Pavement Mixtures Research Articles

Evaluation of healing characteristics of reclaimed asphalt pavement (RAP) mixtures using monotonic loading

Evaluation of healing characteristics of reclaimed asphalt pavement (RAP) mixtures using monotonic loading

The design of long afterglow pavement mixture by optimizing optical properties and basic road performance

This study designed two types of long-afterglow pavement mixtures with high transparency bright asphalt and polyurethane as cementing materials. The photoluminescence properties of long-afterglow luminescent gravel were designed to achieve self-luminescence effect for pavement use. The optimal amount of cementitious material was determined to be 6.2% by the Marshall method, and four kinds of pavement mixtures with luminous gravel content were designed, and the optical properties and basic road properties of each mixture were evaluated. In this study, the mix ratio design of long afterglow pavement mixture was studied from the perspective of optical properties and basic road performance, which provided a new reference and idea for the development of self-luminous pavement mixture. And the conclusion of the road optical properties and basic road performance suggests the possibility of the application of the long afterglow pavement mixtures.

The time history of dynamic response of permeable asphalt mixture pavement based on PFC2D

To investigate the dynamic response of permeable asphalt mixture pavements, a discrete element model was developed using PFC2D under the coupling of seepage and stress fields. This study examines the excess pore water pressure and dynamic behavior of permeable asphalt mixture pavements under the coupling of seepage and stress fields. The findings indicate that the excess pore water pressure amplifies compressive strain and stress at the base of the permeable asphalt mixture over time, while exhibiting alternating positive and negative fluctuations as a roller traverses the pavement.

Feasibility Assessment of Mudstone Aggregate as an Alternative Material for Colored Asphalt Pavement in South Korea

Colored asphalt pavements have been implemented in South Korea to enhance visibility and lane distinction; however, color fading, accelerated deterioration, and increased pothole occurrence have been noticed. As a solution, alternative materials that can be used for the construction of colored asphalt pavements are being explored. This study evaluates the feasibility of using mudstone aggregate in constructing colored asphalt pavement in South Korea. Initially, aggregate quality tests were conducted on mudstone samples to assess their suitability compared to standard criteria. To enhance the visibility and color retention of colored asphalt, addition of pigment in the colored asphalt pavement mixture was considered and evaluated. The asphalt mixtures were evaluated for deformation, crack and viscoelastic properties using the Kim test, indirect tensile (IDT) strength test, and dynamic modulus test, respectively. Results showed that mudstone aggregate exceeded quality standards and the colored asphalt mixtures demonstrated superior deformation strength and crack resistance compared to typical SMA. However, the addition of pigment slightly reduced these properties. Overall, the findings suggest mudstone aggregate as a viable alternative for constructing colored asphalt pavements, offering potential improvements in durability and color retention.

Recognition and Characterization of Nanoscale Phases: Modulus Mapping of Asphalt Film in Pavement Mixture Cores.

The objective of this study is to recognize and characterize the nanoscale phase modulus mapping of the asphalt film in pavement mixture cores using atomic force microscopy quantitative nanomechanical technology. The pavement core samples from the upper and middle layers of four highways and laboratory samples were taken as the research object. The phase modulus-macro property correlation of recovered asphalt was analyzed using mathematical statistics. The results showed that the pavement core samples had more significant multi-phase and diversified phase characteristics compared to lab samples. This indicated that the asphalt in the pavement core had an obvious phase separation phenomenon due to aging. The phase modulus of each sample was distributed across a relatively wide numerical range, and there were also many numerical points with large fluctuations. Especially for the mixture sample containing SBS (Styrene-Butadiene-Styrene)-modified asphalt, the phase modulus distribution mappings presented a multi-peak phenomenon. Hence, considering the distribution characteristics of the data, the box plot method was introduced. Compared with quantified results from laboratory samples, the phase modulus of SBS-modified asphalt increased by 0.96 times, 1.18 times and 1.15 times, and that of base asphalt increased by 0.59 times, 0.56 times, 0.42 times, 1.24 times and 0.39 times, respectively. This indicates that the aging degree of asphalt in the upper layer was generally greater than that of the asphalt in the middle layer and that there was an aging gradient in the direction of pavement depth. All points were within the 95% confidence band in terms of correlation fitting, indicating a better fitting effect between phase modulus and complex shear modulus, as well as between phase modulus and penetration. This research provides innovative ideas for future multi-scale numerical simulation and cross-scale performance model development of asphalt binders.

