scholarly journals Viability of Using High Amounts of Steel Slag Aggregates to Improve the Circularity and Performance of Asphalt Mixtures

2022 ◽  
Vol 12 (1) ◽  
pp. 490
Author(s):  
Caroline Moura ◽  
Lucas Nascimento ◽  
Carlos Loureiro ◽  
Mafalda Rodrigues ◽  
Joel Oliveira ◽  
...  
Keyword(s):  
Circular Economy ◽  
Mechanical Performance ◽  
Permanent Deformation ◽  
Steel Slag ◽  
Cost Effective ◽  
Asphalt Mixtures ◽  
Raw Material ◽  
Water Sensitivity ◽  
Natural Aggregates ◽  
And Performance

Steel slag is a byproduct generated as waste during the steelmaking process and can be considered a cost-effective and environmentally acceptable alternative to replace natural aggregates. Using steel slag aggregates (SSA) to produce asphalt mixtures promotes sustainability and circular economy principles by using an industrial byproduct as a raw material. Thus, this work mainly aims to design more sustainable asphalt mixtures with high amounts of SSA that fit the circular economy expectations. This work developed two asphalt mixtures with SSA for surface (AC 14 surf) and binder/base (AC 20 bin/base) courses. Initially, the excellent wearing and polishing resistance of SSA and their good affinity with bitumen demonstrated the potential of this byproduct to be used in asphalt mixtures. Then, when analyzing the influence of using two different SSA incorporation rates (50% and a percentage close to 100%) in both asphalt mixtures, it was concluded that the use of SSA should be limited to 75% to avoid excessive air void contents and durability problems. The importance of considering the different particle densities of SSA and natural aggregates was highlighted during the mix design by defining a relationship between an effective and equivalent binder content. Finally, the mechanical performance of AC 14 and AC 20 with 75% SSA incorporation was compared to identical conventional mixtures produced with natural granite aggregates. The results obtained showed that the asphalt mixtures with 75% SSA have some workability problems due to the rough and porous surface of SSA. However, they present an excellent water sensitivity and permanent deformation resistance, surpassing the performance of the conventional asphalt mixtures.

A Review of the Utilisation of Recycled Waste Material as an Alternative Modifier in Asphalt Mixtures

2020 ◽  
Vol 6 ◽  
pp. 42-60
Author(s):  
Abdalrhman Abrahim Milad ◽  
Ahmed Suliman B. Ali ◽  
Nur Izzi Md Yusoff
Keyword(s):  
Mechanical Performance ◽  
Permanent Deformation ◽  
Steel Slag ◽  
Asphalt Mixture ◽  
Construction Materials ◽  
Crumb Rubber ◽  
Asphalt Mixtures ◽  
Waste Material ◽  
Waste Materials ◽  
The Road

The possibility of using waste materials in road construction is of great interest as their utilisation may contribute to reducing the problems of hazard and pollution and conserve natural resources. Thus, there is an urgent need to find a sustainable method for using waste materials as a substitute in the standard asphalt binders. There are several concerns about the physical and chemical properties and mechanical performance of asphalt pavements incorporated with waste material in the effort to reduce permanent deformation of the road surface. This review article presents a brief discussion of the asphalt mixtures modified with waste material, and the recycled materials used as a modifier in the asphalt mixture. The present paper summarises the use of crumb rubber, crushed concrete, steel slag, glass fibre and plastic waste in asphalt mixtures. The use of waste materials as a modifier in asphalt mixture resulted in improved asphalt pavement performance. Results advocate that rubberised asphalt mixture with desired properties can be designed as an additive with a friendly environmental approach in construction materials. The researches that adopted the influence of usage, recycle waste material to improve the performance of the asphalt of the road are still limited compared to other construction fields. Doi: 10.28991/cej-2020-SP(EMCE)-05 Full Text: PDF

scholarly journals The Influence of the Affinity between Aggregate and Bitumen on the Mechanical Performance Properties of Asphalt Mixtures

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6452
Author(s):  
Maria M. A. S. Maia ◽  
Marisa Dinis-Almeida ◽  
Fernando C. G. Martinho
Keyword(s):  
Mechanical Performance ◽  
Road Traffic ◽  
Permanent Deformation ◽  
Asphalt Mixtures ◽  
Adhesion Promoter ◽  
Limestone Filler ◽  
Coarse Aggregates ◽  
Road Users ◽  
Water Sensitivity ◽  
Different Origins

