Virgin Binder Research Articles

Laboratory and Field Evaluation of HMA with High Contents of Recycled Asphalt Pavement

AbstractTo determine if a higher percentage of recycled asphalt pavement (RAP) materials can be used in Iowa’s state highways, three hot mix asphalt (HMA) test sections with RAP amounts of 30.0, 35.5, and 39.2% were constructed. RAP materials were fractionated to meet Superpave mix design requirements. The field densities of all test sections were measured at 94.0% and higher. After 20,000 passes were applied using a Hamburg wheel tracking device, rut depths were less than 3 mm for all field mixtures. The binder was extracted from the field mixtures to identify the effect of RAP materials on the virgin binder. The extracted asphalt from test sections with 30.0, 35.5, and 39.2% fractionated RAP (FRAP) materials were stiffened from performance grade (PG) 64-28 (virgin binder) to PG 76-22, PG 76-16, and PG 82-16, respectively. To evaluate the low-temperature cracking behavior, a semicircular bending (SCB) test was performed on laboratory-compacted field mixtures. As the amount of FRAP materials increased, th...

Complex modulus and fatigue performances of bituminous mixtures with reclaimed asphalt pavement and a recycling agent of vegetable origin

The paper focuses on the investigation of the effects of a recycling agent on mechanical performances of bituminous mixtures produced with reclaimed asphalt pavement (RAP). Twenty-one different bituminous mixtures were produced and tested, using three distinct virgin binders (15/25, 35/50 and 70/100 penetration grades), with RAP contents varying from 0% to 60%. Seven of the mixtures were produced by adding a recycling agent of vegetable origin (its content was fixed equal to 3.5% by weight of the RAP binder). One of the mixtures is a 100% RAP mixture, produced only with RAP-extracted binder and aggregates issued from RAP material. Another one is a “perfect” mixture, produced by perfectly blending 70/100 base binder with 60% RAP-extracted binder and using this blend to coat virgin and RAP aggregates. Material properties were investigated using classical tests commonly performed by the road paving industry in Europe, in order to assess the impact of the addition of the recycling agent according to the current standard procedures. In particular, complex modulus |E*| (at 15°C and 10 Hz) and fatigue parameters 6 and 1/b (at 10°C and 25 Hz) were determined by means of two-point bending tests on trapezoidal samples. The addition of the recycling agent was observed to generally lower |E*| and improve fatigue performances of mixtures with a RAP content equal or greater than 40%.

RHEOLOGICAL BEHAVIOUR OF COCONUT SHELL POWDER MODIFIED ASPHALT BINDER

The objectives of this study were to determine the blending parameters of coconut shell powder (CSP) modified asphalt binder and to evaluate the rheological properties of CSP modified asphalt binder. CSP of 2%, 4%, 6%, 8% and 10% by weight of asphalt have been incorporated into an unaged 80/100 asphalt mix in order to improve its performance. The influence of the additives on the physical and rheological properties was evaluated with penetration test, softening point, storage stability, dynamic shear rheometer test (DSR), and Field Emission Scanning Electron Microscope (FESEM). The aging of asphalt binders was simulated in a laboratory by using Rotational Thin Film Oven (RTFO). The results showed that the addition of CSP into virgin binder was decreasing the penetration value and increasing the softening point temperature compared to the original binder. On the rheological effect, for unaged modified binder, higher CSP resulted higher G*/sin δ especially at lower temperature compared to the unaged control binder. Besides, for the aged modified binder, stiffness was lower than the control aged binder for all temperature.

Study on bond properties between RAP aggregates and virgin asphalt using Binder Bond Strength test and Fourier Transform Infrared spectroscopy

Since the aged asphalt film coating Reclaimed Asphalt Pavement (RAP) aggregates has prevented virgin asphalt from directly attaching to the aggregates, the mechanism behavior developed between RAP aggregates and virgin asphalt should be considered differently. In order to directly measure bond strength between RAP aggregate and virgin binder, the Binder Bond Strength (BBS) test was performed, and artificial coated RAP substrates were prepared employing an innovative coating treatment. The aged asphalt film thickness and the aging level of RAP substrate, combined with dry and wet curing conditions were assessed regarding to their impact on bond strength. Fourier Transform Infrared (FTIR) spectroscopy was also utilized to investigate the effect of film thickness and aggregate type on aging properties.According to BBS test results, existence of aged asphalt film had positive effects on bond properties under dry conditions. Moisture weakened this enhancement and induced more debond at the diffusion zone where the aged film and virgin asphalt blend. A proper aging level may exist at which RAP can provide optimum bond properties. Moreover, through FTIR spectroscopy, a good correlation between oxidation and film thickness was observed.

