Asphalt Materials Research Articles

Research on asphalt materials based on machine vision and generate adversarial networks

With the rapid development of artificial intelligence and deep learning, computer vision-oriented generative models have been widely used. Among them, the generation of adversarial network has the most far-reaching influence. To solve the problem of dynamic instability in the training of generative adversarial networks, this paper proposes a rapid construction method of generative adversarial networks based on hidden layer characterization. The generation process of the adversarial network is divided into two independent generation processes to generate the representation of the experience hidden layer and the final result respectively, so as to stably generate the training dynamics of the adversarial network and capture more data patterns. This method can effectively and stably generate the training dynamics of the adversarial network. Finally, theoretical analysis proves that this method can stably generate the training dynamics of adversarial network and reduce the difficulty of adversarial training. Large-scale experiments on multiple data sets demonstrate the effectiveness of the proposed method.

Modeling of Fatigue Cracking in Asphalt Materials Based on the Paris Law with an Initialization Term—Calibration from Notched and Unnotched Specimens

Abstract This article aims at presenting a thermo-mechanical model dedicated to fatigue cracking in bituminous material. The model calibration based on two-point bending (2PB) fatigue tests performed on specimens of bitumen-bound sand is also detailed. In the model, crack growth is handled by the Paris law considering the initialization term Nini. This parameter represents the number of loading cycles required to initiate a short macrocrack of length a0 from which the Paris law can be applied. The tests utilized for calibration and comparison with the numerical simulations are performed on notched and unnotched trapezoidal samples, for different levels of imposed displacement amplitude. The parameters of the Paris law are determined using the notched specimens (a0 being assimilated to the notch depth) except for Nini, which is deduced from the difference in lifetime duration between the tests carried out on notched and unnotched specimens. The full calibration procedure described thereafter has the advantage to not depend on the choice of a0. It is shown that the simulations run for the calibrated model are globally in good agreement with the test results obtained for both types of samples and for all the imposed displacement amplitudes. Finally, the model is used to predict the response of four-point bending tests carried out on the same bitumen-bound sand, considering the input parameters determined from the 2PB tests. The intrinsic nature of the model is evaluated through its ability to simulate both types of tests using the same set of material parameters.

Study on properties of graphene-SBS double-modified asphalt

In this paper, different proportions of graphene modifiers were used to double-modify the SBS-modified asphalt. The needle penetration, softening point, and ductility of modified asphalt with different proportions of graphene incorporation were measured by the national standard test method. As affected by adding different proportions of graphene on the three indexes of SBS modified asphalt was studied. Through the analysis and comparison of the experimental results, when the graphene parameter is 0.5%, the performance of graphene-SBS double-modified asphalt reaches the optimum, which provides technical reference for the diversification of modified asphalt materials in the alpine region of Inner Mongolia.

Multiscale Characterization of Rejuvenated RAP Binders

Abstract Reclaimed asphalt pavement (RAP) is increasingly being utilized in asphalt pavements because of the high cost and scarcity of virgin asphalt materials. However, because RAP is a stiff material, it requires careful engineering to prevent cracking. Recycling agents have shown the ability to partially restore the properties of RAP binders if applied in a proper type and dose. Many studies investigated the impact of recycling agents when added to blends of virgin and RAP binders, but only a few investigated their effectiveness when applied to only RAP binders. The aim of this paper is to investigate the effect of various types and doses of recycling agents on the properties of RAP binders. Rheological properties were measured using a dynamic shear rheometer (DSR). Fourier-transform infrared spectroscopy was utilized to measure the degree of oxidation of the rejuvenated RAP binders. Furthermore, atomic force microscopy (AFM) tests were conducted to measure the morphology and modulus of rejuvenated RAP binders at the nanoscale. Finally, AFM measurements were used to calculate a rejuvenation index (RI), which was developed in an earlier study by the authors to assess the effectiveness of recycling agents in resisting the adverse effects of aging. DSR results demonstrated that the inclusion of recycling agents lowered the stiffness of the RAP binders. AFM morphology images revealed the presence of a large number and varying sizes of phase associations in the RAP binders. These phase associations became more pronounced with aging. Some recycling agents partially reversed the aging effect by reducing the area occupied by these associations. Nonetheless, after long-term aging, the effect of recycling agents diminished. The results of this study revealed that characterizing rejuvenated RAP binders at both the microscale and macroscale levels can indicate the effectiveness of recycling agents and aid in the selection of type or dose of recycling agent.