Field and Laboratory Performance Evaluation of Cement Treated Cold Recycled Asphalt Pavement Mixtures

Field and Laboratory Performance Evaluation of Cement Treated Cold Recycled Asphalt Pavement Mixtures

Understanding Toughening Mechanisms and Damage Behavior in Hybrid-Fiber-Modified Mixtures Using Digital Imaging

Pavement cracking is a primary cause of early damage in asphalt pavements, and fiber-reinforcement technology is an effective method for enhancing the anti-cracking performance of pavement mixtures. However, due to the multi-scale dispersed structure of pavement mixtures, it is challenging to address cracking and damage with a single fiber type or fibers of the same scale. To investigate the toughening mechanisms and damage behavior of hybrid-fiber-modified mixtures, we analyzed the fracture process and damage behavior of these mixtures using a combination of basalt fiber and calcium sulfate whisker hybrid fiber modification, along with semicircular bending tests. Additionally, digital imaging was employed to examine the fracture interface characteristics, revealing the toughening mechanisms at play. The results demonstrated that basalt fibers effectively broaden the toughness range of the modified mixture at the same temperature, reduce mixture stiffness, increase residual load at the same displacement, and improve crack resistance in the mixture matrix. While calcium sulfate whiskers enhanced the peak load of the mixture, their high stiffness modulus was found to be detrimental to the mixture’s crack toughness. The fracture interface analysis indicated that the three-dimensionally distributed fibers form a spatial network within the mixture, restricting the relative movement of cement and aggregate, delaying crack propagation, and significantly improving the overall crack resistance of the mixture.

Experimental Study of the Semicircular Bending Test for Estimating the Flexural Strength of Concrete Mixtures for Pavements

Experimental Study of the Semicircular Bending Test for Estimating the Flexural Strength of Concrete Mixtures for Pavements

Study on the Road Performance and Compaction Characteristics of Fiber-Reinforced High-RAP Plant-Mixed Hot Recycled Asphalt Mixtures.

Recycled asphalt pavement (RAP) mixtures are widely adopted due to their significant economic and social benefits from utilizing pavement recycling materials. This study incorporates basalt fibers (BF) and polyester fibers (PF) into plant-mixed hot recycled asphalt mixtures to analyze their enhancement effects on the high-temperature, low-temperature, and fatigue performance at different RAP content levels. Additionally, the study investigates the impact of fiber and RAP additions on the compaction characteristics of the mixtures using gyratory compaction tests, aiming to increase the RAP content of plant-mixed hot recycled asphalt mixtures. Experimental results demonstrate that at 30% and 50% RAP content levels, basalt fibers exhibit more pronounced enhancement effects on the performance of recycled asphalt mixtures compared to polyester fibers. Incorporating basalt fibers increases the fracture energy of recycled asphalt mixtures by 8.63% and 13.9%, and improves fatigue life by 154% and 135%, respectively. Moreover, the addition of both types of fibers increases compaction difficulty, with polyester fibers showing a more significant influence on the compaction energy index (CEI).

Modified Asphalt Using Buton Natural Rock Asphalt

he characteristics of asphalt mostly determine how well asphalt pavements work. High temperatures can cause stress on the asphalt surface layer. At high temperatures, irreversible alteration or bubbling occurs and leads to spalling as it travels. This is due to the slow movement of the asphalt components in the pavement mixture, which resists the strain caused by traffic. This is because the pavement mix's viscous asphalt matrix flow resists stresses brought on by vehicles. As a result, the rheological characteristics of asphalt, which may be altered, have a significant impact on pavement performance. In this study, Pen. 60/70 asphalt was modified by using Buton Natural Rock Asphalt (BNRA). A total of 10 to 25% of fine BNRA passing sieve #200 was added to the asphalt. Four mixtures of asphalt and BNRA were then tested for penetration and softening point. From the Penetration and Softening Point test results, thePenetration Index (PI) was determined. The PI results obtained were 0; 0.2; 0.1; 0.1; and 0.4 for BNRA content of 0, 10, 15, 20, and 25%. The higher the PI value of asphalt, the lower its temperature susceptibility. It can be seen that with the addition of BNRA, the asphalt is more resistant to temperature changes. While it is evident that BNRA affects the resistance of asphalt to temperature changes, it is also evident that its strength.