Rational Performance Indicators to Evaluate Asphalt Materials’ Aging Characteristics

AbstractThere is very limited literature regarding asphalt mixture aging evaluation using asphaltene as a parametric assessor. However, a few studies have recommended that aging characteristics of asphalt mixtures be evaluated by utilizing the potentiality of asphaltene as a rational aging indicator and formulate a methodology to assess long-term flexible pavement performance. The main objective of this research was to investigate the aging behavior of asphalt binders and mixtures, and develop aging indices and parametric models with asphaltene as a rational performance indicator based on fundamental asphalt material characteristics. Asphaltene content increased from short- to long-term aged condition with rubber- and polymer-modified binders depicting higher magnitudes than the virgin binders. During aging, because of absorption of oils, asphaltene contents do not increment superfluously, furthering modified binder particularly rubber modified bitumen to age at a slower rate. The effect of asphalt mixtur...

Investigation on influence of nanoclay addition on rheological performance of asphalt binder

Organo-modified nanoclay has got considerable attention in recent years to improve the performance of asphalt binders. However, various aspects such as rutting performance using Multiple Stress Creep Recovery (MSCR) test, fatigue performance using Linear Amplitude Sweep (LAS) test and ageing resistivity potential using advanced rheological parameter are still unexplored for better rheological characterisation. The present study deals with rutting, ageing resistivity potential and fatigue performance of asphalt binder (AC-10) modified with organo-modified nanoclay (CL-30B). Different percentages (0, 2, 4 and 6% by weight of binder) of CL-30B were mixed with AC-10 using a high-shear mixer. Different rheological studies, such as Brookfield viscosity, Superpave performance grading, time–temperature sweep, MSCR and LAS tests, were conducted on CL-30B-modified asphalt binders. Effects of CL-30B on performance were observed to be predominant in intermediate to high-temperature range as obtained from the master curve. The ageing resistivity of asphalt binder increased with the addition of CL-30B. The Superpave rutting parameter (G*/Sinδ) increased and non-recoverable creep compliance (Jnr) estimated from MSCR decreased with inclusion of CL-30B, indicating a better rutting performance of asphalt binders. The number of cycles to fatigue estimated from the LAS test showed improvement in fatigue performance of asphalt binder with addition of CL-30B. The high-temperature performance grade of CL-30B-modified binder was found to be higher compared to virgin binder. The relationship between Jnr and G*/Sinδ, and recovery (R) and storage modulus (G′) parameters are presented in this paper. In addition, ranking of asphalt binder based on various parameters (i.e. G*/Sinδ, AI, Jnr, R, Nf) is discussed in this paper.

Studying the effect of soft bitumen on the rheological properties of reclaimed PMB binder by using the DSR

A rapidly increasing source of reclaimed asphalt (RA) containing polymer-modified bitumen (PMB) offers a potential premium material contribution when performing recycling. This manuscript studies the influence of soft virgin paving grade binder and PMB binder on the rheological properties of three PMB-containing RA binders from different ‘old’ surface-layer asphalt mixtures in Europe, by using the dynamic shear rheometer (DSR). The results indicated that the soft virgin binder and PMB binder can change the flow abilities of RA binder. After the normalisation, the Cole–Cole curve for the modulus can be used to describe the influence of soft fresh binder on the rheological properties of reclaimed binders. The Cole–Cole curve in terms of the viscosity can be used to describe the colloidal shifting of reclaimed binder when blending with fresh binder, and the fresh binder dominated the structure of blended binders. Mixing with soft PMB binder made it possible to rejuvenate the rheological properties of the reclaimed PMB binder. Then, the polymer from the reclaimed binder can still function in a new mixture when recycled.

