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One of the most popular rehabilitation methods used for distressed asphalt concrete pavements is use of bonded concrete overlays on asphalt pavements (BCOA). A new procedure, "Bonded Concrete Overlay of Asphalt Mechanistic-Empirical Design (BCOA-ME)," has been developed at the University of Pittsburgh to address significant limitations of similar procedures that have been used by state highway agencies (SHAs) over the years. A portion of the BCOA-ME procedure, renamed Short Jointed Plain Concrete Pavement over Asphalt Concrete (SJPCP/AC), was recently added to AASHTOWare Pavement ME Design (PMED) Software package. Longitudinal fatigue cracking calculated in terms of percentage of slabs is predicted as output distress by the PMED software. This study reports comprehensive sensitivity results for PMED design inputs to predicted longitudinal fatigue cracking. To help understand the impact of climate on the predictions, five climate locations representing different climatic conditions were considered. Normalized sensitivity index (NSI) values were evaluated by performing one-at-a-time (OAT) sensitivity analyses. A summary of results based on evaluated NSI ranking is presented for the varying design periods and reliability levels considered by the PMED software. [ABSTRACT FROM AUTHOR]

In order to improve the basic pavement performance of high-elastic asphalt concrete filled in the expansion longitudinal joints of seamless bridges, rubber particles and polyester fibers were added to optimize the mix proportion of elastic asphalt concrete, and the optimal asphalt–aggregate ratio was determined. The influence of rubber particles and polyester fibers on the basic pavement performance of high-elastic asphalt concrete was studied. The results show that when the dosage of polyester fiber is not more than 0.6%, the optimal asphalt–aggregate ratio is 1:5, and when it exceeds 0.6%, the optimal asphalt–aggregate ratio is 1:4. The incorporation of rubber particles reduces the compressive strength of high-elastic asphalt concrete but enhances its high-temperature stability, fracture performance, and deformation recovery ability. The incorporation of polyester fibers improves its compressive strength, high-temperature stability, fracture performance, and deformation recovery ability. In addition, the incorporation of rubber granules and polyester fibers promotes the use of green building materials and provides strong support for sustainable building practices. [ABSTRACT FROM AUTHOR]

One of the primary causes of premature pavement deterioration in Asphalt Concrete (AC) mixtures is the breaking of the adhesive bond between the aggregate and the binder. The purpose of this study is to assess the performance characteristics of AC mixture utilizing the Rediset LQ-1200 additive. In order to achieve this goal, tests such as the Marshall Stability (MS), Marshall Stability Ratio (MSR), Indirect Tensile (IDT), indirect tensile cracking, and Wheel Tracking (WT) were deployed to evaluate the mechanical properties of AC mixtures. The findings demonstrated a considerable improvement in the physical parameters of the AC mixture with the Rediset LQ-1200 additive compared to the base AC mixture. The MS and MSR were improved by about 28% and 13%, respectively, while the AC mixture's resistance to rutting and cracking was efficiently increased. [ABSTRACT FROM AUTHOR]

The durability of an asphalt concrete pavement largely depends on the quality of the bitumen binder and the strength (or degree) of its interaction with the surface of aggregates (adhesion). The method is based on the finding of bitumen adhesion with a reference substrate, which is taken to be glass. The article presents the results of obtaining the adhesion to the glass surface: bitumen of different grades; bitumen modified with various additives; bitumen modified with adhesive additives and hardened by various methods. The results of comparing the adhesion of bitumen to the glass surface with the results of the Rolling Bottle Test are presented. It has been proved that, with a certain assumption, the value of adhesion to the glass surface can be taken as indicative value for the adhesion of unmodified bitumen to the surface of granite stone materials, obtained after 6 h of testing by the Rolling Bottle Test. [ABSTRACT FROM AUTHOR]

This document discusses the advancements in road engineering, particularly in road pavements and materials. The road pavement sector is gaining attention due to the high number of roads in urban and non-urban areas and the importance of road systems in infrastructure networks. Governments, agencies, and contractors are investing more in pavement engineering, especially in eco-friendly materials and structures. The document covers various topics, including the design and testing of materials, the use of recycled materials, and the management of investments and maintenance. It also explores innovative techniques such as machine learning and artificial intelligence in pavement analysis. The goal of this special issue is to provide valuable scientific contributions and promote further advancements in road engineering. [Extracted from the article]

