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Roads are currently essential links of communication and economic development. However, these roads are progressively requiring higher quality materials, implying a greater impact on the environment, in order to withstand the high levels of heavy vehicle traffic. Therefore, this research proposes the use of industrial by-products to create bituminous mixtures which are more resistant and durable than traditional ones. The industrial by-products used, are electric arc furnace slag, ladle furnace slag, and cellulose fibers from the papermaking industry. These by-products were physically and chemically characterized to be used to conform with bituminous mixtures. At the same time, bituminous mixtures were conformed with conventional materials, thus being able to compare the physical and mechanical properties of the conformed mixtures through different tests. The results showed how the use of cellulose fibers made it possible to absorb a greater percentage of bitumen, as well as the use of electric arc furnace slag and ladle furnace slag created mixtures, with greater Marshall stability. Therefore, sustainable, durable, resistant, and high waste mixtures were developed in this investigation. [ABSTRACT FROM AUTHOR]

Road construction is an activity that involves a large consumption of raw materials, with the consequent high environmental impact. For this reason, various research projects are being developed in which waste is used as a raw material for bituminous mixtures. This avoids the extraction of raw materials, reduces the environmental impact and reduces greenhouse gas emissions. In this research, the incorporation of ladle furnace slag as a filler for continuous grading bituminous mixtures was evaluated. Firstly, the ladle furnace slag was chemically and physically characterised and its suitability for use as a filler was determined in accordance with the regulations. Subsequently, bituminous mixtures were conformed with the slag and also with commercial fillers, calcareous and hornfels, in order to compare the results. Finally, the physical properties, Marshall stability and the effect of water were determined with the immersion–compression test on all families of samples. The results showed that the mixes conformed with ladle furnace slag had higher Marshall stability, less variation due to the effect of water and acceptable physical properties. Consequently, the suitability of utilisation of these slags in bituminous mixtures could be confirmed. [ABSTRACT FROM AUTHOR]

Power generation from biomass is one of the most promising energy sources available today. However, this industry has a series of wastes derived from its activity, mainly biomass fly ash and biomass bottom ash. Biomass bottom ash is a waste that has no current use and, in most cases, is deposited in landfills. In turn, road construction is one of the activities that produces the most pollution, as it requires huge amounts of raw materials. Therefore, this research proposes the use of biomass bottom ashes, in an unaltered form, for the formation of cold in-place recycling with bitumen emulsion. This type of mixture, which is highly sustainable owing to the use of a high percentage of waste, was made with reclaimed asphalt pavement, biomass bottom ash, water, and bitumen emulsion. To this end, the grading curve of the materials was analyzed, different bituminous mixtures were made with varying percentages of emulsion and water, and the mechanical properties of the mixtures were analyzed. At the same time, the same type of mix was made with reclaimed asphalt pavement and commercial limestone aggregate, in order to compare the results. The tests showed a better mechanical behavior of the bituminous mixes made with biomass bottom ash, maintaining physical properties similar to those of conventional mixes. In short, it was confirmed that the production of this type of mix with biomass bottom ash was feasible, creating sustainable materials that reuse currently unused waste and avoid landfill disposal. [ABSTRACT FROM AUTHOR]

The construction sector is one of the most demanding sectors for materials that exist today. Therefore, in order to avoid the extraction of new raw materials, it is necessary to use waste. This waste must present a series of physical and chemical characteristics that make it suitable for its employment. Therefore, in this investigation, ladle furnace slag is characterized for use as filler in bituminous mixtures. These slags are produced by the metallurgical industry in large quantities and represent a significant environmental problem. The slags were tested by analyzing their chemical composition and elementary physical properties. At the same time, and in order to evaluate the environmental viability, the environmental affections produced by the treatment of this material for its use as filler were calculated. These environmental results were compared with those obtained by processing of conventional filler. The detailed methodology reflected the chemical and physical feasibility of ladle furnace slags for use as filler, as well as the environmental advantage of processing this waste compared to commercial materials. In this way, the suitability of ladle furnace slags for bituminous mixtures and its feasibility for the creation of more sustainable pavements was assessed. [ABSTRACT FROM AUTHOR]

Road construction is an activity that demands a significant amount of aggregates for bituminous mixtures. In addition, these aggregates must be of a suitable quality for use, even more so on high traffic roads. In response to this problem, and in order to avoid the extraction of new raw materials, research is being carried out using industrial waste as a substitute for conventional aggregates. In this way, the extraction of raw materials is reduced and landfilling of waste is avoided. However, these wastes must have certain properties and environmental advantages over natural aggregates. Otherwise, the use of waste would not be environmentally beneficial but would be more damaging to the environment. For this reason, this research evaluates the viability of using electric arc furnace slag as aggregates for bituminous mixtures, the main objectives being the determination of the characteristics of the by-product, the particularities and the critical points to be taken into account for its subsequent use in mixtures. At the same time, the environmental advantages of treating this waste to obtain a usable aggregate are evaluated in comparison with the processing of a natural aggregate. The results showed that electric arc furnace slags have a suitable chemical composition and excellent physical and mechanical properties for use in bituminous mixtures, even on high traffic roads. At the same time, it was determined that their use produces a considerable reduction in environmental afflictions. Therefore, it could be affirmed that the use of electric arc furnace slags in bituminous mixtures is recommendable as a way to develop more sustainable materials for construction. [ABSTRACT FROM AUTHOR]

