Asphalt Damage Research Articles

IRodd (intelligent-road damage detection) for real-time infrastructure preservation in detection, classification, calculation, and visualization

Preserving roads involves regularly evaluating government policy through advanced assessments using vehicles with specialized capabilities and high-resolution scanning technology. However, the cost is often not affordable due to a limited budget. Road surface surveys are highly expected to use low-cost tools and methods capable of being carried out comprehensively. This research aims to create a road damage detection application system by identifying and qualifying precisely the type of damage that occurs using a single CNN to detect objects in real time. Especially for the type of pothole, further analysis is to measure the volume or dimensions of the hole with a LiDAR smartphone. The study area is 38 province’s representative area in Indonesia. This research resulted in the iRodd (intelligent-road damage detection) for detection and classification per type of road damage in real-time object detection. Especially for the type of pothole damage, further analysis is carried out to obtain a damage volume calculation model and 3D visualization. The resulting iRodd model contributes in terms of completion (analyzing the parameters needed to be related to the road damage detection process), accuracy (precision), reliability (the level of reliability has high precision and is still within the limits of cost-effective), correct prediction (four-fifths of all positive objects that should be identified), efficient (object detection models strike a good balance between being able to recognize objects with high precision and being able to capture most objects that would otherwise be detected-high sensitivity), meanwhile, in the calculation of pothole volume, where the precision level is established according to the volume error value, comparing the derived data to the reference data with an average error of 5.35% with an RMSE value of 6.47 mm. The advanced iRodd model with LiDAR smartphone devices can present visualization and precision in efficiently calculating the volume of asphalt damage (potholes).

Fracture evolution characteristics of asphalt concrete using digital image correlation and acoustic emission techniques

The cracking damage of asphalt concrete significantly affects the service life of pavement. The objective of this research is to investigate fracture mechanisms of asphalt concrete by employing a synergistic approach combining digital image correlation (DIC) and acoustic emission (AE) techniques under three-point bending tests. Firstly, the crack tip opening displacement (CTOD) and the fracture process zone (FPZ) derived from DIC were utilized to classify fracture stages and describe the entire crack propagation process. Meanwhile, AE-related parameters were applied to detect the internal damage and fracture characteristics. Subsequently, the results from DIC and AE were utilized for comparative analysis to evaluate the cracking resistance of different materials. Finally, the fractal dimension and AE b-value were used to distinguish the characteristics of the critical damage conditions. The results indicated that both techniques are effective in classifying the fracture stage of asphalt concrete. DIC can visualize and analyze crack propagation processes and paths on concrete surfaces, especially at the stage of macrocrack initiation and propagation. AE allows for continuous monitoring and highly sensitive detection of early-stage damage inside concrete. The distinct advantages of DIC and AE result in different fracture stage identification results at the early stage, but consistent after the appearance of macrocracks. Based on the relationship between CTOD and AE cumulative count, a simple approach is proposed to directly evaluate the cracking resistance of different asphalt concretes. The formation of macrocracks in asphalt concrete can be reflected by a shift where the correlation dimension drops steeply to the minimum value, and a minimum inflection point in the AE b-value curve acts as a precursor of complete fracture. The research offers an in-depth insight of both surface deformation and internal damage, thus enhancing the understanding of crack growth behavior and fracture process in asphalt concrete.

Pemanfaatan Penambahan Limbah Inner-Tube Rubber dan Penggunaan Abu Cangkang Kemiri Sebagai Substitusi Filler pada Campuran AC-WC

Various problems that occur in asphalt damage in Indonesia have triggered new innovations to deal with existing problems, one of which is by improving the quality of asphalt by adding substances (additives) or substitutions to the aggregate composition. This study aims to determine the utilization of inner tube rubber waste and the use of candlenut shell ash as a substitute filler in the AC-WC mixture. This study is an experimental study. The manufacture of test objects using an AC-WC mixture with a total of 18 test objects was then tested using the Marshall method. The results of this study indicate that the use of inner-tube rubber waste and candlenut shell ash greatly affects the Marshall parameter value. With an Optimum Asphalt Content of 6%, the best variation content was obtained at 3% of inner tire rubber additives and 25% substitution of candlenut shell ash as filler with a density value of 2.341 gr/cm3, VMA 15.50%, VIM 4.36%, VFA 71.87%, stability 1730.79 kg, flow 3.36 mm and MQ 565.01 kg/mm ​​which meets the 2018 Bina Marga Specifications Revision 2.