This paper aims to introduce a highly efficient computational model compared to the current cycle-by-cycle simulation strategy to compute the viscoelastic responses of asphalt concretes and pavement structures under large numbers of load cycles. An explicit constitutive relation for viscoelastic solids in multiple time scales was developed based on the temporal homogenization. The original initial-boundary value problem was divided into a global part in the slow time scale and a local part in the fast time scale. Two simulation studies were presented to validate the computational accuracy and efficiency of the proposed model: (1) a cylindrical asphalt concrete subject to a uniaxial cyclic compression load, and (2) a pavement structure subject to a locally cyclic loading. The laboratory test results and field measurements were compared with the modeled responses to validate the models before comparing with the reference solutions. Results indicate that the temporal homogenization-based viscoelastic model saves considerable computational cost and maintains a satisfactory accuracy. The absolute values of relative error of the modeled responses between the time homogenization and reference solutions are lower than 1% and 4% for the cylindrical asphalt concrete and pavement structure under locally cyclic loadings, respectively. Based on the proposed computational approach, only 4 min are needed to model the response of a cylindrical asphalt concrete subject to 104 repeated load cycles under a uniaxial compression load. The computational time is reduced from 7 h of the reference solution to 38 min of the temporal homogenization solution to model 103 load cycles of a viscoelastic pavement structure. Practical Applications: This study introduces a highly efficient computational model to compute the viscoelastic responses of asphalt concretes and pavement structures under large numbers of load cycles. Multiple time scales were applied to an explicit constitutive relation of asphalt concretes to obtain the formula of global and local initial-boundary value problems. Its computational accuracy and efficiency were verified by comparing the temporal homogenization-based solutions with the testing results and reference solutions for a cylindrical sample and a pavement structure. It is the basis for the long-term pavement performance prediction after including the fatigue damage analysis in the present temporal homogenization framework. By successfully implementing a mechanistic framework for the long-term pavement performance prediction, the pavement design can more rely on the material inherent properties instead of using redundant empirical transfer functions. It is promising that the local calibrations of the current empirical performance transfer functions can be minimized as the proposed pavement long-term performance predictions depend on the material inherent properties and constitutive models. [ABSTRACT FROM AUTHOR]

This study aims to employ the maximum allowed amount of waste materials in the roller- compacted concrete (RCC) mixture using three types of waste materials, namely slag, reclaimed asphalt pavement (RAP) and crumb rubber. A mix design, including recycled materials with the maximum amount allowed to be used in the mixture, is presented by combining alternative materials and covering defects of each alternative material with another alternative material. To make samples containing waste materials, crumb rubber replaces the material passed through the 3/8-inch sieve and remains on sieve no. 50, RAP as the main material replaces coarse aggregates and slag replaces the remaining part of coarse aggregates after RAP replacement. Compressive strength, flexural strength and indirect tensile strength tests are used to evaluate RCC mixture performance. The results indicate increasing RAP decreases indirect tensile strength and increases flexural strength of samples. Moreover, increasing RAP by 50% increases compressive strength and, then, decreases compressive strength if it exceeds 50%. Adding slag to the mixture increases compressive and indirect tensile strength. Also, increasing slag by 50% increases flexural strength of samples and, then, decreases this strength if it exceeds this value. Increasing crumb rubber by 50% decreases compressive strength by 65% and indirect tensile strength of samples by 59.7% compared to the control sample. Increasing crumb rubber by 15% increases flexural strength and, then, decreases this strength if it exceeds this value. Finally, a RCC sample with 70% RAP, 25% slag and 10% crumb rubber is proposed as the final mix design. [ABSTRACT FROM AUTHOR]

