength of an ISD system was studied and the mechanism of chemical activator action on the ISD system was investigated by thermogravimetric analysis (TG-DTA) Then, the effect of this admixture on the strength of concrete was studied. Finally, the mechanism of the effect of this admixture on the strength of concrete was clarified by mercury intrusion porosimetry (MIP) and backscattering electron tests (BSE). The results showed that the 7 d and 28 d compressive strengths of the ISD admixture were significantly higher than those of iron tailings single admixture. The 7 d and 28 d compressive strengths of the ISD system reached 24.9 MPa and 36.1 Mpa, respectively, when the ratio of iron tailings:steel slag:desulfurization ash = 1:1:1. Na2SiO3 is suitable for the early strength agent of the ISD admixture, but the amount of admixture should not exceed 0.6% of the admixture. TG-DTA shows that Na2SiO3 is enhancing the early strength of the ISD system by promoting the consumption of Ca(OH)2 in the ISD system to produce C-S-H. However, in the late reaction of the ISD system, Na2SiO3 inhibits the late strength development of the ISD system by suppressing Ca(OH)2 production. Concrete with ISD dosing of 30% or less meets the C40 requirement. MIP and BSE show that ISD provides a filling effect to concrete, but also causes a reduction in the active reactants of concrete and the combined effect of microfilling and active effects affects the strength development of ISD concrete. This study provides a theoretical and scientific basis for the preparation of iron tailings-based ternary solid waste dopants, and, in addition, the study promotes the consumption of iron tailings solid waste and the development of multiple solid waste dopants. [ABSTRACT FROM AUTHOR]

Cement is the most commonly used construction material. Now, cement production is increasing rapidly. In order to minimize the production and usage of cement, an alternative solution is to be implemented as either or partial replacement of cement. GGBS is the waste byproduct produced during the manufacturing of Steel. GGBS is used as a replacement for cement for every 5% and the optimum mix is found out by studying the mechanical properties. Replacement of GGBS was carried out up to 50% against cement. The presence of GGBS in the concrete mix exhibits notable achievement in the compressive strength of the concrete, however the presence of GGBS reduces the performance of concrete in split tensile stress and flexural stress due to increase in brittleness of the material. Modulus of elasticity of GGBS concrete shows prominent performance when compared with conventional concrete. From the above mixes, GGBS with 45% replacement against cement in concrete shows a better performance. [ABSTRACT FROM AUTHOR]

The characteristics of ingredients used for performing construction will affect the performance of prepared concrete. Aggregates are major constituents of concrete and it has been observed by researchers that characteristics of material used as aggregate significantly influence the strength and workability of concrete. Here, in the present work effect of flaky aggregates and steel slag as partial replacement of coarse aggregate on the characteristics of concrete composed by replacing cement by sand has been investigated. Two types of mixes have been prepared by varying the ratio of sand and marble powder which is 1:1 and 1:0.5, coarse aggregates are partially replaced by flaky aggregate and steel slag in 10%, 15%, 20%, 25% and 30% by weight. It has been observed that increase in proportion of flaky aggregate reduces the strength and workability of concrete and increase in steel slag increases the strength of concrete but reduces the workability. Mixing both the materials simultaneously increases the early strength of concrete and then lowers the percentage increase of strength, however, produces the concrete with low workability. [ABSTRACT FROM AUTHOR]

• Steel slag as aggregate in concrete for high temperature TES. • Concrete mixtures thermally cycled from 290 to 700 °C. • OPC and CAC with steel slag preserve integrity after thermal cycling. • Concrete with steel slag revealed promising specific heat capacity. • Thermal conductivity and compressive strength need further improvement. Thermal energy storage represents a crucial element to increase solar power dispatchability. Within sensible heat storage in solid media, concrete is considered a low-cost alternative to be further developed and therefore, this has been addressed in this paper. Four concrete dosages were designed, combining each type of considered cement, ordinary Portland and calcium aluminate cement, with each type of considered aggregate, silico-calcareous and a steel slag. Thermo-mechanical properties of concrete were studied before and after 10 thermal cycles from 290 °C to 700 °C. Maximum operating temperature and heating rates were selected accordingly to the targeted application, a concentrating solar power (CSP) tower plant. At macro-level, results show thermal cycle stability of concrete with steel slag aggregate in both cement types. On the contrary, at micro-level, the petrography analysis shows the lack of bonding between steel slag aggregate and the cement paste. In contrast, concrete mixtures containing silico-calcareous aggregates collapse after thermal cycling. [ABSTRACT FROM AUTHOR]

