Multiple Stress Creep Recovery Test Research Articles

Effect of waste crab shell powder on matrix asphalt

Abstract In order to solve the problems of depleting petroleum asphalt resources and deteriorating pollution of marine products, a systematic study was carried out on the application prospect of waste crab shell (WS) powder as asphalt modifier. In this study, the physical properties of WS powder modified asphalt (WSA) were tested by blending different contents of WS powder into matrix asphalt; the high and low temperature rheological properties of WS powder modified asphalt were characterized by using Dynamic shear rheometer, Bending beam rheometer, and Multiple stress creep recovery test. In addition, the microscopic chemical properties and modification mechanism were analyzed by Differential scanning calorimetry, Fourier transform infrared spectroscopy, Atomic force microscopy, and Scanning electron microscope. It was shown that the WS powder enhanced the viscoelastic properties, temperature sensitivity properties, and permanent deformation resistance of asphalt. In addition, there was no obvious chemical reaction between the WS powder and the matrix asphalt, and no new chemical substances were generated; at the microscopic level, the WS powder and the matrix asphalt had good compatibility. In conclusion, the use of WS powder as a bio-based asphalt modifier to improve the resources and environmental issues have certain prospects.

Extraction solvents effect on asphalt binder properties

Asphalt industries are actively pursuing the integration of recycled asphalt pavement (RAP) into their constructions to promote sustainable pavement solutions amidst resource scarcity. However, challenges persist in the extraction and recovery processes, potentially affecting asphalt pavement performance assessments. This study investigates the impact of three common solvents—n-propyl bromide (nPB), trichloroethylene (TCE), and a toluene-ethanol blend (85 %/15 %)—on the rheological properties of recovered binders, particularly aiming to identify a substitute for TCE in light of its proposed ban by the Environmental Protection Agency (EPA) in the USA. Tests were conducted on six different performance-graded (PG) binders from diverse sources, assessing high-temperature properties using Dynamic Shear Rheometer (DSR) and Multiple Stress Creep Recovery (MSCR) tests, as well as low-temperature properties via Bending Beam Rheometer (BBR). Fourier Transform Infrared (FTIR) spectroscopy confirmed the absence of solvents in the recovered binders. Although minor variations were observed in measured properties between original and recovered binders due to solvent use, these differences did not affect the resulting performance grades. Thus, the toluene-ethanol blend can potentially substitute for TCE. However, it is noteworthy that the toluene-ethanol blend (85 %/15 %) displayed a slower solubility rate compared to nPB and TCE, underscoring the need for caution in its usage.

Exploring the physicochemical and rheological properties of sustainable asphalt binders modified with lignin and high-viscosity additive

The primary objective of this investigation is to evaluate how the incorporation of lignin and high-viscosity modifiers impacts the performance of asphalt binders. Lignin-modified asphalt binder (LBA) and lignin-high viscosity modifier composite-modified asphalt binder (LHA) were created by blending 5 % and 15 % lignin, respectively. To understand the physicochemical interactions, Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) were employed to analyze functional groups, thermal properties, and phase changes. Additionally, the linear rheological behavior and nonlinear rheological behavior were evaluated through frequency sweep and multiple stress creep recovery tests. The findings suggest that lignin blends physically with the asphalt binder and high-viscosity modifier without a chemical reaction. Although the onset pyrolysis temperature of lignin is significantly lower than that of asphalt binders, due to its relatively low content, the thermal decomposition of lignin-modified asphalt binders is primarily controlled by the asphalt binder itself and still exceeds the construction temperature. However, lignin incorporation increases the asphalt binder's glass transition temperature, potentially affecting low-temperature performance. Lignin significantly enhances the modulus in the high-frequency region of both unmodified and high-viscosity modified asphalt binder. However, it has a negative effect on the modulus in the low-frequency region of high-viscosity modified asphalt binder. Furthermore, nonlinear creep recovery test results demonstrate that lignin positively contributes to the deformation resistance of unmodified asphalt binder in a content-dependent manner, whereas it reduces the elastic behavior and deformation resistance of high-viscosity modified asphalt binder. In addition, low levels of lignin increase the stress sensitivity of binders, while high levels of lignin decrease it. Despite these effects, the performance of lignin and high-viscosity additive composite-modified asphalt binder remains superior to that of unmodified asphalt binder. These findings offer valuable insights into the combined use of lignin and polymers in asphalt binder modification.