The Effect of Incorporating 100% of Undiluted and Diluted Reclaimed Epoxy Asphalt Materials into Pervious Cement Mixes

In order to improve the sustainability of road pavements, transportation agencies should consider designing pavements with recycled materials such as reclaimed epoxy asphalt pavement. Epoxy asphalt has recently attracted significant attention from the pavement community as a superior-performing binder that can help achieve long-lasting pavements. The recyclability of a proven long-life pavement material, such as epoxy asphalt, has now become one concern in promoting the use of epoxy asphalt binder in road pavements. Due to its thermosetting nature, the usual process of reclaiming asphalt pavement cannot be performed on epoxy asphalt pavement. Recent studies have investigated utilizing reclaimed epoxy asphalt materials in asphalt mixtures as black rock. In light of this, examining the use of reclaimed epoxy materials in cement-concrete mixes is important. The use of reclaimed epoxy asphalt materials in pavement construction is expected to gain more popularity and become a new sustainable construction option in various sustainable pavement applications in the near future. The main objective of this study is to investigate the effects of incorporating 100% reclaimed epoxy asphalt (hereinafter referred to as “epoxy RAP”) and reclaimed diluted epoxy asphalt materials (hereinafter referred to as “diluted epoxy RAP”) into cement-concrete mixes on the performance of the mixtures. The study also examined the effects of replacing cement with 5% silica fume on the performance of reclaimed mixtures. Five different mixtures were fabricated and tested in terms of density, void content, permeability, and compressive strength. Results of the density test revealed that replacing 100% natural aggregates with epoxy RAP and diluted epoxy RAP materials reduced density by an average of 10%. However, void content was found to increase with the incorporation of epoxy RAP, even when replacing Portland cement with silica fume. Regarding permeability, mixtures containing 100% epoxy RAP and diluted epoxy RAP materials have significantly higher permeability values compared with the natural mix value. However, adding 5% silica fume significantly reduced the permeability. Compressive test results indicated that substituting 100% of aggregates with epoxy RAP or diluted epoxy RAP materials would reduce compressive strength by 55% on average. Furthermore, adding silica fume to reclaimed mixes was found to have no apparent effect on compressive strength.

Characterization of the fatigue behavior of asphalt binders, FAMs, and AC mixtures based on multiscale approaches and the S-VECD model

Although investigations on upscaling methodologies across binder, Fine Aggregate Matrix (FAM), and Asphalt Concrete (AC) have been reported in the literature, additional evaluations should be performed considering the characteristics of the materials. This study investigates the relationship between the fatigue damage behavior of asphaltic material constituents based on a correlational assessment, as well as on experimental and analytical approaches. For that, rheological properties of asphalt binders were determined and AC and FAM were characterized by uniaxial tests. The fatigue parameters presented strong correlations across the scales and upscaling experimental equations were obtained from experimental data with good and promising results.

Evaluating the effects of oxidation and the deagglomerating potential of selected additives on asphaltene aggregation via computational modeling

Economic and environmental sustainability has been a significant stimulus to the use of recycled asphalt materials in the pavement industry. In this practice, rejuvenators are usually required to treat the oxidized asphalts with the aim to restore the physical properties and engineering performance. A critical function required for rejuvenators is that they can deagglomerate the asphaltene aggregates by effectively interacting with them. This study employed the techniques of molecular dynamics simulations and quantum chemical calculations, and investigated the impacts of oxidation on asphaltenes and the deagglomerating potential of three selected additives with different molecular structures and polarities, i.e., tributyl citrate (TBC), limonene, and myristamide. Analyses based on the aggregation number, orientational order parameter, and decomposition of the interaction energy indicated that oxidation strengthened the binding between the asphaltenes and thus promoted their aggregation behaviors. Among the three additives, TBC exhibited the highest rejuvenating effectiveness as it restrained the formation of large asphaltene aggregates and improved the orientational randomness of the aromatic cores. This capability was attributed to the highest number of polar sites in TBC and its three-dimensional spatial structure, which enhanced the compatibility and interactions with the aged asphaltenes. Based on the independent gradient model (IGM) method, the asphaltene aggregation is driven by the π-π interactions dominated by dispersion forces between the fused aromatic cores. The additives weakened the asphaltene interactions to different degrees, but the reversing effects were limited compared to the unaged state.

