Search

Traffic noise is the perpetual form of environmental pollution adversely affecting human health in urban environments. This literature review, intended for pavement researchers and professionals, l...

The incorporation of waste materials into road materials provides an excellent opportunity for partial reductions in virgin material consumption while providing a valuable alternative destination for the would-be waste. However, the incorporation of these materials and the performance limitations of the resulting asphalt need to be carefully examined, especially with regards to the asphalt cracking susceptibility. The current study focuses on the use of construction waste fillers as partial aggregate replacement in semidense asphalt (SDA) mixtures. Both concrete waste in the form of recycled concrete aggregates (RCA) and mixed construction and demolition (C&D) waste are examined. The indirect tensile (IT) stiffness modulus was found to not be affected significantly by the filler replacement. The IT fatigue resistance was found to be somewhat lower with the waste material using the classical approach, but similar when looking at the damage rate. In addition to the smaller-scale testing, larger-scale testing was conducted on the control and RCA filler mixtures using the Mobile Model Load Simulator (MMLS3), and similar cracking resistance was found for both mixtures while advancing a novel crack length measurement method using digital image correlation. The results showed that the incorporation of RCA filler into semidense asphalt mixtures is a viable solution reducing the need for virgin filler., Journal of Materials in Civil Engineering, 34 (6), ISSN:0899-1561, ISSN:1943-5533

Noise mitigation is the main advantage of semi-dense asphalt (SDA) pavements compared to traditional pavements such as stone-mastic asphalt (SMA), but noise is not quantitatively considered in traditional life cycle assessment (LCA). This article performs a comprehensive LCA for SMA and SDA including noise considerations. State-of-the-art sound emission and acoustical ageing models were used to determine the road traffic noise. The latest Swiss dose-response curves and current noise exposure data were used to evaluate health impacts due to noise. Additionally, traditional LCA is also included for assessing the greenhouse gas emissions, non-renewable cumulative energy demand and health impacts of non-noise processes. The results show that SDA causes around 70 % higher greenhouse gases and energy demand than SMA, primarily due to its shorter service life. However, the noise impacts in disability adjusted life years (DALYs) are higher by two to three orders of magnitude than non-noise processes, and the use of SDA can reduce 40 % of the total DALYs. It is shown that road traffic noise plays a significant role in the LCA of pavements. The trade-off between greenhouse gas and energy related impacts, on the one hand, and health effects, on the other hand, requires critical consideration by decision makers when promoting low-noise pavements., Science of The Total Environment, 842, ISSN:0048-9697, ISSN:1879-1026

Acknowledgments The Swiss company Innoplastics is acknowledged for providing the waste plastics. Empais participation is supported by Swiss National Science Foundation grant SNF 205121_178991/1 for the project titled “Urban Mining for Low Noise Urban Roads and Optimized Design of Street Canyons”. The participation of University of Belgrade, Faculty of Civil Engineering, is supported by the Ministry of Education, Science, and Technological Development of the Republic of Serbia under research project No. 2000092., This research aims to determine if the observed improvements using polyethylene (PE) waste in asphalt binder translate into better performance at the asphalt mixture scale in the laboratory environment while overcoming the stability and homogeneity issues experienced at the binder level. This is accomplished through a round-robin multinational experimental program covering four continents, with the active participation of eleven laboratories within the RILEM TC 279-WMR. PE modified AC16 mixtures were prepared employing the dry process using local materials with the PE waste provided by one source. Various mechanical tests were performed to investigate the compactability, strength, moisture sensitivity, stiffness and permanent deformation. Compared to the control mixtures, the following observations were made for PE modified mixtures: easier to compact, lower time dependence of stiffness, higher elastic behavior, lower creep rate, and higher creep modulus. Furthermore, cyclic compression test results showed that the resistance to permanent deformation is improved when using PE in asphalt mixtures, whereas the wheel tracking tests showed relatively similar or better results when 1.5% PE was added to the control mixture. The wheel tracking test results in water showed an increase in deformation with increasing PE content. The interlaboratory investigation showed that the use of PE as a performance-enhancing additive in asphalt pavements is a viable, environmentally friendly option for recycling waste plastic and could potentially reduce the use of polymer additives in asphalt., Swiss National Science Foundation grant SNF 205121_178991/1, Ministry of Education, Science, and Technological Development of the Republic of Serbia under research project No. 2000092