Development of SBS composite modified asphalt incorporating polydopamine-enhanced MoS2

This study investigated the development of a novel composite modified asphalt incorporating PDA-MoS2 into styrene-butadiene-styrene (SBS) modified asphalt. The successful synthesis of PDA-MoS2 was confirmed through various characterization techniques. The incorporation of PDA-MoS2 into SBS modified asphalt resulted in significant improvements in performance properties. With a PDA-MoS2 content of 0.7 wt%, the modified asphalt showed a notable 15.1% rise in softening point and a 24% drop in penetration in comparison to the control SBS modified asphalt. Dynamic Shear Rheometer tests revealed a 2.4-fold increase in the rutting factor at 60°C. Multiple Stress Creep Recovery tests demonstrated enhanced rutting resistance, with a 72.2% reduction in nonrecoverable creep compliance at 0.1 kPa stress level. Electrochemical measurements showed improved corrosion resistance, evidenced by lower current densities and higher charge transfer resistance. Microstructural analysis revealed well-dispersed PDA-MoS2 particles forming a compact network structure within the asphalt matrix. The hydrophilicity of the modified asphalt increased, with a 35.3% decrease in water contact angle. The synergistic effect between PDA-MoS2, SBS, and asphalt components, facilitated by enhanced interfacial interactions and chemical bonding, contributed to the observed performance improvements. The results indicate that PDA-MoS2 has the potential to improve the characteristics of SBS modified asphalt as a modifier.

Evaluation and comparison for higher temperature performance index of emulsified asphalt mastic using coal gangue powder

In order to investigate the rheological behavior and the influence of solid waste coal gangue powder on the high-temperature performance of cold recycled Emulsified Asphalt Mastics (EAM), Dynamic Shear Rheometer (DSR) and Multiple Stress Creep Recovery (MSCR) tests were conducted using three different fillers and four powder-to-binder ratios of EAM. Evaluation indexes such as rutting factor (G*/sinδ), improved rutting factor (G*/1−1/sinδ∙tanδ), Unrecoverable Creep Compliance (Jnr), Cumulative Strain (CS) and Creep Recovery Ratio (R) were used to analyze the influence of filler type and dosage on high temperature of EAM, and the effectiveness of these indexes to evaluate high temperature is considered. Moreover, atomic force microscopy experiments were carried out to study on interaction mechanism between the fillers and emulsified asphalt. Finally, grey relational analysis method was used for quantitative assessment of these indexes for EAM. The results indicate that all three fillers effectively improve the high-temperature performance, with a larger improvement observed as the filler dosage increases, among which the tunneling coal gangue powder is the most significant. Under a stress level of 0.1 KPa, the coal gangue filler mastic appears the best deformation recovery ability, whereas under a stress level of 3.2 KPa, the cement filler mastics appears the best deformation recovery ability. The additional fillers significantly influence the nano-scale surface morphology of the residues, and the tunneling coal gangue powder appears a stronger adsorption capacity for free polar components compared to the cement and limestone mineral powder. It is suggested that the Jnr and CS can be used as evaluation indexes of high temperature evaluation index of EAM, instead of G*/1−1/sinδ∙tanδ or G*/sinδ or R.