In the present investigation, induction furnace (IF) steel slag as coarse aggregate with 0%, 20% and 40% replaced concrete specimens of size 150 × 150 × 150 mm was prepared as an initiative to utilize iron-rich IF steel slag. The casted concrete specimens were cured for 28 days at room temperature (28 °C) in freshwater, and the obtained compressive strength is 22.5, 24.0 and 29.2 N/mm2, respectively. The blocks were then immersed in seawater under laboratory condition for 28 days, and variation in pH was monitored at regular intervals. The composition and mineralogical phases [quartz (SiO2), iscorite (Fe7SiO10), hematite (ε-Fe2O3) and almandine (Fe3Al2Si3O10)] present in IF steel slag were identified using XRF and XRD analysis, respectively. Surface morphology and elemental composition were studied using FESEM with EDAX analysis for before and after immersion of concrete blocks in seawater. Structural bonding of concrete blocks before and after immersion was studied using FTIR analysis. Compressive strength of concrete specimens after the immersion in seawater was evaluated and compared with before immersion in seawater. This initiative will be a major support for induction furnace steel industries via economic benefits. Utilization of iron-rich IF steel slag in marine concrete can be a vital candidate for the betterment of marine ecosystem via primary production of marine resources. [ABSTRACT FROM AUTHOR]

Concrete is as a significant building material. Due to the fact that it is possible to incorporate by-products and industry waste into its structure, concrete represents an important sustainable material. Steel slag has a great potential for its reuse in concrete production. Despite that it is subject to volume changes over time, it can be used in concrete as a cement replacement or as a substitute for natural aggregates. The paper is focused at investigation the concretes with steel slag as a substitute of natural gravel aggregate of 4/8 mm and 8/16 mm fractions. In addition, a life cycle assessment within the system boundaries cradle-to-gate was performed. Results showed that some samples with slag have better mechanical parameters than samples with natural aggregate and significantly affect the utilization rate of non-renewable raw materials and reduce the overall negative environmental impacts of concrete up to 7 %.

This study systematically investigated the influence of varying carbon dioxide (CO 2) dosages and steel slag (SS) replacement rates on the fresh and hardened properties of concrete through the injection of CO 2 gas during the mixing process. The composition of hydration products, degree of hydration, and the evolution of microstructural characteristics within the CO 2 -SS-cement system were analyzed. The results showed that CO 2 addition during the mixing process enhanced early strength in SS concrete. For concrete with a 10 wt% SS replacement rate, the incorporation of CO 2 ranging from 0.4 wt% to 1.2 wt% of the total mass of cementitious materials resulted in notable compressive strength increases of 1.26%–12.47%, 0.64%–6.14%, and 11.79%–18.24% at ages of 1 d, 3 d, and 7 d, respectively. CO 2 rapidly reacted with SS to form calcite-type CaCO 3 and promoted the generation of C-S-H through synergistic hydration with cement. However, a high CO 2 dosage (1.2 wt%) led to issues such as microcrack propagation and interface loosening due to CaCO 3 deposition, which could be mitigated to some extent by appropriately increasing the SS content. • CO 2 -mixing and steel slag synergistically improve early strength of concrete. • Increasing steel slag content alleviates adverse effects of high CO 2 dosage. • CO 2 -mixing enhanced the early cement hydration. [ABSTRACT FROM AUTHOR]

This study investigated the effectiveness of tartaric acid treatment in inhibiting the expansive behaviour of basic oxygen furnace (BOF) steel slag, aiming to optimize its utilization as a sustainable replacement for natural coarse aggregate in concrete. Tartaric acid-treated steel slag (TTSS) and non-tartaric acid-treated steel slag (NTSS) were comprehensively characterized for particle size and shape properties, physical and mechanical behaviour, and durability aspects including MgO stability factor and iron unsoundness. Chemical, morphological, mineralogical, and microstructural analyses were conducted using XRF, SEM-EDS, XRD, FT-IR, and optical microscopy, elucidating the impact of tartaric acid treatment. Compressive strength tests were then performed with TTSS incorporation levels of 30 %, 40 %, 50 %, and 0 % as reference batch (RB). As a result, TTSS showed 7.44 % and 10.92 % better physical and mechanical properties than NTSS respectively. Whereas on durability aspects, TTSS depicts 40 % better results on iron unsoundness and 36.43 % higher water absorption over NTSS. Furthermore, a maximum compressive strength of 44 MPa was achieved with a significant improvement of 15.80 % from RB. Additionally, TTSS aggregate-based cement concrete exhibited a denser microstructure and improved performance. This work highlights the potential of BOF steel slag as an aggregate resource, contributing to a circular economy and mitigating the environmental burdens associated with traditional aggregate production. [Display omitted] • Treated steel slag aggregate significantly improves the volumetric stability. • Steel slag tartaric treatment showed better or comparable key aggregate properties. • Achieved 50 % replacement of conventional aggregate with the treated aggregate. • Sustainable and eco-friendly approach towards steel slag solid waste management. [ABSTRACT FROM AUTHOR]