Research Progress of Epoxy Asphalt Material for Roads

Asphalt is a semi-solid or solid mixture formed by hydrocarbons and non-metallic elements. It is widely applied in the fields of building waterproofing and road paving. Asphalt is a low noise, durable, and renewable pavement material. However, asphalt materials have some shortcomings such as liquefying at high temperatures and brittleness at low temperatures, which are less adaptable to different environments. Therefore, people have gradually shifted their focus to asphalt modification. This paper presents an in-depth analysis and research on the composition, structure, and performance of epoxy asphalt materials for roads, so that this material can be widely used.

Molecular dynamics study on improvement effect of polyethylene terephthalate on adhesive properties of asphalt and cement-based composite interface

ABSTRACT Revealing the bonding mechanism between asphalt and cement-based materials is crucial for understanding the strength formation of semi-flexible pavement (SFP) materials and improving the performance indicators of SFP roads. Based on molecular dynamics simulation, the interface models of calcium silicate hydrogel (C-S-H) with virgin asphalt, polyethylene terephthalate (PET)-modified, and PET additive (PETA)-modified asphalt were established. At the molecular scale, the adsorption energy was used to predict the bond strength of the three interfaces, the radial distribution function was used to explore the interaction mode and stability of the interface and the static structure characteristics of the interface were analyzed in combination with the relative concentration. Finally, the interface’s dynamic behaviour was analyzed through mean square displacement and diffusion coefficient. The simulation results show that after adding PET and PETA, the adhesion energy between the asphalt and C-S-H gel increases by 0.72% and 17%, respectively. Modified asphalt has a smaller interfacial interaction zone and faster molecular diffusion than virgin asphalt. In addition, the interface system containing PETA exhibits stronger hydrogen bonding and significant homopolar aggregation behaviour. Overall, the adsorption effect of PETA-modified asphalt on cement-based materials was better than that of PET-modified asphalt and raw asphalt.

Analisis Karakteristik Material Lokal Kinang Jingkion dari Quarry Apalapsili, Habie Dan Hulikma, Serta Komposisi Campuran Terbaik Untuk Digunakan sebagai Bahan Lapis Pondasi Agregat Kelas A

The main road pavement works carried out in Yalimo Regency are flexible pavements using asphalt as the main adhesive. Asphalt produced outside Papua Island is transported to Jayapura using sea transportation, then transported to Wamena using air transportation, then transported to Yalimo Regency using land transportation, of course the price is not cheap when it arrives in Yalimo Regency. In addition to the price factor of asphalt material due to the relatively high transportation services, another thing that becomes a consideration for the need to use Kinang Jingkion material is the ease factor in working on roads using Kinang Jingkion which allows the local community to work on it using standard equipment that does not really require treatment or specific technology. According to these problems, further research on Kinang Jingkion material is urgently needed. Analysis of the Characteristics of the Local Material of Kinang Jingkion from the Apalapsili, Habie and Hulikma Quarry, and the Best Mix Composition to be Used as a Class A Aggregate Base Layer presents the results of the analysis related to the characteristics of the local Kinang Jingkion material taken from 3 different quarries namely Apalapsili, Habie and Hulikma, as well as results of testing the composition of the mixture to be used as a Class A Aggregate Base Layer.

Rheological properties and phase behaviour degradation of asphalt mastics under cyclic temperature variations