Towards 100% recycling of reclaimed asphalt in road surface courses: binder design methodology and case studies

Reclaimed Asphalt (RA) has shown great potential to be reused in new asphalt mixtures, however its incorporation in top asphalt pavement layers is still very limited (10–30%). In fact, despite the advantages that its use implies, RA content in road pavement surface courses is still restricted in most countries due to mainly legislation limitations, but also some technical issues. This paper aims at being a step further to improve the latter by providing a methodology that allows producing fundamental inputs for confidently performing mix design of asphalt mixtures incorporating up to 100% RA. The methodology consists in an advanced preliminary binder's blend design that can be used with any type of RA and also in presence of rejuvenators. This procedure includes in the production of blending charts and laws that considers the uncertainties on accounting the extent of final binder content, Degree of Blending and Replaced Virgin Binder. The description of the methodology is accompanied with results of two extreme case studies consisting in the preliminary design of binders for asphalt mixtures with high content of two types of RA corresponding to extreme cases: the short-term aged RA (STA-RA), having a very soft residual binder (Pen > 20 dmm) and the long-term aged RA, having a much harder residual binder (Pen < 10 dmm). As a result, the proposed methodology allowed assessing the feasibility of using up to 90% of RA and determining whether the use of rejuvenating agents was needed.

Rheological, chemical and thermal investigations on an aged binder rejuvenated with two non-edible oils

The aged pavement material from a defunct pavement – commonly known as reclaimed asphalt pavement (RAP) – contains stiffened binder caused by loss of volatile materials and oxidation. Therefore, addition of a high amount of the RAP to asphalt mix, in case of pavement recycling, may make it prone to fatigue failure. Due to this reason, the addition of RAP to asphalt mixture in substantial amount has been a challenge so far. “Rejuvenators” are generally used to restore the properties of the aged binders in the recycled mixes. The present study deals with the assessment of two non-edible oils, that is, pongamia oil and composite castor oil (a composite rejuvenator having castor oil and coke-oven gas condensate) as asphalt rejuvenators to achieve 100% RAP recycling. The study mainly comprises rheological characterisation studies such as rutting behaviour, fatigue behaviour, dynamic mechanical analysis and creep-recovery studies of the rejuvenated binder specimens. Chemical investigations using infrared spectroscopy also affirmed use of these oils in effectively restoring the properties of aged binders. In addition, for assessment of the long-term performance in terms of thermostability of the rejuvenated binders, a thermal analysis was carried out using a simultaneous thermal analyser, which confirmed the adequate thermal stability of the rejuvenated binders. From the investigations taken up under this study, it was concluded that 5% oil (for both pongamia and composite castor oil) rejuvenated aged binder could show desirable rutting and fatigue behaviours and sometimes even better than the virgin binder. However, its confirmation can be laid only after suitable mix performance studies.

Multiscale imaging and characterization of the effect of mixing temperature on asphalt concrete containing recycled components.

When producing asphalt concrete mixture with high amounts of reclaimed asphalt pavement (RAP), the mixing temperature plays a significant role in the resulting spatial distribution of the components as well as on the quality of the resulting mixture, in terms of workability during mixing and compaction as well as in service mechanical properties. Asphalt concrete containing 50% RAP was investigated at mixing temperatures of 140, 160 and 180°C, using a multiscale approach. At the microscale, using energy dispersive X-ray spectroscopy the RAP binder film thickness was visualized and measured. It was shown that at higher mixing temperatures this film thickness was reduced. The reduction in film thickness can be attributed to the loss of volatiles as well as the mixing of RAP binder with virgin binder at higher temperatures. X-ray computer tomography was used to characterize statistically the distribution of the RAP and virgin aggregates geometric features: volume, width and shape anisotropy. In addition using X-ray computer tomography, the packing and spatial distribution of the RAP and virgin aggregates was characterized using the nearest neighbour metric. It was shown that mixing temperature may have a positive effect on the spatial distribution of the aggregates but did not affect the packing. The study shows a tendency for the RAP aggregates to be more likely distributed in clusters at lower mixing temperatures. At higher temperatures, they were more homogeneously distributed. This indicates a higher degree of blending both at microscale (binder film) and macroscale (spatial distribution) between RAP and virgin aggregates as a result of increasing mixing temperatures and the ability to quantify this using various imaging techniques.