Two of the main problems encountered in flexible pavements are the stripping of coarse aggregates and the formation of rut depth due to increases in the volume of road traffic and heavy vehicle loads, especially in areas where speeds are low. The existence of rut depth also affects the comfort and safety of road users due to the water accumulation on the pavement surface and reducing tire/pavement friction, which can lead to hydroplaning phenomena. In this research, it was proven that the use of fillers of different origins influences the affinity between aggregates and the binder. The effect of an adhesion promoter in the mix design (such as the amine included in cellulosic fiber pellets) was also studied. Several tests were carried out to determine the binder/aggregate adhesiveness, water sensitivity and resistance to permanent deformation, to evaluate the performance of different blends. It was found that the addition of this additive increased 10% of the aggregate surfaces covered with bitumen when compared with the aggregates without this addition. As expected, the water sensitivity tests showed that the mixture with granitic filler had the lowest indirect tensile strength ratio (ITSR) value (70%), while the mixtures with limestone filler led to the highest percentages (ranging from 83 to 93%). As for the results of the wheel tracking tests (WTT), it was confirmed that the use of limestone filler translates into an improvement in the performance against the permanent deformation of the asphalt mixtures. The mixture with higher bitumen content and adhesion promoter revealed the best average results.

scholarly journals Use of polymer modified binders as rejuvenators in recycled asphalt mixtures

2020 ◽  
Vol 13 (6) ◽  
pp. 654-664
Author(s):  
Hélder P. Torres ◽  
Sara R. M. Fernandes ◽  
Carlos D. A. Loureiro ◽  
Caroline F. N. Moura ◽  
Hugo M. R. D. Silva ◽  
...  
Keyword(s):  
Mechanical Performance ◽  
Permanent Deformation ◽  
Asphalt Mixture ◽  
Asphalt Mixtures ◽  
Production Costs ◽  
Waste Materials ◽  
Recycled Asphalt ◽  
Water Sensitivity ◽  
Modified Binders ◽  
Road Paving

AbstractRoad paving recycling has been acquiring more relevance in society, especially within the paradigm of a circular economy. The addition of waste materials in asphalt mixtures is an excellent solution to face the gradual emergence of a great diversity of waste materials and reduce the production costs. This study aims to evaluate the addition of commercial and laboratory-produced polymer modified binders as rejuvenators in recycled asphalt mixtures with high contents of reclaimed asphalt pavement material (RAP). A commercial polymer modified binder (PMB) and a conventional bitumen modified with 5% of styrene-butadiene-styrene (SBS) or 4% of Regefalt were added to RAP aged bitumen and compared with a rejuvenated binder. Fatigue, permanent deformation and water sensitivity tests carried out on recycled mixtures produced with those binders showed that polymer modified binders could be used as rejuvenators to improve their performance significantly. The recycled asphalt mixture produced with the commercial PMB presented the best mechanical performance. The polymer-modified binders revealed an ageing resistance equivalent to that of the control rejuvenated binder, or slightly better in the case of the final binder with SBS polymer.

scholarly journals Performance and Durability of Porous Asphalt Mixtures Manufactured Exclusively with Electric Steel Slags

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3306 ◽  
Author(s):  
Marta Skaf ◽  
Emiliano Pasquini ◽  
Víctor Revilla-Cuesta ◽  
Vanesa Ortega-López
Keyword(s):  
Mechanical Performance ◽  
Asphalt Mixture ◽  
Asphalt Mixtures ◽  
Electric Steelmaking ◽  
Porous Asphalt ◽  
Bituminous Mixtures ◽  
Abrasion Loss ◽  
Water Sensitivity ◽  
Electric Arc Furnace Slag ◽  
Furnace Slag

Electric arc furnace slag (EAFS) and ladle furnace slag (LFS) are by-products of the electric steelmaking sector with suitable properties for use in bituminous mixtures as both coarse and fine aggregates, respectively. In this research, the production of a porous asphalt mixture with an aggregate skeleton consisting exclusively of electric steelmaking slags (using neither natural aggregates nor fillers) is explored. The test program examines the asphalt mixtures in terms of their mechanical performance (abrasion loss and indirect tensile strength), durability (cold abrasion loss, aging, and long-term behavior), water sensitivity, skid and rutting resistance, and permeability. The results of the slag-mixes are compared with a standard mix, manufactured with siliceous aggregates and cement as filler. The porous mixes manufactured with the slags provided similar results to the conventional standard mixtures. Some issues were noted in relation to compaction difficulties and the higher void contents of the slag mixtures, which reduced their resistance to raveling. Other features linked to permeability and skid resistance were largely improved, suggesting that these mixtures are especially suitable for permeable pavements in rainy regions. In conclusion, a porous asphalt mixture was produced with 100% slag aggregates that met current standards for long-lasting and environmentally friendly mixtures.