Performance Characterization of the Field Aged Asphalt Pavement Materials at Mortar Scale: Testing Method Optimization and Rheology Analysis

Performance evaluation at the asphalt mortar scale offers increased sensitivity to aging and is less affected by extraction processes comparated to asphalt mixture. Despite these benefits, there is currently a lack of standardized methods for directly processing mortar samples obtained from field mixtures. This study aims to improve and validate a manufacturing procedure for aged mortar specimens derived from field aging cores, and to evaluate the field damage level of asphalt paving materials at the mortar scale. A novel approach was developed that incorporates warm sieving, compaction, coring, and cutting to manufacture mortar specimens suitable for Dynamic Shear Rheometer (DSR) tests. This study selected mortar specimens with different service ages and conducted rheological tests, including frequency sweep tests and modified Multiple Stress Creep Recovery (MSCR) tests, to assess their rheological performance. And the significance test of all the indcies were conducted to select suitable indcies.The results show the proposed aged mortar manufacture approach can prepare eligible mortar specimens for rheology tests. The rheology test results show that several indices can distinguish different mortar types and service ages, and the indices of surface layer mortar follow a linear relationship with service age. The linear viscoelastic zone (LVE), representative shear modulus (G0), and unrecovered creep compliance at 1.6kPa (Jnr1.6) and 3.2kPa (Jnr3.2) are identified as effective indices for evaluating the behavior of field aged mortar because of their effectiveness, lower variability, and better distinction.

Rheological and Aging Properties of Nano-Clay/SBS Composite-Modified Asphalt.

Nano-organic montmorillonite (OMMT) not only inhibits the harmful asphalt fume generation during the production and construction processes of asphalt mixtures but also effectively improves the performance of asphalt pavements. In order to prepare asphalt materials with smoke suppression effects and good road performance, this study selects nano-OMMT and SBS-modified asphalt for composite modification of asphalt mixtures and systematically investigates its road performance. Through the temperature sweep test, the frequency sweep test, the multiple stress creep recovery (MSCR) test, the bending beam rheometer (BBR) test, and the atomic force microscope (AFM) test, the high-temperature rheological properties, low-temperature rheological properties, high-temperature properties and aging resistance of the modified asphalt are studied. The research findings indicate that OMMT can effectively reduce the sensitivity of modified asphalt to load stress and improve its high-temperature rheological properties. SBS-modified asphalt shows increased creep stiffness and a decreased creep rate after OMMT modification, resulting in reduced flexibility and decreased low-temperature crack resistance. After short-term and long-term aging, the complex modulus aging index of OMMT/SBS composite-modified asphalt is lower than that of SBS-modified asphalt, and the phase angle aging index is higher than that of SBS-modified asphalt, demonstrating that OMMT enhances the aging resistance of SBS-modified asphalt. OMMT inhibits oxidation reactions in the asphalt matrix, reducing the formation of C=O and S=O bonds, thereby slowing down the aging process of modified asphalt and improving its aging resistance.

Study on the Storage Stability and Rheological Property of Bio-Oil/Lignin Composite-Modified Asphalt.

The objective of this study is to investigate the storage stability and rheological property of bio-oil/lignin composite-modified asphalt. The composite-modified asphalt with different proportions of bio-oil was prepared and cured at 105 °C, 135 °C, and 165 °C for 24 h and 48 h. The storage stability of the composite-modified asphalt was evaluated based on the softening point difference, the storage stability index derived from rotational viscosity, the segregation rate based on temperature sweep, and the non-recoverable creep compliance measured through the Multiple Stress Creep Recovery test. The storage stability of bio-oil/lignin composite-modified asphalt was evaluated through testing and analysis of its infrared spectroscopy and scanning electron microscopy before and after thermal storage. The research results indicate that the maximum difference in softening point is 0.9 °C, and the calculated storage stability index is generally below 0.1. The maximum value of the segregation rate is 0.43, indicating excellent storage stability of the bio-oil/lignin composite-modified asphalt. According to the results from infrared spectroscopy, no chemical reactions occurred during the storage process of the composite-modified asphalt. The scanning electron microscope confirmed that the samples became more stable after 48 h of storage.