The Qinghai–Tibet Plateau shows an obvious trend of warming and humidification, and the increased rainfall is mainly concentrated in the summer. There have been few reports on the effects of summer rainfall variations on the hydrothermal states of embankments in permafrost regions. Therefore, based on an indoor embankment-scale model experiment, the effects of increased summer rainfall on the surface energy, temperature, and water fields of highway embankments in permafrost regions were investigated. The results showed that increased summer rainfall led to an increase in surface net radiation. However, the increase in summer rainfall led to a decreasing trend in the pavement temperature and shallow heat flux of the embankment, indicating that increased summer rainfall could effectively inhibit the increase in pavement temperature. Simultaneously, the increased summer rainfall also increased the shallow water content at different locations of the embankment in the following order: natural site > shoulder > slope > pavement. The maximum increase in water content at the natural site was 6.7% after a twofold increase in the summer rainfall. In addition, the temperature within the embankment exhibited a decreasing trend with an increase in summer rainfall. Compared to other parts of the embankment, although the increased summer rainfall led to a relatively small increase in water content in the lower part of the pavement, the asphalt concrete pavement had a higher temperature. Therefore, when rainfall acts as an energy cold pulse on the pavement, the temperature of the lower part of the pavement decreases more significantly than that of the other parts of the embankment. The increased summer rainfall affected the cooling range of different parts of the embankment in the following order: pavement > natural site > shoulder > slope. The increase in summer rainfall had a hysteresis effect that affected the water and temperature fields within the embankment in autumn. [ABSTRACT FROM AUTHOR]

Asphalt concrete layers deteriorate by traffic, environmental conditions, and material-related properties. While there have been studies on asphalt crack performance, research on fatigue life is still limited since they are mostly based on laboratory experiments. The main objective of this study is to assess the life span and crack performance of an innovative base layer material containing 40% RAP. It is accomplished by analysing the data collected from a constructed test pavement using a full-scale accelerated traffic load simulator MLS10. Significant instrumentation was embedded in the surface and base layers. Experimental campaigns were conducted with around 1 100 000 cumulative load passes applied to the base course under different climatic conditions. Based on the findings, the fatigue life and the crack position are determined for the base layer. Base course material with a recycled binder ratio of 40% survived 800 000 load cycles in severe thermal conditions before crack initiation. [ABSTRACT FROM AUTHOR]

To address the problem related to the service life of Butun rock asphalt concrete pavement under different operating conditions, the fatigue damages of Butun rock asphalt concrete, matrix asphalt concrete, and SBS modified asphalt concrete were ana-lyzed under five types of road environments and different frequencies of repetitive loads by three-point bending repetitive loading tests of Butun rock asphalt concrete beam specimens combined with digital image correlation (DIC) technique. The fatigue damage of Butun rock asphalt concrete, matrix asphalt concrete and SBS-modified asphalt concrete in five road environments were analyzed by DIC technique. The results show that the fatigue life under different road environments and multi-frequency is in the order of SBS-modified asphalt concrete>Butun rock asphalt concrete>base asphalt concrete. The fatigue performance of asphalt concrete is improved by the addition of Butun rock, but the sensitivity to the change of vehicle speed is strong. The fatigue cracking resistance of asphalt concrete is enhanced by the addition of Butun rock. The degree of damage same material under the same number of repetitive loading action decreases with the increase in loading frequency. Butun rock admixture can improve the mixture' s resistance to damage and delay the asphalt concrete appeared accelerated cracking time point. Macroscopic cracks appears when the repetitive loads accounted for 70% of the role of the number of times for Butun rock asphalt concrete. The findings herein can be conducive to the developments of appropriate prevention and control measures in advance in practical projects. [ABSTRACT FROM AUTHOR]

The object of this study is the compaction methods of asphalt mixtures under laboratory conditions. The experience of determining the physical properties of coarse-grained asphalt concretes taken from the layers of the road pavement structure shows that their values do not correspond to those of the samples obtained by laboratory compaction using the pressing method. In 90 % of cases, the density of cores exceeds the density of laboratory samples while the indicators of void content and water saturation are significantly lower than for laboratory samples. The compressive strength indicators of asphalt concrete are almost independent of compaction methods and are not very informative. All of the above leads to the conclusion that the methods of laboratory compaction by pressing do not meet modern requirements. Low values of water saturation and void content of cores and laboratory samples compacted with a gyrator allow us to argue about outdated approaches to the design of grain compositions of asphalt concrete. Low-informative indicators of compressive strength indicate the need to use other mechanical characteristics that will make it possible to predict the properties of asphalt concrete in the pavement, for example, rutting resistance. As a summary, template solutions in the design of asphalt concrete warehouses and physical and mechanical characteristics are necessary only to establish compliance with the requirements of regulatory documents. The current work shows that it is almost impossible to predict the properties of asphalt concrete based on laboratory samples obtained by pressing. All this leads to the need to change the regulatory framework, which is possible by using regulatory documents of the countries in the European Union and the United States of America [ABSTRACT FROM AUTHOR]