Study on the Application of Kramers-Kronig Relation for Polyurethane Mixture.

Polyurethane (PU) mixture, which is a new pavement mixture, exhibits different dynamic properties compared to a hot-mixed asphalt mixture (HMA). This paper analyzed whether the Kramers-Kronig (K-K) relation and thermorheologically simple properties applied to the PU mixture. Based on the results, the PU mixture exhibited thermorheologically simple properties within the test conditions. The time-temperature superposition principle (TTSP) was applicable for the PU mixture to construct a dynamic modulus master curve using the standard logistic sigmoidal (SLS) model, the generalized logistic sigmoidal (GLS) model, and the Havriliak-Negami (HN) model. The Hilbert integral transformed SLS and GLS models for the phase angle can accurately fit the measured phase angle data with newly fitted shift factors and predict the phase angle within the viscoelastic range. The core-core and black space diagrams both displayed single continuous smooth curves, which can be utilized to characterize the viscoelastic property of the PU mixture. The K-K relation is applicable for the PU mixture to obtain the phase angle master curve model, storage modulus, and loss modulus from the complex modulus test results with the test temperatures and loading frequencies. The phase angle of the PU mixture at extremely high or low test temperatures cannot be derived from the dynamic modulus data.

Evaluation of an Asphalt Mixture Containing a High Content of Reclaimed Asphalt Pavement (RAP) Materials with Epoxy Asphalt

The average content of reclaimed asphalt pavement (RAP) materials in asphalt mixtures for new pavements is around 22% in the current paving practices in the United States. Increasing this content has significant economic and environmental benefits. This study explored the approach of producing asphalt mixtures with 100% RAP materials by adding a small percentage of epoxy asphalt. Specimens of 100% RAP mixtures with low contents of epoxy asphalt were fabricated and evaluated in the laboratory for their properties related to pavement performance, including Marshall stability and flow, indirect tensile strength, resistance to moisture damage, resistance to fatigue damage, and fracture resistance. The results showed that the specimens made of 100% RAP materials selected in this study without a new binder or rejuvenator had low workability and high Marshall stability and indirect tensile strength but poor resistance to moisture damage and fatigue damage. A low percentage (0.5 to 2%) of epoxy asphalt significantly improved the resistance to moisture and fatigue damage of the 100% RAP mixture, and this improvement increased with the epoxy asphalt content. The fracture resistance of the 100% RAP mixture was also significantly improved by a low dosage of epoxy asphalt at a low temperature (8 °C), but the improvement was less significant at a moderate temperature of 25 °C.

Investigating the Field Performance of High- Recycled Asphalt Pavement Mixtures with Bio-oil Recycling Agent

The use of recycling agents (RAs), along with recycled asphalt pavement (RAP) modifiers, has been increasing over recent years. However, the field performance of asphalt mixtures containing high-RAP materials modified with RAs has raised some concerns with the long-term performance of RAs. This study evaluated the laboratory and field performance of high-RAP mixtures with and without bio-oil RA. Five sets of plant-produced specimens were collected: 1) plant-produced laboratory-compacted; 2) field-compacted, cored after paving; 3) field-compacted, cored after one year; 4) field-compacted, cored after two years; and 5) field-compacted, cored after three years. The Hamburg wheel tracking test was used to evaluate the specimens’ resistance to rutting and moisture damage, while the semi-circular bending test was performed to examine the cracking resistance of specimens. The laboratory test results showed that using the bio-oil RA increased cracking resistance and decreased rutting and moisture damage resistance of the RAP-blended mixtures. However, after one and two years of exposure to environmental conditions and traffic loads, the specimens modified by RA showed better moisture damage and rutting resistance. The cracking resistance of laboratory and field-aged specimens, estimated by flexibility index, implied that the bio-oil RA used in this study could not provide long-term improvement for the RAP-blended mixtures. Field observations suggest that using bio-oil RA may have resulted in inferior pavement performance compared with the control section. However, drawing conclusions based on just two years of data might yield inconclusive results. Longer field performance monitoring is, therefore, warranted for a more comprehensive analysis.