Unveiling the composite rejuvenator efficacy on performance improvement of asphalt binder including high RAP contents

Since the incompatibility between crumb rubber (CR) and reclaimed asphalt binder (RAB) can cause sedimentation and limit its application, this study employed waste cooking oil (WCO) to pre-treat CR particles at different CR/WCO ratios, and assessed its impact on performance of asphalt binders including 30 % and 50 % RABs. Anti-aging and rejuvenation potentials of corresponding composite rejuvenators in binder blends were explored by Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC) tests, while the performance of corresponding binder blends was evaluated by bending beam rheometer (BBR), linear amplitude sweep (LAS), and multiple stress creep recovery (MSCR) tests. Furthermore, correlation analyses were performed to explore the relationships between the chemical and rheological parameters with a significance level below 0.05. The results confirmed the rejuvenation efficacy of composite rejuvenators in high RAB, and improvement in the critical low temperature of binder blends to a higher performance grade (PG) level compared to the non-treated CR modified binder. In addition, the fatigue cracking resistance was improved at the strain levels higher than 4 % in LAS test. However, the pre-swelled CR fairly compromised the rutting performance of binder blends compared to non-treated CR, its performance was still better than virgin binder. The correlation analysis suggested that it is possible to use chemical parameters as indicators for evaluating certain rheological properties.

Enhancing fiber-reinforced asphalt binders via graphene oxide grafting: A novel interfacial modulation strategy

This study reports a novel interfacial enhancement strategy for fiber-reinforced asphalt binders. The graphene oxide (GO) nanosheets were used and grafted onto polyester (PET) and polyacrylonitrile (PAN) fibers in order to enhance the performance of modified asphalt binders. Prior to this, ultraviolet ozone (UVO) treatment was primarily adopted for activating the inert surface of fibers. Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and Scanning electron microscope (SEM) confirmed that GO-modified fibers were successfully prepared via surface modification. For the rheological properties determined by dynamic shear rheometer (DSR), the asphalt binders with GO-modified fibers exhibit improved high-temperature rutting resistance, better creep and recovery characteristics and increased anti-fatigue properties. Remarkably, it demonstrates that the recovery (R) value of GO-PAN modified asphalt binder is increased by 21.9 %, and the non-recoverable compliance (Jnr) value of GO-PET modified asphalt binder has been reduced by 31.9 % compared to that reinforced with the unmodified fiber in multiple stress creep recovery (MSCR) tests. These enhancements are mainly attributed to the increased roughness and modulus of the GO-grafted fibers, which promote effective stress transfer at the fiber-asphalt interfaces. Results from the atomic force microscope (AFM) indicate that the Young’s modulus of GO-PET and GO-PAN is 94.2 % and 260.0 % higher than that of PET and PAN, respectively. This research not only provides a simple and cost-effective method for improving the rheological performance, but also elucidates the enhancement mechanism of interfacial behavior in fiber-reinforced asphalt binders.

Effect of nano-modified EVA on the physical and rheological characteristics of SBR modified asphalt binder

The effects of nanoclay-modified ethylene-vinyl acetate (MEVA) on the physical and rheological properties of styrene–butadiene–rubber (SBR)-modified asphalt binder were investigated. MEVA/SBR composite-modified asphalt binders (MESBR) were prepared with 4 % SBR and varying MEVA content. The effect of MEVA on the properties of SBR-modified asphalt binder (SBRMA) was investigated through penetration, softening point, ductility, viscosity, temperature sweep, and frequency sweep tests. Furthermore, multiple stress creep recovery and bending beam rheometer tests were performed to analyse the deformation resistance and low-temperature performance of MESBR. Additionally, the storage stability of MESBR was evaluated through separation tests and fluorescence microscopy. The results indicated that MEVA addition significantly enhanced the physical and rheological properties of SBRMA both before and after ageing. Compared with SBRMA, MESBR exhibited improved deformation and ageing resistance, making it suitable for use under standard traffic loads at temperatures up to 76℃. However, MEVA exhibited a slightly negative impact on the low-temperature performance and storage stability of MESBR. With the addition of 5 % MEVA, MESBR exhibited favourable comprehensive performance and good storage stability.

Comprehensive rheological and mechanistic evaluation of an asphalt binder and mixture modified with warm mix additives.