ABSTRACT Asphalt pavements are continuously subjected to cyclic temperature variations induced by varying day–night and seasonal temperatures. However, the effect of thermal cycling on asphalt materials has not been thoroughly documented. This study conducted accelerated thermal cycling tests on asphalt mastics to simulate the environmental temperature variation. The evolution of the rheological properties and phase behaviors under cyclic temperature variations was clarified. The temperature factors sensitive to damage were identified by establishing the quantitative relationship between the cyclic temperature parameters and these properties. Results demonstrated that, as the expansion of cyclic temperature ranges, the three asphalt mastics gradually lost their viscosity properties and became increasingly elastic. Thermal cycling increased the stiffness and high temperature deformation resistance of the three asphalt mastics, but significantly reduced their stress relaxation capability. The phase structures were degraded upon thermal cycling, weakening the asphalt-aggregate interaction. The temperature difference and cyclic high temperature were the primary factors affecting the rheological performance of the asphalt mastics. SBS modified asphalt mastic displayed remarkable resistance to thermal cycling, demonstrating its potential for application in regions with frequent temperature fluctuations. This research can help us understand the evolution of asphalt pavement performance in areas with frequent temperature changes at a macro-level.

A new approach to maximising the benefits of current intelligent compaction technology for asphalt materials

This paper investigates the correlations between asphalt density, intelligent compaction measurement values (ICMVs) and asphalt moduli obtained from different laboratory experiments at various temperatures of the asphalt mix AC14 with C320 bitumen. It was found that the influence of the density of asphalt on its modulus is primarily governed by the temperature of the asphalt mix. To examine the influence of asphalt temperature on ICMV-density correlations, a vibrating hammer instrumented with an accelerometer was employed to compact cylindrical asphalt specimens at different temperatures. The correlations between ICMVs and asphalt density at different temperatures showed that ICMVs are insensitive to the change in asphalt density at typical compaction temperatures. A practical method to maximise the benefits of the current intelligent compaction (IC) technology for quality control (QC)/quality assurance (QA) of asphalt pavements is proposed in this study. The proposed approach involves overlaying the ICMV map produced during the pre-mapping of the existing layer and the surface temperature map produced during the final roller pass of the newly-laid asphalt layer compaction to identify the most vulnerable regions for random spot density tests. The effectiveness of this approach was demonstrated for an asphalt overlay testbed compacted using an instrumented vibratory roller.

Asphaltene agglomeration through physical-chemical and rheological testing

A better understanding of the changes in binder chemistry and microstructure triggered by aging is fundamental as it increases the cracking susceptibility of asphalt materials and reduces pavement durability. In this context, this paper presents the findings of a collaborative study that delves further into the alterations in binder chemistry, microstructure, and rheology of laboratory – and field-aged binders using innovative experimental and fundamental theory techniques. An increase in polarity leading to a shift in the apparent molecular weight distribution (AMWD) towards higher molecular weights, which implies molecular agglomerations, could be observed as a result of aging via Saturates, Aromatics, Resins, and Asphaltene Determinator (SAR-AD) and Size Exclusion Chromatography (SEC), respectively. As for the theoretical methods, the δ-method and Molecular Agglomeration Index (MAI) that estimate the AMWD and incidence of molecular agglomeration, respectively, show satisfactory relationship with the SAR-AD and SEC results. This reinforces the soundness of the δ-method and MAI.

Economic and environmental assessment of a green pavement recycling solution using foamed asphalt binder based on LCA and LCCA

Cold-in-place recycling with foamed asphalt binders (CIR-F) has been considered as an environmentally sustainable option for asphalt pavement maintenance due to the low mixing temperature and the reuse of up to 100% of existing asphalt materials. However, the quantitative assessment of its economic and environmental performance from a life cycle perspective has rarely been addressed in the literature. To fill in the gap, this study conducted cradle-to-laid life cycle assessment (LCA) and life cycle cost analysis (LCCA) to estimate the annual energy consumption, carbon emissions, and equivalent uniform annual cost (EUAC) of CIR-F and compared it with the traditional mill & fill (M&F). The considered life cycle stages include raw material production, construction, transportation, and work zone traffic management. The heat map visualization technique was employed to explore the influence of service life on the relative environmental and economic advantages of CIR-F. The results show that both economic and environmental impacts of CIR-F were significantly reduced compared to conventional M&F, with 66.45% less cost, 59.62% less energy consumption and 45.73% less carbon emissions. Reducing the service life of CIR-F will reduce, or even completely offset, its benefits over M&F. Assuming a service life of 15 years for conventional M&F, the service life of CIR-F needs to be greater than 8 years to maintain its environmental advantage. The results of this study provide a quantitative assessment of the economic and environmental benefits of CIR-F, providing evidence for its broader application.