Expansion Level of Steel Slag Aggregate Effects on Both Material Properties and Asphalt Mixture Performance

2019 ◽  
Vol 2673 (3) ◽  
pp. 506-515 ◽  
Author(s):  
Jamilla Emi Sudo Lutif Teixeira ◽  
Aecio Guilherme Schumacher ◽  
Patrício Moreira Pires ◽  
Verônica Teixeira Franco Castelo Branco ◽  
Henrique Barbosa Martins
Keyword(s):  
Material Properties ◽  
Mechanical Performance ◽  
Early Stage ◽  
Asphalt Binder ◽  
Steel Slag ◽  
Asphalt Mixture ◽  
Asphalt Mixtures ◽  
Mix Design ◽  
Expansion Level ◽  
Different Levels

The influence of steel slag expansion level on the early stage performance of hot mix asphalt (HMA) is evaluated. Initially, samples of Linz-Donawitz type steel slag with different levels of expansion (6.71%, 3.16%, 1.33%) were submitted to physical, mechanical, and morphological characterization to assess the effects of expansion on individual material properties. Steel slag was then used as aggregate in HMA to verify the effects of its expansion characteristics on the volumetric and mechanical performance of the asphalt mixture. Four different asphalt mixtures were designed based on Marshall mix design, using asphalt cement (pen. grade 50/70), natural aggregate (granite), and steel slag (in three different levels of expansion). The mechanical characteristics of the asphalt mixture were evaluated based on results from Marshall stability, indirect tensile strength, and resilient modulus testing. A modified Pennsylvania testing method (PTM) was also performed on the studied asphalt mixtures to verify the potential of asphalt binder film to minimize the expansive reactions of steel slag. It was observed that the level of steel slag expansion changes some of the material’s individual properties, which can affect the volumetric parameters of the mix design. The use of steel slag as aggregate in HMA also improves the mechanical properties of non-aged asphalt mixtures. Moreover, the expansive characteristics of this material could be minimized when combined with other asphalt mixture components.

Sewage Sludge as Raw-Material in Asphalt Mixtures

2013 ◽  
Vol 664 ◽  
pp. 638-643 ◽  
Author(s):  
Maria del Pilar Durante Ingunza ◽  
Olavo Francisco dos Santos Júnior ◽  
Sayonara Andrade Medeiros
Keyword(s):  
Mechanical Performance ◽  
Environmental Parameters ◽  
Empty Space ◽  
Asphalt Mixtures ◽  
International Standards ◽  
Raw Material ◽  
Air Voids ◽  
The One ◽  
Consequent Increase ◽  
Space Volume

The aim of this study is to assess the volumetric and mechanical behavior of concrete asphalt mixtures, using natural sludge as a partial substitute for the tiny aggregate and calcined sludge as filler. This assessment was performed based on technical and environmental parameters, using laboratory tests obeying current Brazilian norms, according to international standards. The addition of natural sludge to the mixtures has increased stability, increased air voids contents of the mixtures. The addition has compromised mixture adhesiveness. With respect to the addition of calcined sludge to the mixtures, the mixtures with calcined sludge displayed the same behavior as those with cement. It was observed decrease in empty space volume of the mixtures and consequent increase in empty space-bitumen relation and increased stability. The mixture addition of natural sludge that has the best mechanical and volumetric performance is the one with 7.5% of natural sludge in the granulometric composition of the mixture. The mixture with 1% of calcined sludge had the best volumetric and mechanical performance.

scholarly journals Effectiveness of Micro- and Nanomaterials in Asphalt Mixtures through Dynamic Modulus and Rutting Tests