Investigation on the evolution of asphalt molecular structure under the salt erosion environment based on molecular dynamics simulation

Up to now, the underlying mechanism about the salt erosion aging of the asphalt has not been fully revealed yet, leading to the limitation of research on extending the lifespan of asphalt in salt erosion environment. Therefore, this work adopted the molecular dynamics (MD) method, aimed to investigate the potential mechanism of the salt erosion aging behavior of the asphalt from a molecular perspective. The asphalt models invaded by sodium sulfate and sodium chloride were established, and the invading salt amount was controlled to simulate the different aging degree. Various thermodynamics and energy parameters are output as simulation results. Results indicated that the potential energy and CED of the asphalt raise with the increasing amount of the salt invading into the asphalt, and the sodium sulfate exhibits a significant impact on increasing energy compared to the sodium chloride. Besides, the introduction of the salt increased the FFV of the asphalt, increasing the possibility of water damage in asphalt. Results of RDF exhibited that salt will intensify the self-assembly of the asphaltenes, which will endow asphalt with stronger elastic response. Moreover, at the same weight, sodium chloride had a larger number of ions, which formed wider connection with the asphaltenes, leading to a more serious self-assembly behavior compared to the sodium sulfate. In addition, the curve of relative concentration showed that the presence of salt prompted the weak or no polar fractions to separate from asphalt and enter the aqueous phase, which was called salt-out. Finally, an aging test in the laboratory was conducted, and the results prove the accuracy of the simulation.

Study on the influence of tire polishing on surface texture durability and skid resistance deterioration of asphalt pavement

As an inherent attribute of asphalt pavement, texture durability is the essential reason for the change in skid resistance. However, different scale texture deterioration behavior remains unclear by tire wearing at present. To explore the influence of the durability of multi-scaled textures on skid resistance, nine pavement specimens were tested using the Harbin polishing and dynamic friction integrated experimental machine (HPFM). The pavement anti-skid texture tester (PATT-II) was used for high-precision texture scanning and reconstruction. The results show that the texture richness and skid resistance of the three types of pavements in 300 min polishing are ranked as Open-graded Friction Coarse (OGFC) > Stone Mastic Asphalt (SMA) > Asphalt Concrete (AC), while SMA presents the best durability, determined by the material skeleton structure of asphalt mixture. The macro-texture deterioration occurs slightly at first and then tends to stabilize in 300 min polishing. The micro-texture deterioration behavior is the same as the μHPFM, increasing rapidly at the beginning, then slowly decreasing, and finally remaining constant. This deterioration is caused by the asphalt damage and continuously wearing aggregate surface. The 2D-PSD deterioration behavior is more significant with a smaller texture scale in 300min polishing, and the most considerable contribution wavelength in the microscopic scale range is 0.15 mm–0.3 mm, which is determined by the adhesion characteristics and molecular mechanism between a mineral mixture and asphalt material. The influence of pavement texture on the dynamic friction coefficient is significantly different under different water film thicknesses, the micro-texture and macro-texture play the main roles in boundary and mixed lubrication, respectively.

Susceptibility to moisture damage in asphalt mixes with blast furnace dust as aggregate

One of the ongoing challenges in engineering is mitigating the degradation of road infrastructure caused by water in asphalt mixes. This study aims to assess the impact of blast furnace dust, a byproduct of the steel manufacturing process, on moisture-induced damage in asphalt mixes. Three asphalt mixes were developed following the Marshall methodology: one comprising conventional crushed aggregates, while the others substituted 50% and 100% of the conventional fine aggregate with blast furnace dust. Material characterization procedures and chemical analysis of the blast furnace dust were conducted. Once compliance with the specified material requirements was verified and analyzed, water susceptibility was evaluated through an indirect tensile test across various void content levels. Similarly, leveraging the Superpave gyratory compactor, several compaction indices were determined to estimate the compaction behavior of each mix. Based on the findings, the inclusion of blast furnace dust in an asphalt mix proved satisfactory due to its contributions in enhancing tensile strength, consequently leading to a reduction in moisture-induced damage within the asphalt mix, as well as exhibiting improved compaction behavior. Additionally, this utilization contributed to diminishing the environmental impact linked to the steel production process, where substantial quantities of this residue accumulate.