Cold in-place recycling with bitumen emulsion is a good environmental option for road conservation. The technique produces lower CO2 emissions because the product is manufactured and spread in the same location as the previous infrastructure, and its mixing with bitumen emulsion occurs at room temperature. Adding materials with cementitious characteristics gives the final mixture greater resistance and durability, and incorporating an industrial by-product such as ladle furnace slag (of which cementitious characteristics have been corroborated by various authors) enables the creation of sustainable, resistant pavement. This paper describes the incorporation of ladle furnace slag in reclaimed asphalt pavements (RAP) to execute in-place asphalt pavement recycling with bitumen emulsion. Various test groups of samples with increasing percentages of emulsion were created to study both the density of the mixtures obtained, and their dry and post-immersion compressive strength. To determine these characteristics, the physical and chemical properties of the ladle furnace slag and the reclaimed asphalt pavements were analyzed, as well as compatibility with the bitumen emulsion. The aforementioned tests define an optimal combination of RAP (90%), ladle furnace slag (10%), water (2.6%), and emulsion (3.3%), which demonstrated maximum values for compressive strength of the dry and post-immersion bituminous mixture. These tests therefore demonstrate the suitability of ladle furnace slag for cold in-place recycling with bitumen emulsion. [ABSTRACT FROM AUTHOR]

The construction sector is one of the most demanding of raw materials that exist at present. In turn, the greenhouse gas emissions that it produces are important. Therefore, at present there are several lines of research in which industrial by-products are incorporated for the manufacture of bituminous mixtures and the reduction of CO2 emissions, framed inside the circular economy. On the base of the aforementioned, in this research, bituminous mixtures of the Stone Mastic Asphalt type were developed with electric arc furnace slag, ladle furnace slag and discarded cellulose fibers from the papermaking industry. To this end, the waste is first characterized physically and chemically, and its properties evaluated for use in bituminous mixtures. Later, different groups of samples are conformed with conventional materials and with the waste in order to be able to compare the physical and mechanical properties of the obtained bituminous mixtures. The physical tests carried out were bulk density, maximum density and void index, as well as the Marshall test for the evaluation of the strength and plastic deformations of all the bituminous mixtures manufactured. The study and evaluation of the results showed that the incorporation of slag makes it possible to absorb a greater percentage of bitumen and obtain better mechanical properties, while maintaining a similar deformation and void content. Therefore, it is feasible to use the mentioned slags to create sustainable, resistant and suitable pavements for important traffic. [ABSTRACT FROM AUTHOR]

Pavement maintenance is an essential activity for maintaining the quality of the pavements. It is common for the ageing pavement to present problems of friction, so a proper solution must be provided. In this work, electric arc furnace slags are incorporated in slurry surfacing to provide adequate friction with this technique. The electric arc furnace slag was studied with physical, chemical, and mechanical tests to evaluate its suitability in the formation of the bituminous mixture. At the same time, different groups of samples were made with increasing percentages of bitumen emulsion and slag as coarse aggregate, determining the wear of the different families and the cohesion. The results reflected the excellent characteristics of the electric arc furnace slags, and an optimal combination of materials (slag, aggregate, water, and bitumen emulsion) could be obtained to develop slurry surfacing applicable to important traffic roads. This provided a use for the electric arc furnace slag in which its mechanical properties were used and a sustainable bituminous mixture with excellent characteristics and respectful of the environment was developed. [ABSTRACT FROM AUTHOR]

The construction of road infrastructure is one of the most polluting activities that exists today. Therefore, the use of waste from other industries is an excellent solution, since it reduces the consumption of raw materials, reduces CO2 emissions and avoids the disposal of waste in a landfill. In this study, electric arc furnace slag, cellulose fibers from the papermaking industry and bitumen emulsion were used for the conformation of sustainable and porous bituminous mixtures. Electric arc furnace slag was used as a high-resistance aggregate with a capacity sufficient to support traffic loads. Cellulose fibers were added to increase the percentage of binder in the mixture without bleeding problems, thereby achieving greater tensile strength. To do this, first the waste was physically and chemically characterized, then different mixtures were conformed and finally the mixtures were studied by means of the loss by wear and Marshall tests. The results reflected an optimal combination of materials that provided the best results in the mechanical tests, obtaining much better results than the mixtures with discontinuous grading and traditional bitumen emulsion. Therefore, a sustainable, porous and economical mixture for road use is obtained in this research. [ABSTRACT FROM AUTHOR]