2016 ◽  
Vol 2016 ◽  
pp. 1-14 ◽  
Author(s):  
Hui Yao ◽  
Zhanping You
Keyword(s):  
Dynamic Modulus ◽  
Mechanical Performance ◽  
Permanent Deformation ◽  
Asphalt Mixture ◽  
Asphalt Mixtures ◽  
Asphalt Binders ◽  
Test Results ◽  
Modified Asphalt ◽  
Overall Performance ◽  
Carbon Microfiber

The objectives of this research are to use micro- and nanomaterials to modify the asphalt mixture and to evaluate the mechanical performance of asphalt mixtures. These micro- and nanomaterials, including carbon microfiber, Nanomer material, nanosilica, nonmodified nanoclay, and polymer modified nanoclay, were selected to blend with the control asphalt to improve the overall performance of the modified asphalt binders and mixtures. The microstructures of original materials and asphalt binders were observed by the field emission scanning electron microscope (FE-SEM). The mixture performance tests were employed to evaluate the resistance to rutting and permanent deformation of the modified asphalt mixtures. Test results indicate that(1)the dynamic modulus of micro- and nanomodified asphalt mixtures improved significantly;(2)the rutting susceptibility of the modified asphalt mixtures was reduced significantly compared to that of the control asphalt mixture;(3)the microstructures of modified asphalt binders were different from the control asphalt, and the structures determine the improvement in the performance of modified asphalt mixtures. These results indicate that the addition of micro- and nanomaterials enhanced the rutting performance and strength of asphalt mixtures. In addition, the analysis of variance (ANOVA) was used to analyze the modifying effects of micro- and nanomaterials on the performance.

scholarly journals Evaluation of Warm Rubberized Stone Mastic Asphalt Mixtures through the Marshall and Gyratory Compactors

Materials ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 265
Author(s):  
Juan Gallego ◽  
Ana María Rodríguez-Alloza ◽  
Leticia Saiz-Rodríguez
Keyword(s):  
Greenhouse Gas Emissions ◽  
Greenhouse Gas ◽  
Mechanical Behaviour ◽  
Permanent Deformation ◽  
Warm Mix Asphalt ◽  
Asphalt Mixtures ◽  
Reflective Cracking ◽  
Mastic Asphalt ◽  
Water Sensitivity ◽  
Stone Mastic Asphalt

Stone mastic asphalt (SMA) mixtures exhibit excellent behaviour; they are highly resistant to reflective cracking and permanent deformation, as well as providing the wearing surface with an optimal texture. However, the production and compaction temperatures are similar to conventional mixtures, which means that there is a significant consumption of energy, as well as greenhouse gas emissions. Warm mix asphalt (WMA) technology, which has been developed over the last few years, might allow lower temperatures without compromising the mechanical behaviour of the mixtures. Also, over the last few decades, rubberized asphalt has proved to be effective in improving the performance and being environmentally suitable, but it requires higher production temperatures than conventional mixtures. In this study, several tests were performed to evaluate the effect of a chemical WMA additive on the compactability and water sensitivity of rubberized SMA mixtures with both the Marshall and the gyratory compactor. The investigation has shown that the gyratory compactor is more suitable for studying compactability and the water sensitivity of rubberized SMA with WMA additives.

scholarly journals DEFINING OF EAF STEEL SLAG APPLICATION POSSIBILITIES IN ASPHALT MIXTURE PRODUCTION / ELK PLIENO ŠLAKO PANAUDOJIMO GAMINANT ASFALTO MIŠINĮ GALIMYBĖS / ВОЗМОЖНОСТИ ПРИМЕНЕНИЯ СТАЛЬНОГО ШЛАКА ИЗ ДУГОВОЙ СТАЛЕПЛАВИЛЬНОЙ ПЕЧИ ДЛЯ ПРОИЗВОДСТВА АСФАЛЬТОВОЙ СМЕСИ

2011 ◽  
Vol 19 (2) ◽  
pp. 148-157 ◽  
Author(s):  
Tahir Sofilic ◽  
Ana Mladenovič ◽  
Una Sofilič
Keyword(s):  
Structural Characteristics ◽  
Heavy Traffic ◽  
Steel Slag ◽  
Steel Production ◽  
Asphalt Mixtures ◽  
Spectrometric Analysis ◽  
Steel Mill ◽  
Regular Production ◽  
Eaf Slag ◽  
Natural Aggregates