This study developed a sustainable concrete incorporating high-volume steel slag waste for the large-scale road construction project in Vietnam. The engineering performance, microstructure and sustainability of concrete mix were characterised using X-ray diffraction, Fourier transform infrared, Scanning electron microscopy / Energy dispersive spectroscopy, together with life cycle and cost assessment. The findings indicated that the slag-enriched concrete can achieve comparable strengths with traditional concrete over curing age. The presence of steel slag particles facilitates hydration precipitation of C-S-H and ettringite. Regarding sustainability, using high-volume steel slag concrete for 1 m3 functional unit exhibits a significant reduction of total energy consumption (18.5%), global warming impact (GWI) (22.3%), and total cost (28.7%), compared to the traditional concrete. Translating into the project scale of 2000 m3 of concrete, these benefits can turn into a significant energy savings (555,180 MJ), lower total GWI emissions (119,180 kg CO 2-eq) and reduced total costs (US$27,660). This research outcomes showcased the practical application of high-volume steel slag clinkerless concrete for future sustainability in construction. [Display omitted] • SS waste as SCM and aggregate alternative was utilised up to 60% by mass of concrete. • SS accelerates the formation of hydration products (esp. ettringite) and offers pore-filling effects. • High Ca/Si and Ca/(Si+Al) and Al/Si ratios are found in cement matrix incorporating SS. • For 1 m3 unit, FS-SA reduced energy consumption (18.5%), GWI (22.3%), and cost (28.7%). • This project achieves energy savings (555,180 MJ), lower GWI (119,180 kg CO 2-eq) and reduced cost (US$27,660). [ABSTRACT FROM AUTHOR]

This research tests energy optimised furnace (EOF) steel slag as substitution for natural coarse aggregate in concrete. Steel slag's usefulness as a substitute for natural coarse aggregate in concrete is the primary goal of this research. According to IS:2386-1963, the characterization of EOF steel slag, as coarse, is done by examining the shape and size of a particle, mechanical properties, physical properties, soundness, and alkali-aggregate reactivity. Tests for detection of staining material in steel slag and hardness of inter-facial transition zone in hardened cement paste were also carried out. The chemical analysis of the steel slag reveals the stability of oxides present in the steel slag. Microstructural characterization by SEM (scanning electron microscope) analysis of steel slag aggregate was also employed to support the characterization and XRD analysis, and it was found that the EOF steel slag is crystalline. The digital image processing technique (DIP) is adopted to study the shape indices, circularity, sphericity, shape factor, and roundness of natural and EOF steel slag aggregate. According to the characterization and strength investigation, steel slag aggregate outperforms natural coarse aggregate. [ABSTRACT FROM AUTHOR]

Copyright of Engineering Mechanics / Gongcheng Lixue is the property of Engineering Mechanics Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aiming at the problem of disposal and resource utilization of steel slag, the research on the application of steel slag concrete in armor block for sea embankment project was carried out. Taking Baosteel drum slag as an example, the mix proportion of steel slag concrete was designed based on the performance analysis of steel slag, and the influence of different contents of steel slag on the properties of concrete was investigated. The results indicate that with the portion of steel slag increasing, concrete slump decreases gradually; compressive strength, impermeability grade, and abrasion index increase; electric flux and diffusion coefficient increase slightly. In the pilot project, steel slag concrete was used to precast the armor block in sea embankment project. The structural strength meets the design requirements and the cost is more economical. It is found that the appearance of steel slag concrete component is slightly different from that of ordinary one in the offshore environment during usage period, and there is no obvious difference in service performance, which provides a new way for disposal and utilization of steel slag in coastal areas. [ABSTRACT FROM AUTHOR]