This study evaluates the impact of exposing asphalt pavement to sewage and fresh water. In total, 87 samples were prepared, where half of them were immersed in sewage and the others were immersed in freshwater. The Marshall mix design method was adopted for the preparation of samples. Three immersed samples were tested for stability and flow every 24 hours in both fresh water and sewage, comparing the results with a control sample. The samples immersed in fresh water lost their stability and flow after 11 days, while the ones immersed in sewage water lost their stability and flow after 9 days. Furthermore, the loss in stability for samples immersed in fresh water and sewage after 14 days was found to be 38.8 and 55.6%, respectively. The results revealed that sewage water affects asphalt concrete pavement more severely than freshwater. Finally, it was concluded that proper drainage and adequate supplemental sewerage systems are necessary to maintain the desired strength of the pavement throughout its design life. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article discusses the concept of byproduct synergy (BPS) in the context of water and wastewater infrastructure projects. BPS involves matching waste or byproduct streams from one facility with potential uses at another facility to create new revenues or savings with social and environmental benefits. The Envision sustainability framework and rating system encourages project teams to consider byproduct use and identify opportunities for beneficial reuse. The article provides examples of BPS in projects involving wastewater biosolids, fly ash in concrete design, and the reuse of materials in construction. The article emphasizes the importance of investigating opportunities for beneficial reuse to promote sustainability in the water industry. [Extracted from the article]

While several research studies considered the utilization of reclaimed asphalt pavement (RAP) aggregates for asphalt and concrete pavements, very few attempted its possible utilization for precast concrete applications like concrete paver blocks (CPBs). Moreover, few attempts made in the recent past to improve the strength properties of RAP inclusive concrete mixes by incorporating certain supplementary cementitious materials (SCMs) have reported an insignificant or marginal effect. The present study attempts to comprehensively investigate the utilization potential of some locally and abundantly available materials having suitable physicochemical properties to improve the performance of a zero-slump CPB mix containing 50% RAP aggregates. The studied filler materials, namely, wollastonite (naturally occurring calcium metasilicate mineral) and jarosite (hazardous zinc industry waste), were used to replace 5–15% and 10–20% by volume of Portland cement in the 50% RAP CPB mix. Apart from their individual effects, the efficacy of wollastonite-jarosite blends was also investigated. Considering the lack of indoor storage facilities and economic aspects of CPBs, the influence of water spray curing regime on the performance of the RAP CPB mixes was studied and compared to that of continuous water curing regime. Inclusion of the considered fillers was found to statistically and significantly enhance the flexural strength, tensile splitting strength, and abrasion resistance of the 50% RAP CPB mix; however, the compressive strength (in most cases), permeable voids, water absorption, and water permeability properties showed an insignificant improvement. Results of thermogravimetric analysis confirmed the occurrence of pozzolanic reactivity, and microstructure analysis revealed improvements in packing of concrete matrix and ITZ with filler inclusion qualitatively substantiating the improvements in strength and durability characteristics. The toxicity characteristics of heavy metals that may leach from the hazardous jarosite-based RAP CPB mixes were found to be within permissible limits. Based on the performance requirements specified by IS, IRC, and ASTM standards, all the RAP CPB mixes with filler inclusions fulfilled the acceptance criteria for heavy traffic applications, and water spray curing can enact as an alternate method for curing these mixes. However, to avail maximum performance benefits, it is recommended to use 5% wollastonite, 15% jarosite, and a combination of 10% wollastonite and 10% jarosite as a Portland cement substitute to produce sustainable eco-friendly RAP CPB mixes. [ABSTRACT FROM AUTHOR]