Though warm mix asphalt (WMA) technology has been introduced for a long time, there is still reluctance in the industry to utilize it in practice. In regions like India, where WMA incorporation into road construction has been limited over the past two decades, building confidence in local binders is imperative for widespread adoption. Thus, the present study appraises the effect of three commonly used WMA additives in India, namely Sasobit®, Evotherm®, and Zycotherm®, with base binder VG-30 on the rheological and mixture performance parameters. Three dosages of each WMA additive were blended with the control binder to give ten binder combinations. Different binder evaluations such as Superpave grading and parameters, frequency sweep testing, multiple stress creep recovery test, and linear amplitude sweep test were conducted for comparative dynamic mechanical analysis. Based on the binder testing results, suitable dosages of WMA additives were established, and mixture testing was carried out using these specific additive dosages. Binder evaluations showed improvement in high-temperature characteristics with Sasobit® and better fatigue performance with Evotherm®, while Zycotherm® did not alter binder properties significantly. The asphalt mixture testing results indicated satisfactory performance with the three additives based on Marshall stability and flow testing. The WMA additives also showed enhancement in moisture susceptibility based on the modified Lottman test with Zycotherm® demonstrating the best performance. Overall, the study underscores promising effects of the three WMA additives across different parameters, signaling their potential for widespread application in real-world scenarios.

The investigation of rheological properties of rejuvenated asphalt binder with waste cooking oil as rejuvenator

Asphalt binder plays a significant role in the performance of asphalt pavement. However, due to the limited availability of crude oil and the increasing cost of asphalt, alternatives are being investigated. Reclaimed asphalt pavements (RAP) provide a sustainable solution for the increasing demand of asphalt. However, the amount of RAP which can be utilized in asphalt mixtures is limited due to production and performance issues. Incorporation of high RAP content calls for rejuvenators, which rejuvenate the aged binder and increases the degree of blending. Among various rejuvenators, waste cooking oil (WCO) is gaining increased attention due to its availability and concern towards environmental pollution. When combined in proper proportions with RAP, WCO is a potential rejuvenator, which restores the properties of aged binder to that of unaged asphalt binder. This addresses two problems simultaneously and can greatly benefit the economy and environment. This study focuses on the viscoelastic and rheological properties of the rejuvenated binder with WCO and RAP. The rheological properties are evaluated using frequency sweep test by assessing the complex shear modulus and rutting parameter of different binders. The viscoelastic properties are studied using multiple stress creep recovery (MSCR) test. The data of the MSCR test is analysed with the Burger model to understand the viscoelastic properties of the rejuvenated RAP binder. For each of 75, 60 and 45% RAP, three different oil proportions are selected, and the optimum WCO content is identified. The study concludes that higher RAP content results in lower viscous strain and higher elastic strain, whereas after mixing of higher WCO, the viscous strain increases, and elastic strain decreases. Hence, it is crucial to mix WCO and RAP in the optimum ratio to obtain the desired rheological and viscoelastic properties.

Rheological behaviour of modified binders for different loading conditions and temperatures: A case of using pig tallow and crumb rubber from end–of–life tyres

This study investigates alternatives to Styrene-Butadiene-Styrene (SBS) polymer in asphalt mixtures by evaluating End-Of-Life tire (ELT) crumb rubber (CR) and fatty acid amide wax (FAA) derived from pig tallow. The research focuses on triple modification of binders with SBS, ELT and FAA to improve performance and reuse waste and industrial by-products in an economical and environmentally responsible manner. The results show that the incorporation of ELT and FAA significantly reduces the SBS content, achieving a 73 % improvement in elastic performance according to Multiple Stress Creep Recovery (MSCR) tests. In addition, this combination improves peak stress and fatigue life in Linear Amplitude Sweep (LAS) tests, demonstrating potential benefits in asphalt mixtures. The study concludes that the combination of pig tallow and end-of-life tire materials doubles the yield energy (Yield Energy of Asphalt Binders, BYET) compared to samples with higher SBS content. In particular, a modification with 6 % CR, 3 % SBS and 2 % FAA doubles the toughness (Er) of a binder with 5 % SBS. This contributes to higher tensile strength in asphalt mixtures, promoting sustainability and efficiency in the road construction industry. This study provides a deeper understanding of how the combination of ELT, FAA and SBS can optimize the properties of asphalt mixtures, highlighting the potential of these additives to improve performance, reduce costs and minimize environmental impact.