In this study, we aimed to investigate the effect of artificial reefs (ARs) made from concrete, steel, and steel slag on the concentrations of As, Cd, Cr6+, Cu, Hg, Ni, Pb, and Zn in marine ecosystems. We conducted a field investigation of the concentration of heavy metals (HMs) in seawater and marine organisms in the East Sea, South Korea and complemented it with an indoor elution experiment. The concentrations of the eight HMs in the field investigation and elution experiment satisfied the environmental standards. In the elution experiment, elution of Cr6+ from the concrete models was confirmed; however, it may be insignificant in marine ecosystems. These results revealed that the effect of ARs made from concrete, steel, and steel slag on the concentration of HMs in the marine environment was insignificant.

Steel slag (SS) is rarely used as a sole binder in wet-cast concrete production, which, however, is successfully realized in this study through early-age ambient-pressure carbonation activation without cement involvement. Standard mechanical, performance-based, and microstructural investigation methods including compressive strength test, sulfate attack test, thermogravimetric analysis (TGA), mercury instruction porosimetery (MIP), etc., were adopted to verify the performance of the product. First, the cement-free wet-cast SS concrete presented comparable carbon sequestration capacity as OPC concrete. Second, the superior strength gain was verified on full-scale concrete products, and carbonation-activated wet-cast SS concrete pipes demonstrated improved performance, attributed to the high carbonation degree for SS and the densified microstructure. Last, the environmental and economic assessments confirm that 100 % substitution of cement with SS can significantly reduce CO 2 emissions, energy consumption, and total cost for carbonation-activated wet-cast SS concrete, which contributes to both environmental protection and sustainable development in the construction industry. [Display omitted] [ABSTRACT FROM AUTHOR]

The present research investigated the influence of steel slag (SS) with variable particle size on the workability and mechanical properties of concrete. Different SS size ranges (0-15 μm, 15-30 μm, 30-45 μm and 45-80 μm) were obtained by sieving and then were characterised by a laser particle size analyser and a scanning electron microscope (SEM). The slump, compressive strength, pore structures and thermal analysis were used to evaluate the effect of the SS particle size on cement and concrete properties. The experimental results showed that finer SS (0-15 μm and 15-30 μm) resulted in negative effects on the workability, while 30-45 μm and 45-80 μm SS particles presented completely opposite results. Both of these effects were more apparent as the steel slag replacement ratio was increased up to 30 wt.%. Concrete samples with 0-15 μm and 45-80 μm SS particles presented comparable 7- and 28-day compressive strength to the control concrete when their replacement ratios were less than 10 wt.%. Moreover, the concrete samples with 45-80 μm SS particles at 5% dosage developed the highest compressive strengths at 7 and 28 days, which were 2% and 5% higher than the control sample, respectively. The pore structure results indicated that a composition of 5% 45-80 μm SS particles was advantageous for refining the pore structures of cement paste, further contributing to the 28-day compressive strength development of concrete.

Iron tailing solid waste not only has a high annual output but also has a low comprehensive utilization rate. Low utilization rate of iron tailings seriously restricts the development of comprehensive utilization of solid waste. In order to prepare an iron tailings-based ternary solid waste admixture and to verify its application to concrete, first, the effect of solid waste synergy on the strength of an iron tailings-steel slag-desulfurization ash admixture (ISD) system was investigated. Second, the effect of chemical activator dosing on the strength of an ISD system was studied and the mechanism of chemical activator action on the ISD system was investigated by thermogravimetric analysis (TG-DTA) Then, the effect of this admixture on the strength of concrete was studied. Finally, the mechanism of the effect of this admixture on the strength of concrete was clarified by mercury intrusion porosimetry (MIP) and backscattering electron tests (BSE). The results showed that the 7 d and 28 d compressive strengths of the ISD admixture were significantly higher than those of iron tailings single admixture. The 7 d and 28 d compressive strengths of the ISD system reached 24.9 MPa and 36.1 Mpa, respectively, when the ratio of iron tailings:steel slag:desulfurization ash = 1:1:1. Na2SiO3 is suitable for the early strength agent of the ISD admixture, but the amount of admixture should not exceed 0.6% of the admixture. TG-DTA shows that Na2SiO3 is enhancing the early strength of the ISD system by promoting the consumption of Ca(OH)2 in the ISD system to produce C-S-H. However, in the late reaction of the ISD system, Na2SiO3 inhibits the late strength development of the ISD system by suppressing Ca(OH)2 production. Concrete with ISD dosing of 30% or less meets the C40 requirement. MIP and BSE show that ISD provides a filling effect to concrete, but also causes a reduction in the active reactants of concrete and the combined effect of microfilling and active effects affects the strength development of ISD concrete. This study provides a theoretical and scientific basis for the preparation of iron tailings-based ternary solid waste dopants, and, in addition, the study promotes the consumption of iron tailings solid waste and the development of multiple solid waste dopants.

Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Industrial development has generated enormous conveniences for humans at the cost of environmental pollution. Cement production is a major cause of carbon dioxide emission in the construction industry, and utilization of a large number of aggregates in concrete is causing scarcity of natural resources and irreversible depletion. The practice of utilizing industrial wastes in the production of concrete can be a useful solution. In this research, green concrete of enhanced properties is produced by incorporation of milled glass as partial replacement of cement, and fine aggregates are replaced by granular steel slag with different dosages. Ten types of concrete mixes substituting 10%, 20%, and 30% of cement by glass powder (GP) and 40%, 60%, and 80% of sand by granular steel slag (SS) were assessed in terms of rheological, mechanical, and microstructural properties. Results indicated that concrete having 80% granular steel slag and 20% glass powder shows a maximum increase of 42%, 16%, 16%, and 14% in splitting tensile strength, flexural strength, modulus of elasticity, and compressive strength, respectively. Scanning electron microscopy depicts the formation of secondary calcium silicate hydrate (CSH) and improved packing density in concrete mixes having granular steel slag and glass powder. Thus, granular steel slag and glass powder can effectively be used as cement and sand replacement in the production of value-added green economical concrete, reducing environmental pollution. [ABSTRACT FROM AUTHOR]

This study investigated the significance of steel slag concrete created with varying water cement ratios. Steel slag from Prism Nigeria Limited was used to replace granite (at 0, 40, 50 and 60 %) in concrete. Properties of this modified concrete were examined and its results were exposed to measurable test utilizing Analysis of Variance (ANOVA). The outcome indicated that the compressive and flexural qualities of the concrete increased with increased in slag content but consistently decreased as the watercement ratios increased. The p-values of the ANOVA test for the models term are significant because they are less than 0.05. [ABSTRACT FROM AUTHOR]

A continuous increase in demand for natural resources, in a high proportion for the construction sector, creates the necessity to search for alternatives. This work is intended to do so and the aim is the replacement of natural aggregates in some concrete samples with a metallurgical industry by-product. The replacement was gradual and only for one type of the three dimensions utilized. The results of the many tests conducted revealed the possibility of natural aggregate replacement in some extent, keeping the resulted properties of samples within the limits of the standards.

Steel slag is one of the results of the rest of smelting iron ore/ steel. To reduce the abundance of steel slag, this study seeks to examine utilization as a substitute for gravel in the concrete used for construction sabodam.The durability of concrete on the outer layer was analyzed by using the results of several studies related.The most influential factor is the compressive strength of bump (impact) as a representation of the clash due to lava rock.It will be discussed about the potential use and durability. To analyze the stability of the sabodam, researcher use SNI 2851: 2015 about Sediment Retention Building Design. The parameter used is the stability of the tilting, sliding and bearing capacity. For alternative use sabodams core material, researcher used split stones and steel slagconcrete. The flood scenarios can be divided into two, namely flood plain and flood lava. Based on the results obtained, the potential for instability is found in the parameters of carrying capacity. Thesabodamwhich using split stones, the bearing capacity of the land has a minimum strength is worth -0.98 kN/m2 (for flood) and -0.43 kN/m2 (for lava flood), while sabodam with steel slag has a minimum strength of 1.74 kN/m2 (for flood) and 1.57kN/m2 (for lava flood) which means notensile stresses occured. The conclusion is the concrete with steel slag can be used as material for sabodam.

