Advances in the Analysis of Properties Behaviour of Cement-Based Grouts with High Substitution of Cement with Blast Furnace Slags

This article presents a study of the main properties (consistency, workability, leaching, unsoundness, and mechanical properties) of cement grouts prepared with cement replacement by blast furnace slag (GGBS). Mixtures have been analyzed in the absence of additives and reached high replacement percentages. As shown in the different tests presented, the observed evolution of the resistance and workability of the mixtures makes them very interesting for its application. Different types of cement (CEM-I 42.5 and CEM-I 52.5 R) and different water/binder values (1 and 0.67) are used. The results present opportunities for the steel industry by the intensive valorization of slag waste. The reduction of the use of cement in construction is also one of the key aims of this line of research. Results show improvements in the mechanical response with good fresh state properties for substitution percentages up to 70%. It is verified with leaching analysis that these products have less impact on the environmen

Development in Sustainable Concrete with the Replacement of Fume Dust and Slag from the Steel Industry

Nowadays, the reuse of waste is a challenge that every country in the world is facing in order to preserve the planet and introduce a circular economy. The chemical composition of some steel waste suggests that there are potentially appropriate substances for reuse, since this type of slag undergoes a process similar to that of cement in its manufacture. The advantages for the environment are obvious, as it valorises waste that is deposited in landfills. This paper studies the field of stainless steel, because its composition is different from that of carbon steel, and the replacement of cement with material or waste produced in the manufacture of stainless steel in a concrete matrix. This paper presents the results of replacing 25% of cement with material or waste produced in the manufacture of stainless steel in a concrete matrix whose values in the substitutions carried out were around 21% and 25% in terms of increased resistance capacity. These results have been obtained by carrying out tests, in terms of both strength and environmental capacity, allowing us to determine viable applications for the use of steel waste to improve the performance of cement or at least match it

Study of the Suitability of Different Types of Slag and Its Influence on the Quality of Green Grouts Obtained by Partial Replacement of Cement

This paper is part of a research line focused on the reduction of the use of cement in the industry. In this work, the study of work methodologies for the manufacture of green cementitious grout mixtures is studied. Grout is widely used in construction and it requires an important use of raw materials. On the other hand, the steel industry faces the problem of the growing generation of slag wastes due to the increase in steel manufacturing. The green grout aims to achieve the dual objective of reducing the demand for cement and improve the slag waste valorization. Slag is not introduced as an aggregate but through the direct replacement of cement and no additives. The research seeks a product where we can use steel slag intensively, guaranteeing minimum resistance and workability. Results with substitutions between a 25% to 50% and water/cement ratio of 1 are presented. In particular, the suitability of different slags (two Ladle Furnace Slag (LFS) and one Blast Furnace Slag (GGBS)) in the quality of the final product are analyzed. The feasibility of replacing cement with slag and the importance of the origin and pretreatment are highlighted

Sustainable development of an Ultra-High Performance Fibber Reinforced Concrete (UHPFRC): towards partial replacement of cement by slags

The global production of concrete represents, every year, more than 5% of the anthropogenic emissions of carbon dioxide, mainly from the production of cement. This negative factor can be improved by incorporating supplementary cementitious materials in order to replace cement. In the last few decades, research has been conducted on what it is known as Ultra High Performance Fibber Reinforced Concrete (UHPFRC). The term includes a broad range of materials such as defect-free, dense particle, engineered composite, multi-scale particle and fibber-reinforced cementitious materials, with enhanced properties. UHPFRC has better mechanical and durability properties compared to normal strength concrete. Other benefits of using UHPFRC on a structure includes the reduction of concrete sections, concrete formwork, labour, equipment and time of construction. Despite of the benefits associated to this material, the UHPFRC is still struggling to be universally applied, mainly due to its high cost and its high environmental impact. UHPFRC cost is higher than normal concrete, due to a very high powder content and steel fibber addition. However, the production of UHPFRC using locally available materials, under normal curing conditions, should reduce its cost and turned it into a more attractive construction product. In this paper, the fresh and hardened properties of a specific UHPFRC composition are presented. The mixture replaces a significant percentage of cement by slags, and the results reveal the viability of the proposed mix. The environmental performance of the mixture confirmed the improvement on the material sustainability and allowed the identification of some potential future studies.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Slag Substitution as a Cementing Material in Concrete: Mechanical, Physical and Environmental Properties

A circular economy is a current tenet that must be implemented in the field of construction. That would imply the study of the possibilities of the use of waste generated, for obtaining materials the used in construction as replacements for the raw material used. One of these possibilities is the substitution of the cement by slag, which contributes to the reduction of cement consumption, decreasing CO2 emissions, while solving a waste management problem. In the present paper, di erent types of concrete made by cement substitution with di erent type of slags have been studied in order to evaluate the properties of these materials. Cement is replaced by slag from di erent steel mills, both blast furnace and ladle furnace slag. The percentages of slag substitution by cement are 30%, 40% and 50% by weight. Mechanical, physical and environmental properties have been evaluated. Compressive and flexural strength have been analysed as the main mechanical properties. As far as physical properties go, density and porosity tests were be reported and analysed, and from an environmental point of view, a leachate study was performed. It has been found that some kinds of slag (blast furnace slag) are very suitable as substitutes for cement, providing properties above those of the reference concrete, while other types (ladle furnace slag) could be valid for non-structural applications, contributing in both cases to a circular econom