Experimental investigation and evaluation of the compactness and moisture damage of asphalt mixes incorporating dune and river sand

Road construction is mainly based on the use of raw materials that must be in compliance with the standards, thus ensuring the quality and durability of the road. The use of dune sand and river sand in road geotechnics is an interesting subject. Both types of sand can be used in road construction and maintenance for a variety of applications. Dune sand is often appreciated for its uniform grain size and drainage capacity, while river sand can offer good mechanical strength. The majority of common bituminous mixes contain fillers made of quarry sand, whose amounts are difficult to regulate because of the variety of rock deposits and the conditions under which they are manufactured. In this paper, the compactness and moisture damage of asphalt mixes with two sand types, River sand (RS) with (0/4) size was sourced from the valley in the province of Medea (Algeria) and Dune Sand (DS) with a particle size of (0/0.5) was obtained from a dune in the Algerian province of Djelfa, were examined. Furthermore, a 100% replacement rate by weight of Crushed Sand (CS) with (0/3) mm size was used (quarry sand). The investigation employed a comprehensive approach, utilizing Marshall and gyratory shear compaction tests to assess compactness, while moisture damage was evaluated through rigorous water resistance testing and compressive strength methodology. The results of the study reveal a notable disparity in the mechanical performance of asphalt mixtures containing dune and river sand, showcasing diminished compactness and heightened susceptibility to moisture-induced damage when compared to alternative mix formulations. These findings underscore the critical role of sand type selection in asphalt mix design, emphasizing the need for careful consideration to optimize performance and durability.

Effect of incorporation of calcined sediments and perlite as partial cement replacement on mortars behavior

The accumulation of sediments in varied dams built in Algeria denotes a vital problem that requires immediate attention and action from the authorities and managers of the National Agency for Dams and Transfers (ANBT). More than that, various research studies on sediments have revealed that subjecting them to heat treatment can exploit these sediments as a viable substitute for some of the cement used to produce cementitious materials. Combining the different types and quantities of natural Perlite pozzolan can achieve many benefits, including reduced consumption, minimized heat generation, improved workability, reduced permeability, and increased strength. This study aims to explore the potential of using dredged sediments from Chorfa II dams and perlite from Hammam Boughrara (located in western Algeria) as substitutes for cement in mortar analysis. A thorough examination of calcined sediments and perlite revealed the feasibility of partial cement replacement. Research has mainly focused on evaluating the properties of mortars in fresh and hardened states.

Evolution of Rheological and Microscopic Properties of Asphalt Binders under Fuel Corrosion

Vehicle fuel leaks can adversely affect the performance of asphalt pavements. To study the mechanisms of fuel corrosion damage in asphalt, four asphalt binders were selected in this study, and the evolution of their rheological and microscopic properties was investigated. Fuel corrosion caused continuous mass loss in asphalt binders. Base asphalt lost more than 50% of its mass after 24 h of fuel corrosion, while modified asphalts had better resistance. According to dynamic shear rheometer tests and multiple stress creep recovery tests, modifiers improved the high-temperature rheological properties of these asphalt binders. As the degree of fuel corrosion deepened, the indexes characterizing the high-temperature performance deteriorated. Rubber-modified asphalt showed the best resistance to high-temperature deformation, while the performance of LDPE-modified asphalt was more stable. In contrast, fuel corrosion improved the resistance of asphalt binders to low-temperature cracking to some extent: the creep strength (S) decreased as the creep rate (m) increased, and the resistance of SBS-modified asphalt to low-temperature cracking was optimal, with a 36% decrease in S-value after 24 h of fuel corrosion. Fourier transform infrared spectroscopy tests showed that diesel corrosion was a process of this physical dissolution, with no change in the chemical functional groups. Meanwhile, by using fluorescence images and analyzing the four-component test results, we found that fuel corrosion disrupted the stabilized structure formed by the modifiers, and the heavy components in the asphalt binders were converted into light components. This study reveals the evolution of the rheological and microscopic properties of asphalt under fuel corrosion, which can provide a reference for the optimization of fuel corrosion resistance in asphalt pavement.