Development of Macrotexture Test Method for Dense-Graded Asphalt Mixtures

The design and construction of pavements necessitate careful consideration of longevity, cost-effectiveness, sustainability, and safety, with a focus on enhancing the durability and lifespan of dense-graded asphalt (DGA) surface mixtures. This paper discusses a research project the Federal Highway Administration (FHWA) initiated to assess the macrotexture characteristics of DGA mixture pavement—particularly concerning safety at higher speeds. The project aims to develop an efficient testing procedure for measuring macrotexture during mixture design and field-testing processes, striking a balance between longevity, cost-effectiveness, sustainability, and safety in pavement design and construction. The study began with a comprehensive review of existing practices, leading to the selection and testing of a unique laser texture scanner capable of noncontact macrotexture measurement. The subsequent phase involved validating the suggested macrotexture measurement system through data collected from State-sponsored projects under the FHWA Mobile Asphalt Technology Center program. Macrotexture measurements were collected from field cores and laboratory-compacted specimens from various State departments of transportation projects and analyzed. Preliminary analysis of the limited dataset to date revealed a positive correlation between average macrotexture measurements from gyratory specimens’ top surface and field core macrotexture measurements. The FHWA developed a draft test method for measuring macrotexture on laboratory specimens and field cores, thereby aiming to reduce procedural variability. Interlaboratory macrotexture test results demonstrated good reproducibility, with an average coefficient of variation of approximately 20%. Overall, this research project seeks to advance the understanding and measurement of macrotexture in DGA mixture pavements and thereby contribute to the development of safe pavements.

The Utilization of Coconut Shell Ash Waste as Filler in Pavement Mixture towards Green Infrastructure

Road is one of the most important land infrastructure in supporting community activities and regional development. The problem with current road construction is the increasingly limited availability of natural materials, so it necessary to innovate materials made from waste. This research utilizes waste material in the form of coconut shell ash as a filler towards the realization of green infrastructure. The purpose of this research was to obtain the characteristics of filler, aggregate, asphalt and their effect on road pavement mixtures. The research method is research in the laboratory. The results obtained are that the physical properties of aggregate, asphalt and coconut shell ash meet the requirements of The General Highway Specification. Utilization of coconut shell ash filler of 3.5% obtained Optimum Asphalt Content (OAC) of 5.5%, 4% obtained OAC of 5.8%. Based on results of the Marshall parameters for the two mixtures meet all the standards of The General Highways Specification. The use of coconut shell ash as filler in a mixture of road pavements can increase the strength and durability of road pavements, as well as support the realization of green infrastructure. It can have an impact on improving environmental quality through the use of waste for road pavement towards the development of environmentally green infrastructure.

Studi Eksprimental Dengan Metode Marshall Pemanfaatan Plastik Polystyrene Sebagai Bahan Aspal AC-BC

Polystyrene plastic waste is difficult to decompose naturally and becomes microplastics which pollute the environment. Therefore, plastic waste is utilized in road pavement mixtures. This research aims to find out whether the addition of Polystyrene to AC-BC asphalt with levels of 4% and 5% can improve the quality of asphalt based on the 2018 General Bina Marga specifications. This research was carried out in a laboratory and analyzed using the Marshall method. AC-BC asphalt test results with polystyrene content of 4% and 5%, show that only the VIM value at 4% plastic content with a value of 3.88% meets and 5% plastic content with a value of 2.58% does not meet the range of 3%-5%. , then apart from the VIM value of AC-BC asphalt it meets the specifications. Keywords: AC-WC, AC-BC, Polystyrene, Marshall

Bridging Field and Laboratory Permeabilities of Pervious Pavement Mixtures Using XRCT-Based Numerical Modeling

Bridging Field and Laboratory Permeabilities of Pervious Pavement Mixtures Using XRCT-Based Numerical Modeling

KARAYOLU ÜSTYAPI DEĞERLENDİRMESİNDE KULLANILAN TİTREŞİMLERİN ÖLÇÜMÜNDE VÜCUT AĞIRLIĞI VE TAŞIT HIZI ETKİSİNİN İNCELENMESİ