Effects of RH-WMA additive on rheological properties of high amount reclaimed asphalt binders

Warm mix asphalt (WMA) additive enables the utilization of more reclaimed asphalt pavement (RAP) in road construction. However, variations in RAP properties complicate the characterization of the rheological properties of virgin binder when blended with reclaimed asphalt binder. This study presents the evaluation of rheological properties of reclaimed asphalt binder incorporating RH-WMA, a new wax based WMA additive. The reclaimed asphalt binders recovered from two road sources were blended at various percentages with 3% RH-WMA additive. The rheological evaluations were carried out from the viscosity and dynamic shear rheometer (DSR) test results. The results indicated that the incorporation of reclaimed asphalt binder into virgin binder increased the viscosity and stiffness, while addition of RH-WMA additive slightly reduced the viscosity and stiffness. A non-dimensional viscosity index indicated an increase in relative viscosity for every 1% reclaimed asphalt binder. The SHRP Rutting Parameter, rheological master curves and multiple stress creep and recovery (MSCR) test results showed consistency in terms of binder stiffness. An interesting finding on the elasticity improvement demonstrated by percent recovery due to the addition of RH-WMA additive in the MSCR test, indicated the possibilities of rutting improvement when utilizing RAP and RH-WMA additive.

Effect of aging on fatigue performance of hydrated lime modified bituminous mixes

Hydrated lime has traditionally been used as filler primarily for its ability to improve the moisture resistance of bituminous mixes. However, studies carried out in the past showed that the addition of hydrated lime is also useful in improving the resistance of bituminous mixes to rutting, fatigue and aging. The effect of lime in increasing the stiffness of the mix can be beneficial to thicker bituminous pavements, which will be in stress control mode of fatigue. The reduction in the rate of aging due to lime can also benefit the performance of mixes due to reduction in brittleness and improvement in the healing characteristics. The present work explores the effect of hydrated lime modification of bituminous mixes on their fatigue performance. The effect of two different methods of lime addition, wet and dry, was investigated. The influence of short-term and long-term aging of the mixes on the fatigue characteristics of bituminous mixes was examined. Ten different combinations of mixes with two virgin binders, four lime modified binders and four mixes with lime added as filler were considered in the investigation. The results of laboratory tests conducted for determination of the moduli of elasticity of mixes and the fatigue performance models obtained for different mixes, under two different aging conditions, combined with the mechanistic analysis of typical bituminous pavement sections established the beneficial effect of lime in improving the fatigue lives of bituminous layers, especially for thicker pavements.

Proposing a solvent-free approach to evaluate the properties of blended binders in asphalt mixes containing high quantities of reclaimed asphalt pavement and recycled asphalt shingles

Traditionally, the properties of blended binders in asphalt mixes containing reclaimed asphalt pavement (RAP) and recycled asphalt shingles (RAS) are evaluated through rheological testing of the binder extracted and recovered from a mix. However, this approach has long been criticized for being labor intensive, for potentially altering the chemistry of the binder and consequently changing the binder rheology, for forcing blending of binders that may not have been present in the mix, and for creating hazardous material disposal issues. The research presented in this paper proposes an alternative approach for characterizing blended binders by testing the linear viscoelastic properties of a fine aggregate matrix (FAM) asphalt mix using a torsion bar fixture in a dynamic shear rheometer (DSR). A procedure has been developed for preparation and testing of these FAM specimens. Based on the results from this preliminary study, FAM testing is considered to be an effective alternative approach to chemical binder extraction for characterizing the properties of blended binders, compatibility of virgin binders with RAP and RAS binders, and the influence of rejuvenating agents.

Binder rheological predictive models to evaluate rutting performance of asphalt mixtures

This study investigated the rutting performance of asphalt mixtures through prediction of resilient modulus (Mr) based on the binder rheological stiffness parameter: G∗/sinδ. A total of seven different asphalt binder types from three sources were used, including: (a) three viscosity grade virgin (VG-10, VG-30 and VG-40) binders; (b) two polymer-modified (PMB-40 and PMB-70); and (c) two crumb-rubber modified (CRMB-55 and CRMB-60) binders. A total of 860 data points were obtained for evaluation of G∗/sinδ and a predictive model as a function of binder viscosity. In order to correlate binder properties with that of the mixes, eleven asphalt mixtures with three sample replicates each were prepared: six dense graded with virgin binders; two gap-graded with polymer-modified binders; and three gap-graded rubber-modified binders. Mr test parameters were obtained for the mixtures at 15, 25, and 35°C and 0.5, 1, 1.5 and 2Hz covering 396 data points. A Mr predictive model based on G∗/sinδ stiffness parameter was established with excellent statistical goodness of fit measures. Finally, advanced viscoelastic Mr parameters were estimated and the viscoelastic indicators were correlated to binder stiffness parameter to assess rutting performance of asphalt mixtures. A novel attempt was made in this study that presents a promising approach to correlate asphalt binder and mixture performance by using only one single rheological parameter based on the DSR test: G∗/sinδ; so as to minimize the experimentation during binder and asphalt pavement material characterization in future.