A literature review was conducted on the main aspects of asphalt binder extraction and recovery: i) extraction methods, ii) recovery methods and iii) solvents. The extraction methods include centrifuge, reflux and vacuum and others with particular focus on their effectiveness in dissolving the binder and the potential to modify it. Studies found that the centrifuge was a relatively safe cold extraction method that was fairly effective. For the recovery methods, the rotary evaporator was found to have a good reputation for relative ease of use and less binder modification than for the Abson method. The most commonly used solvents n-propyl bromide and chlorinated solvents, while being reusable, both had reported issues of ineffectiveness as well as major concerns about user safety. Bio-sourced solvents were found to be seldom used and required higher quantities. The study concluded that more research needed to be done in developing solvents.

The laboratory evaluation of the performance of a number of asphalt extraction solvents was conducted. The performance testing was conducted on unmodified and polymer modified asphalt binder with t...

In this paper, the combined effect of aging temperatures and cooling medium on the rheological properties of asphalt binder was experimentally investigated and evaluated. Two 70/100 penetration gra...

In view of increasing social and environmental consciousness, a circular approach in waste materials management in order to convert them into new secondary resources is becoming more necessary. Given this context, an interlaboratory testing program (ILTP) focusing on maximizing the use of waste aggregates replacing conventional virgin ones has been launched in the framework of the RILEM Technical Committee on “Valorisation of Waste and Secondary Materials for Roads”. Construction and demolition wastes, recycled concrete aggregates and steel slags were selected as waste aggregates to be investigated. A reference mixture prepared with natural virgin aggregates was al-so considered for comparison purposes. This paper describes the results achieved during the first steps of the ILTP concerning: i) the basic characterization of the selected marginal aggregates; ii) the Marshall mix design of different asphalt mixtures prepared with one or more waste aggregates. Overall, the experimental results collected during these preliminary steps seem to confirm that the selected marginal aggregates can be considered as valid alternatives for the traditional road materials, while not jeopardizing their performance

Durability characteristics of cement paste with two types of metakaolin (MK1 and MK2) replacement were examined. "Fluidized bed" calcination produced MK1 which was relatively pure, while "flash" calcination produced MK2, which had a high amount of quartz mixed in. At a 50% replacement after 28 days, porosity increased by 8.9 and 7% for MK1 and MK2 while primary sorptivity decreased. Thermogravometric and XRD analysis showed a decrease in the portlandite content by 79 and 75% for MKI and MK2, while the CaCO3 level did not change significantly. MK2, at an optimal replacement range of 5-30% produced relatively more CSH than MK1. Observed by SEM, metakaolin particles in MK2 were consumed by the pozzolanic activity more thoroughly than the particles of quartz. Metakaolin replacement levels of 20% or more for MK1, and 25% or more for MK2, made the cement paste very susceptible to carbonation ingress. Hydration stopping with propan-2-ol appeared to cause cracking while freeze-drying worked with no apparent problems. M

Incorporating crumb rubber (CR) using the dry process, directly in the asphalt mixture rather than into the bituminous binder requires no plant retrofitting, and therefore is the most practical industrial method for CR incorporation into asphalt mixtures. Nevertheless, very few large scale studies have been conducted. This work uses a holistic approach and reports on the functional and environmental performance of asphalt mixtures with different concentrations of CR fabricated employing the dry process in asphalt plants. Gaseous emissions were monitored during the production and laboratory leaching tests simulating the release of pollutants during rain, was conducted to evaluate the toxicology of both the CR material alone and the modified asphalt mixtures. In addition, laboratory compacted samples were tested to assess their fatigue behavior. Furthermore, noise relevant surface properties of large roller compacted slabs were evaluated before and after being subjected to a load simulator (MMLS3) to evaluate their resistance to permanent deformation. The results confirm that comparable performance can be achieved with the incorporation of CR using the dry process for high performance surfaces such as semi-dense asphalt, which usually require the use of polymer modified binders. Environmental performance improvement can be achieved by a washing step of the CR material that could remove polar CR additives which have commonly been used as vulcanization accelerator during rubber production.