Laboratory evaluation of performances and thermo-oxidative aging characteristics of high-viscosity modified asphalt

High construction temperatures and complex application conditions make the high-viscosity modified asphalt (HVMA) susceptible to aging. This work presents a comprehensive investigation of the performances and thermo-oxidative aging characteristics of HVMA. Fistly, an instant high-viscosity modifier (HVM) was synthesized and then optimized by entropy weight method. The modification mechanism and high- and low-temperature performances of HVMAs were investigated by the Fourier transform infrared spectroscopy (FTIR), temperature sweep, and low temperature creep tests. Besides, thermo-oxidative aging characteristics were evaluated by the frequency sweep, multiple stress creep recovery (MSCR) and fluorescence microscopy (FM) tests. Results shows that the recommended formulation of instant HVMA (HVMA-I) was 12 % instant HVM and 0.2 % stabilizer. Grafting and cross-linking reactions involved in HVMA-I, thus ensuring the excellent high- and low-temperature performances. The thermo-oxidative aging of HVMA consisted of the modifier degradation and the binder oxidation. Short-term aging produced a marginal effect as a fluctuating change direction for complex modulus. Long-term aging had pronounced effects on the performances of HVMA. At the macroscopic level, the complex modulus was increased and the nonrecoverable creep compliance was decreased; at the microscopic level, the fluorescence area was reduced and phase network was degraded.

Rheological and microscopic characterization and correlation analysis of asphalt under high-intensity ultraviolet radiation

The lower radiation intensity (2–20 W/m2) was widely used for asphalt ultraviolet (UV) aging. The effect of high-intensity radiation on asphalt properties and microscopic morphology is unknown. This study investigated the rheological behavior, microscopic characterization, and correlation analysis of SBS modified asphalt under high-intensity UV radiation. Rheological properties tests encompassed temperature sweep (TS), multiple stress creep recovery (MSCR), and frequency sweep (FS). Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and Gel Permeation Chromatography (GPC) tests were performed to reveal the microscopic characterization. In the early stages of UV aging, the rutting factor of asphalt was increased. The increment decreased as the UV aging time increased. The UV aging process did not alter the temperature sensitivity of asphalt. The complex shear modulus was influenced by UV radiation duration and loading frequency. Extended exposure to high-intensity UV radiation resulted in the formation of microcracks on the surface of the asphalt. The maximum molecular weight of the UV-aged asphalt was higher than that of the original asphalt. The degraded SBS modifier deteriorated the homogeneity of asphalt. The sulfoxide aging index, carbonyl aging index, number-average molecular weight (Mn), weight average molecular weight (Mw), and polymer dispersity index (PDI) presented a better correlation with rheological behavior indexes. The correlation between small molecule size (SMS), medium molecule size (MMS), and large molecule size (LMS) with rutting factor and complex shear modulus was poor. It was worth mentioning that the correlation between the MSCR test results and microscopic performance indicators was the best. Especially for the recovery rate and Jnr at 3.2 kPa, the mean absolute value of the correlation coefficient was 0.953.

Performance Evaluation and Modification Mechanism Analysis of High-Viscosity Modified Asphalt

Abstract High-viscosity modified asphalt (HVMA) has important application potential in pavement engineering, such as porous asphalt pavements and ultrathin overlays. To comprehensively study and evaluate the overall performance of HVMA, five HVMA samples were prepared using modifier with dosages of 6 %, 9 %, 12 %, 15 %, and 18 %, respectively. The basic physical properties of HVMA were evaluated according to standard physical asphalt performance tests. The overall rheological properties of HVMA were assessed using temperature sweep tests, frequency sweep tests, and multiple stress creep recovery tests. Fluorescence microscopy was employed to analyze the microscopic characteristics and the modification mechanism of HVMA. The results show that the high-viscosity modifier could improve the overall rheological properties of HVMA at both high and low temperatures, with approximately 9 % determined as the optimal dosage. HVMA had better performance than matrix asphalt in high-temperature rutting resistance, permanent deformation resistance, temperature sensitivity, and elastic characteristics. At an appropriate dosage of the high-viscosity modifier, the modifier absorbed the light components in the asphalt, causing them to swell and dissolve. As a result, the modifier could be uniformly dispersed in the asphalt, thereby significantly improving the high-temperature stability of HVMA. The results of this paper may be helpful to the mechanism research and application of HVMA.