Study on asphalt damage characteristics in cold area with large temperature gradient

The primary cause of the asphalt pavement disease in this region is the large temperature differential and high ultraviolet (UV) radiation that characterize this frigid environment. This study assessed the ductility, penetration, softening point, and rheological properties of several asphalts under various freeze-thaw cycles and UV aging conditions. Additionally, the damage characteristics of asphalt in cold and large temperature gradient areas were examined. The findings indicate that the freeze-thaw cycle significantly affects the asphalt’s low-temperature crack resistance but has no discernible effect on the material’s traditional performance or high-temperature rutting resistance. Asphalt’s resistance to low temperature cracking is ranked according to the impacts of UV radiation and the freeze-thaw cycle: 80/100 pen grade asphalt, 100/120 pen grade asphalt, SBS modified asphalt, and SBR modified asphalt. The impact of UV radiation and the freeze-thaw cycle on the high temperature performance of asphalt is categorized into four categories: SBR modified asphalt, SBS modified asphalt, 80/100 pen grade asphalt, and 100/120 pen grade asphalt.

The investigation of surface free energy components and moisture sensitivity damage of asphalt mixes modified with carbon black using the sessile drop method

Asphalt pavement is vulnerable to moisture damage when water infiltrates the asphalt-aggregate interface and weakens their bond. To prevent this problem, researchers have explored the use of additives to increase resistance against moisture damage. The moisture sensitivity of asphalt mixtures can be assessed by measuring their basic properties related to the mechanism of moisture damage. One effective approach to this is using the surface free energy method, which calculates bond energies between different materials’ surfaces and identifies the most appropriate combination of asphalt and aggregate. High cohesion or adhesion bonding is crucial for the proper performance of asphalt mixtures, such as moisture damage resistance. This study aimed to investigate the effect of carbon black additive on moisture damage resistance using surface free energy methods, comparing results with the Tensile Strength Ratio (TSR) test. Modified asphalts containing 4, 8, 12, and 16% carbon black were tested, with natural base asphalt as a control sample. The study used surface free energy theory to determine moisture sensitivity parameters of asphalt mixtures by obtaining surface free energy components of the raw materials and testing the ratio of tensile strength. Results showed that adding 8% carbon black to the asphalt mixture improved moisture sensitivity, and increasing additive content up to 16% reduced it but still provided better results than samples made with pure asphalt. The study concluded that the surface free energy method can determine the suitable combination of asphalt and aggregate materials for resistance against moisture damage.

Digital image colour analysis to evaluate the moisture sensitivity of hot-mix asphalt mixes

Moisture in hot-mix asphalt (HMA) can cause serious damage such as cracks and ruts if left untreated. This is due to the separation of binder and aggregates caused by moisture-induced stripping. Existing approaches for assessing moisture damage in asphalt are time consuming, destructive and expensive to implement. In contrast, digital image analysis provides a simple, inexpensive and non-destructive method for identifying moisture-sensitive mixes. Colour, as an essential characteristic of an image, effectively conveys information about its content. This study seeks to explore the potential of analysing digital image colour in the L*a*b* colour space to assess the moisture sensitivity of HMA after moisture-induced stress tester conditioning. Laboratory-compacted specimens of loose asphalt mixtures from the field were studied by image processing followed by statistical tests of significance. It is found that two parameters – namely, the ‘average colour value for the L* channel’ and the ‘standard deviation value for the b* channel’ – can be used to distinguish between moisture-sensitive and non-sensitive mixes. The findings of this study suggest that future research may find colour to be a helpful criterion for characterising asphalt materials using digital image processing.

Deep learning techniques for multi-class classification of asphalt damage based on hamburg-wheel tracking test results

In recent years, advancements in deep learning (DL) have been leveraged in civil engineering, but further exploration is necessary to apply DL techniques to asphalt research. These advances involve employing computer vision tasks and machine learning approaches to solve current challenges and develop innovative solutions for the conservation and monitoring of roads. In the laboratory, the Hamburg-Wheel Tracking (HWT) test simulates expected vehicle traffic and evaluates permanent deformation, such as rutting in asphalt mixtures. Current works focus on detecting the damages in the asphalt but do not classify the level of damage, which is the novelty proposed in the present work for rutting evaluation. This study aims to classify images of asphalt damage based on surface deformation caused by the HWT test. The dataset built and implemented in this study -called by the authors HWTBench2023- consists of 1198 images of asphalt samples subjected to controlled HWT conditions with varying levels of damage. The study employs a multi-class classification model based on convolutional neural networks (CNNs). The CNN was calibrated with transfer learning and fine-tuning hyperparameters. The outcomes demonstrate a high degree of accuracy, where the validation test showed an overall accuracy of 89 %, with F1-score values over 89 %. The model developed in this research identifies the presence or absence of damage and quantifies the damage level. In addition, the model was evaluated on a different dataset containing asphalt pavement photographs with rut damages. The model’s performance detecting rut damage on asphalt pavement under actual conditions indicates its adaptability to new images not included in the model’s learning stage. Therefore, this study improves methods for fast assessing rutting deterioration in asphalt pavements with transfer learning, provides accurate measurements of pavement deformation, and helps identify maintenance and rehabilitation needs.