Waste plastic in low noise asphalt mixtures can be a viable alternative to asphalt mixtures with polymer modified bitumen. The performance of low noise semi dense asphalt (SDA) mixtures with waste polyethylene (PE) plastic is investigated. The cyclic compression test (CCT) and semi-circular bending (SCB) test was used for characterization of high and low temperature performance. The CCT results revealed that the PmB mixture had shown significantly higher resistance compared to the PE mixture. However, the PE modification showed some improvements in terms of CCT loading when compared with mixtures using the same base binder without PE. The SCB test results found that on average using higher content of PE mixtures had slightly improved fracture energy and lower fracture toughness compared to asphalt mixtures using polymer modified binder (PmB). The electron microscopy images showed that the PE does not completely melt during the mixing process and exists as elastic bodies within the mixture. The findings showed that at low temperatures, both PE and binder behave elastically, whereas at higher temperatures, PE remains elastic, and binder's viscoelasticity becomes dominant. These results highlight the importance of selecting proper base binder for such modifications with waste plastic., Construction and Building Materials, 348, ISSN:0950-0618

The chemical properties and microstructural features of two straight-run virgin asphalt binders (PG 52-34 and 58-28) and a reclaimed asphalt pavement (RAP) binder as well as their corresponding saturate, aromatic, resin, and asphaltene (SARA) fractions were examined. Additionally, the properties of the binders with laboratory and plant mixture blending were also observed. Examining the corresponding SARA fractions revealed that the increases in the carbonyl index of RAP relative to the virgin binders were mainly found in the resin and asphaltene fractions, while the increase in the sulfoxide index is mainly found in the asphaltene fraction. The chemical properties were examined using Fourier transform infrared spectrometry. The RAP binder showed a significant increase in the indices of the carbonyl (IC═O) and sulfoxide (IS═O) functional groups compared to the virgin binders. The plant blended binders showed that additional silo storage at the plant increases the carbonyl index. The microstructural feature...

The physical and microstructural properties of four straight run asphalt binders were examined and compared in combination with short term aging (RTFOT) and long-term (PAV) laboratory aging. RTFOT aging was conducted at temperatures of 123, 143 and 163 °C. The physical testing parameters included penetration, softening point and Dynamic Shear Rheology (DSR) complex shear modulus and phase angle at 10 °C. The binders selected came from four different sources and had the same penetration grading (70/100). They all showed an increase in stiffness with aging, including with the increase in RTFOT temperatures and especially with PAV aging. The microstructural evolution of the binder was examined by Environmental Scanning Electron Microscopy (ESEM) on aged binders at 123 and 163 °C. The physical changes with aging corresponded to an evolution in the binders’ ‘fibril’ microstructure under ESEM, as a result of electron beam exposure, with the microstructure getting denser with PAV aging. This densification (fibril area) of the microstructure was quantified with image analysis for the virgin and RTFOT aged samples, and the fibril formation time was also measured. The asphalt binders showed varied ESEM ‘fingerprints’ and aged in different ways. The ESEM ‘formation time’ and ‘fibril area’ of the binders generally showed good correlation with the physical properties, although this was not the case for all of the binders due to their unique aging characteristics.

Asphalt is a self-healing material that has the ability to restore part of its stiffness and strength during rest periods and elevated temperatures, leading to a significant extension in service life. The self-healing of asphalt mixtures has been investigated in this paper using a modified tension-compression fatigue test. Asphalt mixture specimens, prepared with different binders (neat and SBS polymer modified) and gradations, were sinusoidally loaded in strain control mode, with a rest period being introduced at the end of each loading period. Rest period temperatures varied at 0, 10 and 20 °C. This loading-rest sequence was repeated three or four times. For some tests, the samples were loaded to complete failure after the final rest period. The asphalt mixture with the polymer modified asphalt had much better resistance to fatigue loading compared to the samples with neat binder. The stiffness of the sample represented by the norm of complex modulus (|E∗|) showed an increase during the rest periods. The fatigue life in terms of number of loading cycles was higher with an increase in rest time temperatures. Moreover, the fatigue life values of the samples with rest periods were significantly higher than for continuously loaded samples loaded under the same conditions.