Características mecánico-resistentes de hormigones fabricados con residuos siderúrgicos como conglomerantes y reducción de cemento

[ES] Uno de los principales problemas de la siderurgia en lo referente a la fabricación de acero, son los productos secundarios que se producen, provocando en los últimos años nuevos tipos de residuos industriales que, en función de la sostenibilidad del medio ambiente, son reutilizados o bien tratados. Este trabajo propone el análisis del comportamiento resistente de residuos en probetas de hormigón, como son polvos de humo provocados por hornos de arco eléctrico, cuando se produce la fusión de los materiales. Mediante la reducción de cemento y sustitución por este material, pueden tener una segunda vida en el mercado evitando que sean depositados en el vertedero.Parrón Rubio, ME.; Pérez García, F.; Contreras De Villar, F.; Rubio Cintas, MD.; Pelufo Carbonell, MJ. (2018). Características mecánico-resistentes de hormigones fabricados con residuos siderúrgicos como conglomerantes y reducción de cemento. En HAC 2018. V Congreso Iberoamericano de hormigón autocompactable y hormigones especiales. Editorial Universitat Politècnica de València. 525-534. https://doi.org/10.4995/HAC2018.2018.6127OCS52553

Performance characteristics of concrete packaged with electric arc furnace slag (LFS) and (GGBFS) to replace average aggregate.

One of the objectives sought today is the reuse of any type of waste and converting it into raw material for reuse. The study of different components in concrete for materials that go to landfill, minimizing the impact it causes on the environment can be a solution in civil engineering, minimizing risks and carrying out the study of different dosages to obtain an optimal result. This article studies the replacement of cement with different types of slag GGBFS (Ground Granulated Blast Furnace Slag) and LFS (Ground Granulated Blast Furnace Slag), at a percentage of 50%, with aggregates.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Concrete Properties Comparison When Substituting a 25% Cement with Slag from Different Provenances

Concrete consumption greatly exceeds the use of any other material in engineering. This is due to its good properties as a construction material and the availability of its components. Nevertheless, the present worldwide construction increases and the high-energy consumption for cement production means a high environmental impact. On the other hand, one of the main problems in the iron and steel industry is waste generation and byproducts that must be properly processed or reused to promote environmental sustainability. One of these byproducts is steel slag. The cement substitution with slag strategy achieves two goals: raw materials consumption reduction and waste management. In the present work, four different concrete mixtures are evaluated. The 25% cement substitution is carried out with different types of slag. Tests were made to evaluate the advantages and drawbacks of each mixture. Depending on the origin, characteristics, and treatment of the slag, the concrete properties changed. Certain mixtures provided proper concrete properties. Stainless steel slag produced a fluent mortar that reduced water consumption with a slight mechanical strength loss. Mixtures with ground granulated blast furnace slag properties are better than the reference concrete (without slag)

Influencia en la huella hídrica en la fabricación de hormigón con escorias de Cu y Polvo de Humo

El aprovechamiento de residuos y subproductos procedentes de la industria y su reutilización ayuda a conservar los recursos naturales al reducir la demanda de materias primas. Al mismo tiempo, se modera la sobreexplotación de los recursos naturales y propicia un mayor respeto medioambiental, sin olvidar las posibilidades técnicas y económicas que resultan fundamentales para el éxito de su aprovechamiento. El objetivo es desarrollar la aplicación de la escoria de cobre de vertederos, para su valorización como componente del hormigón (sustituyendo al cemento) que generen mejoras económicas y medioambientales en el proceso de transformación de un residuo en un producto reutilizable. En este estudio se pone de manifiesto como al sustituir el cemento por la escoria de cobre y polvo de humo, la mezcla es sumamente fluida, lo que nos ha llevado a tener que realizar sustracción de agua, con lo que se mejora la característica de Huella Hídrica, reforzando la competencia en la conservación del medio ambiente. La innovación radica en optimizar la cantidad de escoria de cobre que sustituiremos por cemento. Sin interrelacionarlo con la dosificación del árido ya investigado. Con esta nueva metodología se aprovecha al máximo un material desechable mediante la reducción del cemento conllevando una disminución en los costes, por la sustitución del residuoUniversidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Assessment of mechanical properties of concrete using electric arc furnace dust as an admixture

One of the main present challenges that all the countries have to engage with is the environmental degradation due to the human action. Industry generates high quantities of materials rendered useless during the manufacturing process. Electric Arc Furnace Dust (EAFD) is a hazardous industrial waste due to its high content in heavy metals. In this paper, the solidification of EAFD within the hydrated Portland cement matrix is proposed as a possible solution for its stabilization. Four concrete mixes were produced varying the content of EAFD as admixture (0, 5, 10 and 15% by weight of cement). The elastic modulus and the density of each concrete mixture were obtained in order to determine their mechanical properties. Results indicate that concrete mixtures that include EAFD as an admixture show a higher elastic modulus and a lower density in comparison with traditional concrete