The mechanical behaviors of the self‐stressing steel slag aggregate concrete filled steel tubular (SSSACFST) stub column are investigated for practical structural applications. Twelve specimens under axial and eccentric compression are tested. The influences of different parameters, such as the eccentricity, the diameter–thickness ratio of the steel tube and the expansion rate of the steel slag aggregate concrete (SSAC) are studied. The experimental results show that the shear and the bending deformation dominate the failures of the specimens under axial and eccentric compression, respectively. The column with a high diameter–thickness ratio has a low ultimate bearing capacity and ultimate strain. The incremental range of the load capacity and the ultimate axial and circumferential strains of the specimens will be increased by raising the expansion rate of the SSAC. Based on the experimental results, the applicability of the current concrete filled steel tube design provisions for the SSSACFST stub columns is evaluated, and two analytical models for predicting the bearing capacity of the SSSACSFT stub columns under axial and eccentric compression are proposed. [ABSTRACT FROM AUTHOR]

A continuous increase in demand for natural resources, in a high proportion for the construction sector, creates the necessity to search for alternatives. This work is intended to do so and the aim is the replacement of natural aggregates in some concrete samples with a metallurgical industry by-product. The replacement was gradual and only for one type of the three dimensions utilized. The results of the many tests conducted revealed the possibility of natural aggregate replacement in some extent, keeping the resulted properties of samples within the limits of the standards. [ABSTRACT FROM AUTHOR]

To overcome the scarcity of natural resources as construction material and to reduce the hazards from industries, industrial wastes can play a very significant role. In this paper, the influence of glass powder and steel slag is reviewed. It is concluded that glass powder and steel slag can upset some portion of concrete thereby providing significant improvement in mechanical properties of concrete consequently reducing the environmental hazards from industries.

Blast furnace /steel slag-based geopolymer and recycled aggregate (RA) as green alternatives to cement and natural aggregate (NA), respectively, are attracting increasing attention. This study investigated the influence of four different aggregate systems (i.e., full-NA, full-recycled coarse aggregate, full-recycled fine aggregate, and full-RA) and three different replacement ratios of steel slag (i.e., 0%, 25%, and 50% of the precursor) on the mechanical properties (compressive and splitting tensile strength) and fracture properties (fracture energy and fracture toughness) of one-part slag/steel slag-based geopolymer concrete, aiming to promote its utilization in structural engineering. The experimental results indicate that substituting ordinary Portland cement with slag-based one-part geopolymer significantly enhanced the compressive and splitting tensile strength of geopolymer natural aggregate concrete (GNAC), although it leaded to a decrease in fracture properties. The incorporation of RA in GNAC resulted in deteriorated properties, with the 28-day compressive strength being reduced by up to 5%− 19.4% and fracture energy being reduced by up to 16.8%− 43.8%. Moreover, incorporating an appropriate amount of steel slag (approximately 25%) in geopolymer fully recycled aggregate concrete (GFRAC) had minimal impact on mechanical properties, while it enhanced the fracture energy values by up to approximately 16.6%. Nevertheless, a higher content of steel slag adversely affected the relevant properties due to its lower cementitious activity compared to slag. To mitigate the drawbacks associated with steel slag, less than 25% of steel slag content is recommended considering the mechanical and fracture properties of GFRAC. • 100% RCA and RFA were adopted to prepare GFRAC with slag/steel slag. • Effects of RA and steel slag on the mechanical and fracture properties were studied. • DIC was used to monitor the crack growth behavior of GFRAC. • The fracture surface feature of GFRAC were explored by SEM. [ABSTRACT FROM AUTHOR]

Recycling steel slag (SS) and waste glass (WG) in concrete represents a sustainability measure to promote the production of cost-effective and eco-friendly concrete. This study assessed the weight replacement effects of steel slag (SS) with coarse aggregate (up to 100 %), those of waste glass (WG) with cement (up to 30 %), and the water-to-binder ratio on the workability, density, compressive strength, and splitting strength. Multiple blends of the binary binders were examined using the design of experiments (DoE) approach to evaluate the technical feasibility of SS and WG and their synergistic effects in enhancing the properties considered. The second-order polynomial model used was sufficiently accurate to yield high correlation levels between the responses and the studied variables with high determination coefficient up to 98 %. The inclusion of WG in concrete produced with a 100 % replacement level of SS effectively addressed the site rheological pumping problems with higher strength, 58 % more in compressive and 33 % more in splitting strengths. • Steel slag coarse aggregate (SS) and waste glass powder (WG) were recycled into sustainable concrete. • Multiple blends of binary binders were examined using the design-of-experiments approach • The complementary role of SS and WG on the concrete mechanical strengths was modelled • The proficiency of the models was verified through statistical methods. • The inclusion of WG in concrete made with 100 % SS satisfied the workability requirements. [ABSTRACT FROM AUTHOR]