In order to improve the sustainability of the low-noise Semi-Dense Asphalt (SDA), the aggregate fractions were replaced by recycled concrete aggregates (RCA), an abundant construction waste. The aggregate replacement was conducted by fractions of 2/4 and 0.125/2 mm corresponding to the 2/4 mm (coarse), 0.063/4 mm (sand) fractions of the control virgin aggregates, at about 15% replacement by volume of the control mixture for each fraction. Additionally, RCA filler replaced the control filler entirely, bringing the replacement level to over 20% of the total mixture. The binder was added at the same amount as the control binder and +0.5%, with additional binder compensating for the estimated increase in binder absorption in RCA. The wheel track rutting test at 60 °C indicated marginally improved performance with RCA sand replacement. However, low temperature semi-circular bending (SCB) test at 0 °C showed that there is a 10% reduction in cracking resistance using RCA coarse and 20% for RCA sand. The laser texture scanning indicated a small reduction in the texture level for the RCA samples before wheel tracking, and very similar texture profiles with the control after the wearing of the samples, indicating no significant effect in non-acoustic noise reduction properties. This study suggests that the use of RCA fractions in porous SDA surface mixtures is possible with particular attention to mixture optimization to improve rutting performance.

The observation of asphalt binder with the environmental scanning electron microscope (ESEM) has shown the potential to observe asphalt binder microstructure and its evolution with binder aging. A procedure for the induction and identification of the microstructure in asphalt binder was established in this study and included sample preparation and observation parameters. A suitable heat-sampling asphalt binder sample preparation method was determined for the test and several stainless steel and Teflon sample moulds developed, finding that stainless steel was the preferable material. The magnification and ESEM settings conducive to observing the 3D microstructure were determined through a number of observations to be 1000×, although other magnifications could be considered. Both straight run binder (PG 58-28) and an air blown oxidised binder were analysed; their structures being compared for their relative size, abundance and other characteristics, showing a clear evolution in the fibril microstructure. The microstructure took longer to appear for the oxidised binder. It was confirmed that the fibril microstructure corresponded to actual characteristics in the asphalt binder. Additionally, a 'bee' micelle structure was found as a transitional structure in ESEM observation. The test methods in this study will be used for more comprehensive analysis of asphalt binder microstructure.

Fluorescent technique has been used to characterise the morphology of polymer modified bitumen for years. However, the main problem of this technique is a missing standardised protocol for image ca...

Waste concrete is one of the most highly produced types of waste in the urban environment and finding a means for its re-use is crucial to making infrastructure sustainable. Semi-Dense Asphalt (SDA) is a type of asphalt mixture, which is commonly used in Switzerland to reduce pavement noise. This study examined the use of various fractions of Recycled Concrete Aggregates (RCA) into SDA mixtures. The virgin aggregates were replaced by RCA in selected fractions of 2/4 and 0.125/2 at 100% and 50%, with only one fraction being replaced for any single mixture. The mixtures were evaluated by volumetrics, indirect tensile strength and water sensitivity (EN 12697-12) in order to assess the effects of each RCA fraction. The results showed that RCA coarse aggregates absorb high amounts of binder, which is not the case for the RCA sand. The ITS results showed increase peak load for the RCA replacement samples but also increased brittleness. The ITSR% was similar to the control for lower fraction of RCA replacement samples, but significantly lower with higher replacement.

The properties of several asphalt binders with gradual styrene-butane-styrene (SBS) polymer modification were studied. The base binders used were straight-run PG 52-34, 58-28 and 64-28 which were modified with polymers at concentrations of 0, 1, 2, 3 and 4%. Two types of SBS polymers were used with different grain sizes and they were integrated into the binder with the same cross-linking agent. The rheological properties were studied using a Dynamic Shear Rheometer (DSR) with Temperature-Frequency Sweep Master Curves and the Multiple Stress Creep Recovery (MSCR) Test. The Master Curves showed that the polymer modification, up to 4% addition, increases the binder stiffness at high temperatures, which is a good indication of improved rutting resistance. The MSCR test showed improved percent recovery and compliance with increasing concentrations of SBS. To observe the effects of polymer addition on a microscopic level, the unaged binders were analyzed with the Environmental Scanning Electron Microscope (ESEM), finding that there were no significant changes with the level of polymer addition.