PERENCANAAN PERKUATAN PERLINTASAN KERETA API SEBIDANG DENGAN MENGGUNAKAN PLAT BETON BERTULANG

lroad track and a motorized highway. Based on data and field reports at railroad crossings with highways, it is often found that damage to the asphalt layer (Surface Coarse). The cause of asphalt damage occurs due to a shift between the ballast gravel under the asphalt surface. Where the asphalt layer should be on a solid pavement or foundation, so that the life of the asphalt surface will be more durable. So to overcome these problems, a comparative study was conducted on the planning of retrofitting of the crossing using reinforced concrete slabs and using used railroad tracks. In the design of the reinforced concrete slab, a plate measuring 3x0.6 meters thick 7 cm with a concrete quality of K-225 (18.68 Mpa) is used which can withstand a train axle load of 18 tons. The load on the used railroad tracks is used by large-loaded vehicles, namely truck loads of 10 tons

Future Directions for Applications of Bio-Oils in the Asphalt Industry: A Step to Sequester Carbon in Roadway Infrastructure

The global emphasis on sustainability and net zero carbon roads combined with the increased cost of crude oil has necessitated the application of new environmentally friendly alternatives to the bitumen used in asphalt by the pavement industry. Physical aging, chemical aging, and moisture damage are three important matters encountered in the pavement industry that are harmful for asphalt; bio-oils can decelerate the rates of physical aging and chemical aging in virgin bitumen, and bio-oils can substantially improve virgin bitumen’s resistance to moisture damage. Bio-oils can also restore properties in environmentally damaged asphalt up to a certain limit of aging. The main goal of this review is a comprehensive analysis of the literature about the potential of bio-oils produced from different biomass sources to influence the physical aging, chemical aging, and moisture damage of asphalt. Considering that bitumen’s physical aging is highly impacted by the bitumen’s wax content, this review also covers the effect of wax inherently present in bitumen or wax added to bitumen as a modifier. It is concluded that the chemical composition of a bio-oil has a significant impact on the bio-oil’s ability to protect or recover the bitumen’s original properties. Phenolic compounds found in bio-oils have antiaging effects while bio-oils’ acidic compounds may lead to moisture susceptibility.According to the literature, most bio-oils have positive effects only in a specific range of temperatures: low, intermediate, or high. Complete miscibility and dispersion of a bio-oil in the asphalt matrix also have a significant influence on making a bio-oil an effective modifier. Generally, bio-oils are promising as sustainable, carbon-neutral, cost-effective alternatives to replace or modify conventional bitumen in the pavement industry. This review has identified the following critical research gaps: (1) the lack of standard methods for evaluating and reporting the performance characteristics of each bio-oil in bitumen; (2) the lack of long-term field performance data on bio-oils to support comprehensive life-cycle assessments and life-cycle analyses; (3) high variation among bio-oils made from the same feedstock through different processing methods, leading to variation in performance characteristics; (4) the lack of accurate technoeconomic analysis on industrial bio-oils to facilitate entry of bio-oils into the asphalt market.

Aging effect of damp-heat and saline-alkali environment on fatigue performance and chemical evolution of asphalt

ABSTRACT Asphalt in damp-heat and saline-alkali areas is prone to damage, which resulting in fatigue failure of the mixture. However, the aging damage of asphalt in these areas has not been paid enough attention, and there is a lack of effective evaluation method for asphalt’s fatigue performance. In this paper, the base asphalt and SBS-modified asphalt were immersed in several solutions (water, NaCl and Na2CO3) to simulate aging conditions and the frequency sweep test was employed to determine the viscoelasticity properties of the asphalt. And the fatigue properties of the asphalt were analysed by the simplified viscoelastic continuum damage model. The microstructural and chemical evolution of asphalt was investigated by SEM, FTIR, the pH value and total organic carbon tests. After being immersed, the anti-deformation properties of two asphalts were strengthened. The solution erosion led to an increased loss rate of the integrity factor C*, and resulting in weakened fatigue properties of asphalt. The oxygen-containing functional group gradually increased with the extension of immersion. There were chemical interactions in addition to physical interface disruption during the immersion process. Moreover, the influence of Na2CO3 solution on asphalt ranked first due to the highest molar concentration of Na+ and the OH− produced by hydrolysis of C O 3 2 − .