Effect of Additive Addition on RAP (Reclaimed Asphalt Pavement) as an Aggregate Substitution Against the Upper Surface Layer of The Road

As development in the field of infrastructure increases, it will require more materials of natural origin. The availability of materials from nature will be reduced and more limited. Meanwhile, the construction of infrastructure continues to run every year for the improvement and comfort of the community. With this, the importation of goods will also increase, especially for bulk asphalt materials, and it is possible that later the stone that becomes one of the main materials for hot asphalt mixture will also bring in from abroad. If waste from peeled asphalt (RAP) can be reused, it will automatically reduce the use of materials from nature and reduce import activities of goods which results in reduced state expenditure. The thesis task will discuss the reuse of peeled asphalt (milling) on the highway, starting from the benefits of RAP, the advantages of RAP, testing RAP materials and new materials, and how to produce RAP asphalt at the Asphalt Mixing Plant. The composition of the RAP used is 60% with SW1 rejunevile material of 3.8%, the addition of new aggregates of 40%, and the addition of new asphalt of 3.3%. The results of the compaction experiment in the field (trial compaction) which will be used for work reference are initial compaction (tandem roller 2 passing), intermediate compaction (tire roller 16 passing), and final compaction (tandem roller 1 passing), and the resulting density of hot mix beds of 98.36%.

Comparison of GPR (Ground Penetrating Radar) Penetration Results Using the GCB-400 Antenna on Flexible and Rigid Pavement

GPR (Ground Penetrating Radar) has been known as a tool used in non-destructive testing or in other words GPR can find out the conditions below the surface without damaging the layer above it. The GPR method is generally applied to roads namely flexible pavements and rigid pavements. This method has non-destructive properties because it utilizes electromagnetic waves in its operation, such as detecting the presence of objects or constituent layers at a certain depth. The penetration depth that can be achieved by GPR is influenced by three physical parameters, namely conductivity, relative dielectric permittivity (RDP), and magnetic permeability. In this study, GPR used the GCB-400 antenna model produced by the Swedish company Geoscanners. The research was conducted on roads with 2 different types of materials, namely asphalt (flexible pavement) and concrete (rigid pavement). Asphalt and concrete have different relative dielectric permittivity (RDP), where asphalt has an RDP of 5 and concrete has an RDP of 5.5. The results showed that there were significant differences between roads with asphalt and roads with concrete materials. On roads with asphalt material, GPR can reach a depth of more than 3 meters. On roads with concrete materials, GPR can only reach a depth of less than 2 meters.

Review of the utilization of plastic waste in asphalt pavements in hot climate conditions – KSA as a case study

In recent years, many global efforts have been made to advocate for the incorporation of recyclable waste materials into construction projects that utilize versatile asphalt. Hence, this review presents the use of modified asphalt with recyclable plastic materials in road construction as it relates to stability under extreme high temperatures. As per previous analysis, the addition of plastic does increase permanent resistance along with the increased work capacity of the asphalt. Although the effect of temperature on the asphalt shows no clear-cut results, the work capacity preferably increases at low temperatures. Current results have shown that the addition of polyethylene terephthalate (PET) does not provide strength to the asphalt because of its high melting nature; however, the addition of polypropylene (PP) provides substantial strength to asphalt when used in the construction of roads. Moreover, the addition of polyethylene (PE) and polyvinyl chloride (PVC) does not provide much more strength when implemented on a large scale. This report presents bonding interactions between asphalt and plastic waste that demonstrate that chemical molecular modeling can be used to predict recyclable modified asphalt stability. Hence, FTIR data supports that adhesive interactions exist between the asphalt and plastic polymer materials. Modified asphalt mixtures demonstrated high levels of improvement with the addition of ethylene–vinyl acetate (EVA) and styrene–butadienestyrene (SBS), as these structures provide strength characterized by C–H and C-O bond stretching generated with Fourier Transform Infrared analysis (FTIR). Furthermore, identifying the microstructural changes of asphalt modified with plastics and following the physical dispersions are made easier with the use of SEM imaging analysis.