The use of waste plastics in partial asphalt binder replacement and substitute for polymer modification has the potential to contribute to the sustainability of road infrastructure as well as preservation of natural resources. In this study, two types of polyethylene (PE) waste plastics PE-pellets and PE-shreds (a by-product of the former, currently incinerated after production) were blended with a conventional asphalt binder in order to analyze their effect on the chemo-mechanical and thermal behavior. Particular attention was paid to the characterization of the waste PE as well as to the description of sample preparation, lacking in other studies. Differential Scanning Calorimetry (DSC), Thermal Gravimetric Analysis (TGA), Fourier Transform Infrared (FTIR) spectroscopy and Environmental Scanning Electron Microscopy (ESEM) were used to assess the different types of PE and blended asphalt binder's thermal properties, chemical modification degree and quality of blending, respectively. The rheological performance of waste PE blended binder was obtained using the Dynamic Shear Rheometer (DSR). The results illustrated that compared to commercial polymer modified binders, the binder resistance against high temperature distresses such as rutting could improve substantially with adding waste PE. The modulus of the binders at low temperatures was comparable. However, the negative results of high temperature storage stability of the PE blended binders indicated that attention needs to be paid to the mixture preparation method.

There have been a several studies observing bitumen microstructure using the environmental scanning electron microscope (ESEM); however, these have been few and far between. Nevertheless, there hav...

The increasing consumption of natural resources for road construction and generation of urban waste materials are two global ecological problems. Urban mining aims to convert waste materials into raw materials for industrial production, and as a result, address both problems simultaneously. This study explores the potential of urban mining for asphalt pavement surface courses. In the first part, as each country/region has its unique challenge with waste materials, a screening method taking the EU and Switzerland as case studies is employed to select waste materials that potentially qualify for asphalt surface courses. The second part presents a review of laboratory studies regarding the performance of asphalt mixtures with selected waste materials. Based on the industrial experience, the third part discusses the technology, specifications and cost considerations of asphalt surface courses with waste materials. Furthermore, the technical maturities for using waste materials are estimated in terms of technology readiness level (TRL). Overall, the paper demonstrates that various categories of waste materials can be potentially used in asphalt surface courses, revealing urban mining opportunities. The selected waste materials may improve the performance of asphalt mixtures with optimization of several factors, such as the fraction size and amounts of waste materials for addition or replacement. The TRL results showed that using crumb rubber (wet process) and steel slag are currently more mature than using other waste materials in asphalt surface course.

Recycled Concrete Aggregates (RCA) form a significant part of construction and demolition waste and its recycling is crucial for long-term construction sustainability. This study examined the incorporation of various fractions of RCA in Semi-Dense Asphalt (SDA) mixtures. The control SDA aggregates were replaced by RCA in selected fractions of 2/4 mm (coarse) and 0.125/2 mm (sand) at 100% and 50% each, and the filler at 100% of the fraction. The replacement was performed by mass with only one fraction being replaced for any single mixture. The mixtures were evaluated by their volumetrics, indirect tensile strength (ITS), water sensitivity (EN 12697-12), fracture energy and rutting resistance (EN 12697-22), in order to assess the effects of each RCA fraction on the mixture properties. The results showed that RCA coarse aggregates absorb significant amounts of binder and require more energy for compaction, which is not the case for the RCA sand or filler. The ITS results showed increased peak load for the RCA replacement samples but also increased brittleness in terms of resistance to crack initiation and propagation. RCA sand incorporation decreased the fracture energy at a higher rate than the coarse per total amount replaced. The ITSR% was similar to the control for lower amounts of RCA replacement, but significantly lower with higher replacement. The rutting resistance improved with RCA sand and especially coarse aggregate replacement. The study shows some limitations for use of RCA in asphalt mixtures, but also the potential for using them when the replacement rate is limited and replacement by volume is recommended. The RCA filler performance was very similar to the virgin filler, which makes its use in asphalt mixtures especially promising.

International audience; The objective of this study is to develop bio-sourced waste chemicals for use as asphalt release agents. Glycerol was extracted from bio-sourced waste and transformed by transesterification into the surfactants undecenoates of glycerol (MUG) and undecenoates of diglycerol (MUDG). They were composed of glycerol, monoglycerol, diglycerol, triglycerol, tetraglycerol and water. The formulations were mixed separately with water at quantities of 5-50%, along with acetone and commercial bio-sourced ARAs in order to observe the effects. The formulations were subjected to performance testing with the asphalt slide test, finding significant reduction in adhesion for a number of different formulations. The interaction of the formulations with bitumen was tested by the bitumen degradation test, which was combined with FTIR-ATR analysis, finding that the formulations do not dissolve the bitumen, but rather were adsorbed by the bitumen. The effects on asphalt mix of the best performing formulation, MUG at 20% in water, was tested by indirect tensile strength, determining that the formulation was acceptable for use in the field.