Comparative analysis of several short-term aging simulation methods and their impact on long-term aging performance of asphalt binders

The aging of the asphalt pavement is an essential factor to consider when constructing a road. Several methods, such as the Thin Film Oven Test (TFOT) and Rolling Thin Film Oven Test (RTFOT), have been used to simulate the short-term aging of asphalt binders. Based on the wide use of polymer-modified asphalt binder and the idea of research facilitation, 5 hours of Pressure Aging Vessel (5 h PAV) was proposed as an alternative to previous short-term aging methods of asphalt binders. However, the efficacy of this technique still needs to be wholly explored in all aspects and requires advanced research. The frequency sweep, temperature sweep, and Multiple Stress Creep Recovery tests were performed to evaluate the high-temperature performance of asphalt binders under aging conditions. In addition, the relaxation test was carried out to determine the low-temperature stress relaxation change and the fatigue cracking resistance of asphalt binders. The Chemical test explored the chemical change of asphalt binders under different aging conditions. The findings revealed that, in the case of neat asphalt binders N50, N70, and N90, the maximum disparity between the aging conditions of TFOT and 5 h PAV was found to be below 6 %. However, the difference between the aging conditions of 5 h PAV and RTFOT was observed to be approximately 20 %. Then, 5 h PAV can be highly recommended as an alternative to replacing TFOT. For SBS and high viscosity-modified asphalt binders HVMA-I and HVMA-II, the maximum gap between 5 h PAV and TFOT was estimated to be approximately 19.71 %. However, the gap between 5 h PAV and RTFOT was estimated to be less than 7 %. Then, 5 h PAV can be an alternative to replace RTFOT for modified asphalt binders if necessary. This study offers a thorough explanation and dispels doubts regarding the suitability of the 5-hour PAV as an alternative for simulating the short-term aging of asphalt binders, thereby enhancing research facilitation. Furthermore, the research delineates the impact of various short-term aging simulation methods on the long-term aging properties of asphalt binders, including the variation rates between them.

Asphalt binder modified with high density polyethylene: 2S2P1D rheological modelling and damage characterization

ABSTRACT The new needs in the paving industry have led to the intensification of the use of modified binders, and the use of plastics (non-biodegradable waste) can be an ally in facing both environmental and technical challenges. This study evaluated the feasibility of modifying a conventional asphalt binder with high density polyethylene (HDPE) at contents of 1, 3 and 5% for performance improvement, using rheological and performance tests. The linear viscoelastic properties were obtained by the temperature-frequency sweep test, and for the first time the 2S2P1D rheological model was used to describe these data for an HDPE-modified binder. Resistance to permanent deformation and fatigue was verified by the Multiple Stress Creep Recovery (MSCR) and Linear Amplitude Sweep (LAS) tests, respectively. The Fatigue Factor of Binder was obtained at 3 levels of strain for the first time for this material. HDPE made the material stiffer and more elastic observed by the coefficients of the 2S2P1D model. The modification resulted in better performance regarding permanent deformation and in general had an impact of less than 10% on the fatigue life of the material. Thus, it is possible to state that HDPE can be incorporated into the asphalt binder without harming its performance.

Analysis of Rutting Behaviour of Recycled Asphalt Binder and Rejuvenated Recycled Asphalt Binder by Multiple Stress Creep Recovery (MSCR) Test

Analysis of Rutting Behaviour of Recycled Asphalt Binder and Rejuvenated Recycled Asphalt Binder by Multiple Stress Creep Recovery (MSCR) Test