Effect and mechanism of waste glass powder silane modification on water stability of asphalt mixture

The loss of adhesion is one of the primary mechanisms of water damage in asphalt mixes containing waste glass powders (WGPs), which is mainly attributed to the smooth surface of the glass may undermine the bitumen–aggregate adhesion and accelerate the stripping. In this study, the WGPs surface was roughened by different types and content of silane coupling agent (SCA), and the surface modification mechanism was illustrated based on the chemical reaction process. Then the adsorption capacity of WGPs on SCA was studied through UV–vis tests, and the effects of the SCA on the chemical composition of WGP and asphalt were investigated by FT-IR tests. At the same time, the adhesion performance between modified WGPs and asphalt was studied by the sessile drop test and column wicking test. Furthermore, the immersion Marshall tests were completed to study the water stability of the asphalt mixture after the replacement of filler with modified WGPs. Results show that the optimal modified time of WGPs is 75 min. During the modified process, a ≡Si-O-Si≡ skeleton structure is generated between the SCA and WGPs, and the amino group in SCA reacts with the carboxylic acid of the asphalt to form a new chemical bond. In addition, adding 10 % KH550 SCA to modify the WGPs will provide the most superior improvement for the adhesion work, stripping work and water stability.

Influence of Micro-Crack Healing on Viscoelastic Properties of Moisture Damaged Asphalt Concrete

One of major asphalt pavement distresses is the moisture damage which influences the degradation of the viscoelastic properties of the mixture. The present work assesses the impact of practicing micro-crack healing on the viscoelastic properties of moisture damaged asphalt concrete. Roller compacted slab samples of asphalt concrete were prepared at optimum binder content. Beam specimens were obtained from the slab samples and subjected to moisture damage. Part of the asphalt concrete beam specimens were then tested under dynamic flexural stresses, while another part of the asphalt concrete beams was subjected to micro-cracks healing process using external heating at 60° C for 120 minutes, then tested under the dynamic flexural stresses. The viscoelastic properties of asphalt concrete in terms of permanent deformation, flexural stiffness, phase angle, and cumulative dissipated energy were monitored and compared among both testing conditions. It was observed that a significant increase in the flexural stiffness could be observed after healing. The increase in the phase angle after healing is significant at the early stages of loading. Higher cumulative dissipated energy could be observed for mixture which had practiced micro-crack healing. It was concluded that healing process does not exhibit positive influence on permanent deformation of moisture damaged asphalt concrete. A significant increase of 41.6 % in the flexural stiffness could be observed after healing after the first load repetition as compared with the mixture before healing. The permanent deformation after healing is higher by 22 % at failure as compared with that of mixture before healing.

Measuring moisture damage of hot-mix asphalt (HMA) by digital imaging-assisted modified boiling test (ASTM D3625): Recent advancements and further investigation

Boiling water test (ASTM D3626) has been utilized to investigate the moisture susceptibility of asphalt mixture for decades. It was originally intended to compare the relative moisture resistance of a few mixtures, and the degree of stripping after the boiling was recorded based on visual observations. In recent years, several digital imaging-assisted modified boiling tests have been proposed, which significantly improved the accuracy of test results. This paper reviewed the recent advancements (2009–2022) in different test methods by digital imaging. The limitations and challenges of each method were also discussed and compared to each other. In addition, further experiments were performed to investigate the effect of aging, boiling time and water quality on the coating ratios. The boiling test results of sixty loose mixtures were compared to the tensile strength ratios (TSRs). Based on the results, the boiling water test with enhanced accuracy by image processing can be potentially developed as a measure of field performance. More importantly, the test should be conducted immediately after the mixing of asphalt and aggregate, and the aging of asphalt mixtures could significantly increase the results of coating ratios up to 100%, which made the boiling test unable to identify moisture susceptibility. It was found that the boiling water could not strip asphalt from aggregate after a long time of aging even though the moisture damage occurred and weakened the bond between asphalt and aggregate. In addition, the water quality could considerably influence the boiling test results, and the use of distilled water might underestimate the moisture damage of asphalt mixtures subjected to acid rain.

Moisture Damage of Asphalt Based on Adhesion, Microsurface Energy, and Nanosurface Roughness

Moisture Damage of Asphalt Based on Adhesion, Microsurface Energy, and Nanosurface Roughness