Effects of using waste high-density polyethylene on the rheological, mechanical, and thermal performance of asphalt materials

Effects of using waste high-density polyethylene on the rheological, mechanical, and thermal performance of asphalt materials

Mitigation Strategy Selection for Asphalt Mixtures with High Reclaimed Asphalt Pavement Content

Economics and sustainability goals have driven higher use of recycled asphalt materials (RAMs), such as reclaimed asphalt pavement (RAP) and recycled asphalt shingles, in the pavement industry. Owing to the brittle nature of aged binders found in RAMs, a mitigation strategy is usually needed to ensure adequate cracking performance. Determining a proper mitigation strategy is vital to designing long-lasting asphalt concrete (AC) pavements with balanced performance. This study explored the use of mitigation strategies on AC mixtures with intermediate and high RAP contents, using materials from four mixtures that were part of a mill and overlay project in Milford, Delaware. This project included one standard mixture and three experimental mixtures with 25%–40% RAP. This paper presents performance data for field cores, plant-mixed laboratory-compacted specimens, and laboratory-mixed laboratory-compacted specimens. The effects and benefits of using a softer binder versus a recycling agent and the effects of using both a softer binder and a recycling agent to mitigate the stiff RAP binder are explored. To understand the effects of each mitigation strategy with aging, data from one-year field-aged cores and from laboratory-aged specimens are shown. Adjusting only one variable to mitigate the increased stiffness and brittleness of recycled binders yielded the best results in this study. Additionally, some test parameters were found to be sensitive to aging, including the flexibility index from the semicircular bend test and the cracking test (CT) index from the IDEAL-CT, while others were not observed to be sensitive to aging, including the fracture energy measured by the low-temperature disk-shaped compact tension test.

Environmental life cycle assessment of bridge deck pavement and case studies of two bridges in China

The durability of deck pavement material has great impact on deck performance and carbon emission. This paper aims to analyze the durability of different deck pavement materials and structures by taking two bridges across the Yangtze River in China as examples, and establish the carbon emission model of the bridge deck pavement during the whole life cycle. The carbon emissions of the two bridges during twenty years of service are then calculated based on the model. It can provide reference for future bridge deck pavement schemes and measures to reduce carbon emissions. In this paper, two typical representative bridges in Jiangsu Province in East China are selected for case analysis, namely the Jiangyin Yangtze River Highway Bridge and the Second Nanjing Yangtze River Bridge. Firstly, this paper introduces the specific forms of various bridge deck pavement schemes since the construction of the two bridges. After many years of experiments, the pavement of the Jiangyin Yangtze River Highway Bridge has changed from mastic asphalt mixture to double-layer hot mix epoxy asphalt concrete, and that of the Second Nanjing Yangtze River Bridge has changed from warm mix epoxy asphalt to hot mix epoxy asphalt. Focusing on the carbon emission of bridge deck pavement, the carbon emission model of different asphalt mixture pavements based on life cycle assessment (LCA) is established. The assessment can be divided into five stages: material production, transportation, construction, maintenance and demolishment. This paper takes extra traffic congestion during repair and maintenance into consideration. In this paper, two bridges were taken as cases to calculate the carbon emission. In initial construction, the deck of the Jiangyin Yangtze River Highway Bridge was paved with mastic asphalt mixture; while the deck of the Second Nanjing Yangtze River Bridge was paved with epoxy asphalt concrete. The paving material of the Jiangyin Yangtze River Highway Bridge was changed into epoxy asphalt concrete gradually in repair and maintenance. The analysis results show that in the initial 20 years of life, considering the initial construction and major maintenance of deck pavement, the total carbon emission of the Jiangyin Yangtze River Highway Bridge and the Second Nanjing Yangtze River Bridge is 179,195 kg CO2e and 101,577 kg CO2e respectively. The unit carbon emission of the Jiangyin Yangtze River Highway Bridge after 20 years of opening to traffic is 5.079 kg/m2 CO2e. The proportions of the five stages were 76.4 %, 2.7 %, 2.5 %, 16.8 % and 1.6 %, respectively. The unit carbon emission of the Second Nanjing Yangtze River Bridge after 20 years of opening to traffic is 3.352 kg/m2 CO2e. The proportions of the five stages were 66.3 %, 2.4 %, 2.6 %, 28.2 % and 0.6 %, respectively. The results show that epoxy asphalt material has better durability and can reduce carbon emission of bridge deck pavement.