The study delved into investigating the impact of body weight on the determination of vibration parameters, as outlined in the ISO 2631 standard, which elucidates the evaluation concept of Whole Body Vibration. First of all, the ride speed component, which significantly affects the amplitude of the vibration experienced in the vehicle, was determined. In this context, vibration data were recorded at three different points in the vehicle at 20, 30, 40, and 50 km/h ride speeds on a road section whose roughness can be considered homogeneous. Measurements were repeated with drivers weighing 58, 80, and 113 kg to determine the effect of driver weight on vibration parameters. The vibration parameters produced due to the analyses were evaluated with both parametric and non-parametric statistical methods. In the urban road network with bituminous hot mixture pavement, it has been determined that the most appropriate ride speed for passenger car-type vehicles to evaluate the service level of the pavement is 40 km/h. In the last stage, the differences between the averages of the measurements made with three different weight drivers at the determined ride speed were evaluated statistically. Through analysis of three distinct data recording points within the vehicle, it has been established that the driver's weight exerts no discernible influence on any of the vibration parameters.

LITERATURE REVIEW OF COCONUT SHELL AND FIBERS IN PAVEMENT DESIGN

The construction industry faces the challenge to balance the growing demand for new infrastructure and the sustainable use of resources that are generated throughout the different stages of civil infrastructure work. Other industries use materials that leave behind great amount of waste, that often their biodegradation and recycling processes are complex. To find avenues to adapt or incorporate such materials into the productive cycle, characteristics and mechanical properties studies are necessary. For example, due to the large consumption of coconut water, the elimination of these resources has generated major problems such as environmental pollution, methane emissions, insect outbreaks, reduction of the useful life of landfills and increased costs of maintenance of cities. However, several research have demonstrated that coconut fibers and shells may be utilized in concrete applications. This study provides an in-depth review of the literature to learn about the current state of the art in the use of coconut fibers and shells as aggregates in pavement mixtures. Thanks to new technologies, it has been possible to carry out a more in-depth analysis regarding the use of environmentally friendly materials to be used in civil infrastructure works. The incorporation of the shell and coconut fibers are aimed to determine its influence on asphalt mix, considering the amount to be used and its long-term performance and to provide a new technology engineering in the construction of sustainable roads and highways using available ecological material. Researchers propose and agenda for future work for both researchers and practitioners.

Evaluation of the Mechanical Performance of Warm Bio-Recycled Asphalt Mixtures

Currently, approximately 90% of road pavement mixtures are derived from fossil fuels, a major source of the greenhouse gases contributing to global warming. This fact, together with the scarcity of raw materials in pavement engineering, has prompted recent investigations into sustainable alternatives. Biobinders, serving as substitutes or modifiers for petroleum-based asphalt binders, have gained attention, alongside the integration of recycled materials in recycled asphalt (RA). This study addresses these concerns by combining three techniques: (1) substituting a bitumen-based binder with a biobinder; (2) incorporating a high RA percentage (>30%); and (3) manufacturing the asphalt mixture at a reduced temperature (140 °C). These approaches result in the production and evaluation of warm bio-recycled asphalt mixtures. Materials were assessed at both the binder and mixture levels. The control binder, RA binder, and biobinder underwent conventional and rheological characterization. In terms of mixtures, warm bio-recycled asphalt mixtures employed a biobinder as the only virgin binder, with RA contents of 50% and 70%. Mechanical characterization focused on bearing capacity, cohesion, permanent deformations, and moisture damage. The warm bio-recycled asphalt mixtures exhibited adequate outcomes in bearing capacity through the stiffness modulus being 18,120 MPa and 15,683 MPa for bio-recycled asphalt with 50% RA and bio-recycled asphalt with 70% RA, respectively. Bio-recycled asphalt with 50% RA and bio-recycled asphalt with 70% RA showed low permanent deformation percentages, specifically 0.5% and 0.7%, respectively, in comparison to the reference recycled asphalt mixture with 1.5%, allaying concerns in practical applications due to the biobinder’s soft consistency. The bio-recycled asphalt mixture with 70% RA displayed good mechanical performance regarding the studied mechanical characterization, especially exhibiting the least susceptibility to water-induced damage with 97% of the retained indirect tensile strength ratio, addressing concerns related to moisture damage in warm asphalt mixtures with high RA content and biobinders. These findings offer valuable insights into the adoption of more sustainable practices in the asphalt pavement industry, reducing the concerns associated with warm bio-recycled asphalt mixtures.