Electric arc furnace (EAF) steel slag, generated from carbon steel production process, is the most interesting from the asphalt technology point of view. This paper aims to explore the feasibility of utilizing steel slag as aggregates in asphalt mixtures. Characterization of EAF slag was carried out through examination of its physical and chemical properties with special emphasis on chemical and structural characteristics. Optical Microscopy (OM), X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectrometry (EDS) and γ-spectrometric analysis were employed to study the texture, morphology and composition of steel slag. Volume properties of steel slag were also evaluated as compared to those of natural aggregates. For this purpose the specimens of EAF slag were taken from the regular production processes in CMC Sisak, Croatia, Steel mill. The results which were obtained by testing geometric, physicalmechanic properties, as well as the properties of duration on the specimen of electric furnace steel slag of CMC Sisak, when compared to steel slag properties of other steel producers (Acroni, Jesenice, Slovenia and Štore Steel, Štore, Slovenia) and with properties of natural aggregates, have satisfied the conditions for manufacturing mixtures of the tested steel slag and natural stone, which can be used in asphalt production. In comparison to the natural aggregates, which are used in asphalt mixtures on highways and roads with heavy traffic, the examined steel slag has equally good physical and mechanical properties, while it is significantly better when it comes to resistance to polishing. Special attention has been given to the free CaO and free MgO, which can cause volume instability, thus limiting the use of steel slag in road construction. Santrauka Nagrinėjamos plieno šlako panaudojimo asfalto mišiniui gaminti galimybės. Šis šlakas susidaro elektros lanko krosnyje (ELK) anglies plieno gamybos procese. Nagrinėjamos fizikinės bei cheminės šlako savybės, pateikiamos cheminės ir struktūrines charakteristikos. Plieno šlako tekstūra, morfologija ir sudėtis nustatyta taikant optinę mikroskopiją (OM), rentgeno spindulių difrakciją (RSD), skenuojančiąją elektroninę mikroskopiją (SEM), energijos dispersinę spektrometriją (EDS) bei spektrometrinę analizę. ELK šlako mėginiai buvo paimti iš plieno gamyklos CMC Sisak, Kroatijoje. Šių mėginių geometrinės, fizikinės ir mechaninės bei patvarumo savybės buvo lyginamos su kitų šlakų (Acroni, Jesenice, Slovenija ir Store steel, Štore, Slovėnija) ir natūralių agregatų savybėmis. Gauti rezultatai patvirtino tirto plieno šlako bei natūralaus akmens panaudojimo gaminant asfaltą galimybes. Natūralūs agregatai, naudojami asfalto mišiniuose tiesiant greitkelius ir intensyvaus eismo kelius, bei tiriamas plieno šlakas turi panašių gerų fizikinių bei mechaninių savybių, tačiau ELK šlakas yra atsparesnis gludinimui. Daug dėmesio buvo skirta laisviesiems CaO ir MgO, lemiantiems medžiagos nepatvarumą. Šie oksidai yra pagrindinis veiksnys, ribojantis plieno šlako naudojimą asfaltui gaminti. Резюме В статье ставилась цель исследовать возможности применения стальных шлаков, образующихся в процессе производства стали в дуговой сталеплавильной печи (ДСП), для производства асфальтовой смеси. Исследовались физические и химические свойства шлака из ДСП. Текстура, морфология и состав стального шлака определялись с использованием оптической микроскопии, дифракции рентгеновских лучей, электронной микроскопии, энергодисперсной спектрометрии и γ-спектрометрического анализа. Образцы шлака из ДСП были взяты на заводе по производству стали в Хорватии. Геометрические, физико-механические и прочностные свойства образцов сравнивались со свойствами других шлаков (из Словении) и с натуральными материалами. Полученные результаты подтвердили возможность применения шлака исследованной стали и натурального камня для производства асфальтовой смеси. Натуральные материалы, применяемые в асфальтовых смесях при строительстве магистралей и дорог с интенсивным движением, и исследованный стальной шлак обладают приблизительно одинаковыми хорошими физико-механическими свойствами, однако шлак из ДСП более устойчив при шлифовании. При анализе большое внимание также уделялось свободным CaO и MgO, вызывающим нестабильность материала. Эти оксиды являются основным фактором, лимитирующим применение стального шлака при производстве асфальта.

Sign in / Sign up

Export Citation Format

Share Document