The physical and microstructural properties of four straight run asphalt binders were examined and compared in virgin state and in after short term aging (RTFOT) and long-term (PAV) laboratory aging. RTFOT aging was conducted at 123, 143 and 163 °C. Physical testing parameters included penetration and softening point. Selected binders came from four different sources with same penetration grade. They all showed an increase in stiffness with aging, and RTFOT temperatures. The microstructural evolution of the binder was examined by Environmental Scanning Electron Microscopy (ESEM) on aged binders at 123 and 163 °C. The physical transformation corresponded to an evolution in the binders’ ‘fibril’ microstructure under ESEM as a result of electron beam exposure, with the microstructure getting denser with PAV aging. The asphalt binders showed varied ESEM ‘fingerprints’ and aged in different ways. The ESEM properties generally showed to evolve with the physical properties, although this was not the case for all of the binders due to their unique aging characteristics.

The Rilem Technical Committee on Chemo Mechanical Characterization of Bituminous Materials has investigated the effect of short term aging temperature on long term properties of asphalt binder, chemically, physically and microstructurally. The increased use of warm mix asphalt (WMA) technologies warrants such investigations in order to validate laboratory aging procedures. To this end, penetration, softening point, Fourier Transform Infrared Spectroscopy, dynamic shear rheology (DSR) and electron microscopy (ESEM) were used. The experimental results on binders and warm (WMA) and hot (HMA) mixtures from nine participating laboratories indicate that the binder source, as well as method of evaluation, result in different rankings and behaviors among the four binders used. The TC recommends the development of appropriate RTFOT aging temperatures for the simulation of binder aging in WMA.

The study detailed in this paper examined the influence of two types of metakaolin (MK1 and MK2) at high replacement rates on the carbonation rate of cement paste. “Flash” calcination produced MK1, which had a high amount of quartz mixed in, while “fluidized bed” calcination produced MK2, which was relatively pure. The metakaolins were incorporated into the cement paste at rates of up to 50% by weight of cement and cured for 90 days. With regard to durability, MK replacement increased water porosity and susceptibility to carbonation, while water adsorption and primary sorptivity decreased. Thermogravimetric analysis (TGA) and X-ray Diffraction (XRD) analysis of the hydration phases showed a decrease in portlandite (Ca(OH) 2 ) content with MK replacement, increasing carbonation susceptibility. Decreased portlandite showed a strong correlation with an increased carbonation rate, indicating that these are primary factors in metakaolin cement paste carbonation. With TGA deconvolution, MK1 significantly increased CSH content up to a replacement level of 20%, while replacement levels over 30% appeared to reduce CSH formation. MK2 replacement did not have as significant an effect on CSH formation, corresponding with the higher primary sorptivity and greater susceptibility to carbonation penetration of MK2.

The use of reclaimed asphalt pavement (RAP) is of great significance for alleviating the problem of resource waste and land space occupation in the context of asphalt pavement. However, the use rate of RAP is still low in many countries because of limited understanding and no unified recycling guidelines, especially in terms of materials classification and aging grades. In this study, reclaimed asphalt pavements from sixteen different sections in southern China were collected, including with base and polymer modified asphalt (PMA). The performance of the reclaimed asphalt binder (RAB) at low, average and high temperatures was tested, using various methods, to find suitable indexes for categorizing aging grades. The viscosity (135 °C) and penetration (25 °C) were found to distinguish the aging degree of RAB the most consistently, and served as the indices to classify the RAB into different grades. To simplify the evaluation of aging grades, a comprehensive service life was determined using the Analytic Hierarchy Process, taking service years and surface levels into account. As a result, a good correlation was found between comprehensive service life and the aging grades.

WOS:000373963700024; International audience; The objective of this study is to develop testing methods of asphalt release agent (ARA) performance and the degree to which they may damage the asphalt. The testing of ARA performance demonstrated their ability to reduce the adhesion between the asphalt and the surface of steel (asphalt tools, truck bedsaEuro broken vertical bar) by the asphalt slide test, which provided two indicators for quantifying performance. The testing of the their damage to asphalt consisted of the measurement of the degree to which the compacted asphalt is damaged by the ARA including CBR resistance, indirect-tensile strength and bitumen degradation testing, the latter also serving as a test to find the most effective bitumen remover (BR). For asphalt degradation, the indirect tensile strength test provided more consistent results than CBR resistance.