A new laboratory methodology for optimization of mixture design of asphalt concrete containing reclaimed asphalt pavement material

The reduction of virgin bitumen added to asphalt mixtures containing Reclaimed Asphalt Pavement (RAP) is based on the typical assumption that all the aged binder function in the same way as the virgin binder. However, recent studies conducted by the authors for a specific case show that a blend or mobilization of RAP binder are negligible. The aged bitumen becomes softer acting as glue facilitating cluster formation between small-size RAP particles. The reduction of small-size particles causes changes in the target grading curve and in the voids-fill, affecting the compactability of RAP mixtures. Therefore the target grading curve of RAP mixtures needs to be readjusted, using different proportions of virgin aggregates and taking into account the cluster phenomenon. The objective of this paper is to develop a new mix design approach for RAP mixtures, taking into account the cluster phenomenon and the contribution of the aged bitumen in the compactability. The virgin aggregates, filler and RAP are investigated and individually included in the calculation. 3D images of the virgin aggregates allowed the determination of new surface area factors; the concept of critical filler concentration led to the definition of the minimum bitumen quantity required to maintain the mastic in a diluted state and fill the voids. A RAP clustering model was introduced to predict the agglomeration of small-size RAP particles. The readjustment of the target grading curve was analytically calculated, allowing the correct estimation of the amount of virgin bitumen to be added to asphalt mixtures. Finally, a first verification of the entire process was carried out performing laboratory tests. These promising results enable the challenge of a new mix design optimization for HMA with high RAP content to be addressed.

Characterizing the chemical and rheological properties of severely aged reclaimed asphalt pavement materials with high recycling rate

Frequent mill and overlay activities result in the production of a considerable amount of reclaimed asphalt pavement (RAP) materials. Many pavements that incorporated RAP exhibit a shorter service life than do those without RAP. One of the possible reasons is that certain RAP materials have already undergone multiple recycling processes during the past decade. This results in severe aging of the reclaimed asphalt binder (RAB). In this study, three severely aged RABs, two RAP blending scenarios, two virgin binders, and two commercial rejuvenators were used to investigate the feasibility of using severely aged binders for constructing pavements. The chemical and rheological properties of the rejuvenated severely aged binders were evaluated using high-performance gel permeation chromatography and a dynamic shear rheometer. The molecular size distributions of rejuvenated RABs revealed that the rejuvenators used in this study could rebalance the proportions of large, medium, and small molecular components among the rejuvenated RABs. However, the polydispersity values still enabled clearly distinguishing between virgin binders and rejuvenated RABs. Two performance parameters were used to evaluate the potential of age-induced damage as well as permanent rutting in the binders. A Glover–Rowe damage zone was evaluated, and it revealed promising results to distinguish among severely aged binders, virgin binders, and rejuvenated binders. Oscillation and multiple stress creep and recovery tests were performed to obtain rutting potential parameter G∗/sin(δ) and Jnr, respectively. The results indicated that all rejuvenated aged binders exhibited higher G∗/sin(δ) values and lower Jnr values compared with the control virgin binders.

Use of molecular dynamics to investigate diffusion between virgin and aged asphalt binders

The incorporation of recycled (aged) binder into virgin asphalt has become more popular in asphalt paving industry nowadays. However, the exact mechanism of the diffusion process between virgin and aged binders is still largely unclear. This paper presents a study in which molecular dynamics (MD) simulation was employed to investigate the diffusion between virgin and aged binders. Two asphaltic models with three components including asphaltenes, resin, and oil were built with different components ratio. The model of aged binder was constructed by increasing the asphaltenes ratio on the basis of virgin binder. The results of simulation was verified by GPC and both show that the diffusion of large molecules in asphalt was a critical factor for the diffusion of binders in that it was more susceptible to the changes of temperature. In an inter-diffusion model of virgin and aged binders, the diffusion coefficients of binders were not only determined by the diffusion ability itself, but also influenced by the properties of the diffusion acceptor. Based on this finding, the effect of different sequence of adding rejuvenator during recycling of asphalt mixtures was investigated. The result shows that adding rejuvenator into aged binder first could accelerate the inter-diffusion rate between virgin and aged binder in maximum level, thus increased the efficiency of recycling.

Investigation of Blending Mechanisms for Reclaimed Asphalt Pavement Binder and Virgin Binder in Laboratory-Produced Reclaimed Asphalt Pavement Mixtures

The use of reclaimed asphalt pavement (RAP) in new pavement construction or pavement rehabilitation projects contributes to sustainable construction. However, the blending between RAP binder and virgin binder could significantly affect pavement performance, especially in regard to cracking. Currently, studies to understand the different blending stages between RAP binder and virgin binder in a RAP mix and the effects of each blending stage on mix performance are lacking. In this study, three blending stages were investigated: Stage 1: RAP binder transfer to virgin aggregate, Stage 2: mechanical blending, and Stage 3: diffusion. The objectives of this study are to propose a laboratory mixing scheme to distinguish the effects of each of the three stages for blending between RAP binder and virgin binder; investigate the effects of each blending stage on the rheological and fracture performance properties of the study mixes; and identify the primary mechanisms of blending between RAP binder and virgin binder in laboratory-produced RAP mixtures. Tests, including dynamic modulus and creep compliance in indirect tensile (IDT) mode and IDT fracture tests at 20°C and −10°C, were conducted to determine the rheological and fracture properties of mixtures. Results indicated that at RAP binder replacement ratio of 26%, Stage 3 diffusion is the most dominant in affecting the rheological and fracture properties of RAP mixes compared with Stage 1 RAP binder transfer and Stage 2 mechanical blending.

Effect of Rejuvenators on Rheological, Chemical, and Aging Properties of Asphalt Binders Containing Recycled Binders

The use of reclaimed asphalt pavements (RAP) and recycled asphalt shingles (RAS) in pavements has already become a norm in the United States because of the substantial reduction in construction cost, energy consumption, and greenhouse gas emissions. However, highway agencies are still reluctant to increase the overall percentage of RAP and RAS in asphalt pavement mixtures because of a higher potential of premature cracking in these pavements. To avoid early pavement failures and untoward maintenance cost, rejuvenators are being increasingly used in asphalt mixtures to reconstruct the chemical structures of oxidized RAP and RAS binders. However, the overall effects of rejuvenators on the properties of asphalt binders have not been well studied in recent years and used in determining the optimum dosages for different rejuvenators. This study characterizes the effects of rejuvenators on the rheological, chemical, aging, rutting, and cracking properties of asphalt binders containing recycled binders and then uses the findings to recommend optimum dosages. To that end, PG 64-22 virgin binders were blended with different types of rejuvenators and recycled binders at various concentrations. Laboratory test results showed that rejuvenators could reduce the stiffness, oxidation, and cracking potential of these blends. Results also suggested that selecting the rejuvenator dosage and type on the basis of only one criterion could not meet the specifications of traditional virgin binders. In addition, the results showed that different rejuvenators worked differently with different mixtures.

Effect of Silo Storage Time on the Characteristics of Virgin and Reclaimed Asphalt Pavement Mixtures

Many hot-mix asphalt plants store material in heated silos before it is ready to be transported to construction sites. The time that material is stored in the silo is not controlled and varies widely, depending on several factors. As the material is exposed to elevated temperatures, short-term aging of the binder may occur. Another important consideration is the interaction between reclaimed asphalt pavement (RAP) and virgin binders, as blending or diffusion could occur between the binders. In this study, a virgin and 25% RAP mixture were sampled at incremental silo storage times up to 10 h. Characterization testing included performance grading, rheological indexes, Glover–Rowe parameter evaluation, rolling thin film oven aging on the binders, complex modulus, a simplified viscoelastic continuum damage model (S-VECD) for fatigue, and thermal stress restrained specimen testing of the mixtures. Simulations that used layered viscoelastic critical distresses pavement analysis to predict fatigue behavior from the S-VECD model were used to show the potential effects of silo storage time on pavement life. Results from all tests indicated that mixtures aged with an increase in silo storage time. RAP materials experienced a greater effect; this effect may be a function of the air void content or indication of blending–diffusion in the silo. Rolling thin film oven aging showed that current laboratory conditioning methods do not necessarily simulate asphalt plant production. Production parameters, such as silo storage time, have a significant impact on mixture performance.