The prediction of strain responses under axle loadings is critical for flexible pavement design by the mechanistic-empirical approach. The mechanistic-empirical pavement design (pavement ME) method uses linear-elastic analysis to simulate the strain responses under axle loadings, and it relies on the concept of equivalent loading frequency to determine the elastic modulus of the asphalt concrete (AC) layer from the dynamic modulus master curve. The pavement ME method has a simplified procedure to calculate this frequency. The main goal of this study is to evaluate the accuracy of axle loading frequency calculated by the pavement ME method. This paper first introduces the concepts of predominant and equivalent frequencies, provides a brief explanation of the difference between them, and then proposes three predominant frequency methods for evaluation. The accuracy of the pavement ME method and the other methods of calculating the predominant frequency is evaluated in terms of frequency, modulus, and strain by comparing their results with those from dynamic viscoelastic analysis with moving loads. Results show that the time–frequency relationship for predominant frequency is closer to f=1/(2t) than f=1/t , assuming that the pulse duration t is accurate. Nevertheless, using f=1/t with the approximate pulse duration as calculated by the pavement ME method gives reasonable predictions of the maximum tensile strain. On the other hand, while it gives reasonable predictions of vertical strains with increasing depth, the pavement ME method can underestimate them near the surface by up to 55%. Overall, even though the procedure for pavement ME frequency calculation is highly simplified, its general performance appears to be acceptable. The two most typical distresses of flexible pavement are rutting and fatigue cracking, and they are related to two critical strains: vertical strains throughout the layers and horizontal strains at the bottom of the asphalt concrete later of the pavement. The commonly used design approach, the pavement ME method, utilizes the concept of equivalent loading frequency to predict critical strains within the pavement by linear-elastic analysis rather than the full dynamic viscoelastic analysis. This reduces the computational cost significantly. This paper investigates the accuracy of the equivalent loading frequency calculated by the pavement ME method by comparing the frequency values with several other methods, and, finally, comparing the critical strains predicted by the pavement ME method and the results from dynamic viscoelastic analysis, which is considered to be the truth. The results showed that the pavement ME method underestimates vertical strains near the surface of the pavement, which may lead to underestimating rutting (before calibration). However, calibration may be able to remedy the problem. On the other hand, the horizontal strain predicted by the pavement ME method is reasonable, which means the fatigue cracking can be reasonably predicted. [ABSTRACT FROM AUTHOR]

Most of the roads in Algeria are flexible pavements, the main component of which is asphalt concrete. Asphalt concrete aggregates made from crushed stone are now expensive and unavailable near roads, favoring the use of local materials such as dune sand, which is abundant in southern Algeria. The aim of this work is to study the rheological behavior of asphalt concrete, which is partially made of dune sand, as an alternative to crushed sand currently used. The effect of dune dosage on the rheological properties of concrete, in particular its compaction and rutting resistance, was determined using several formulations. To this end, various asphalt mixtures were tested on different dune sand grains using the Super pave rotary shear compaction (GSC) test by means of a rotary shear press to quantify their effect on compaction. These same asphalt mixtures were used to manufacture inserts for rutting tests. According to the results obtained, very acceptable values of resistance to rutting were achieved with 05 to 15% of dune sands compared to the reference concrete. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Asphalt overlay is widely used in maintaining and rehabilitating highway system performance. However, explicit calculation methods for the asphalt overlay thickness range is lacking. Taking stone mastic asphalt (SMA) and asphalt concrete (AC) asphalt overlay on cement concrete pavement as examples, the paper proposed a design method for the asphalt overlay thickness range based on the shear performance of the interlayer. Firstly, the shear stress distribution regularities on the asphalt overlay and Portland cement concrete interlayer was calculated with a multilayer elastic theory. Meanwhile, the shear strength was obtained from a series of direct shear tests. The shear characters of the asphalt overlay met with the Mohr–Coulomb criterion, and the shear strength parameters cohesive force c and interface friction angle φ on the interlayer were acquired. Finally, a method for determining the thickness range of double layer asphalt overlay under different traffic conditions was given. The epoxy resin adhesive was recommended for the highway with severe local premature shear failure compared with the modified emulsion asphalt. Therefore, through the above research, the amount of asphalt used is controlled in a reasonable range, thus improving the pavement structure durability and reducing energy consumption. [ABSTRACT FROM AUTHOR]

Purpose: The time-varying equivalent linear temperature gradient (ELTG) significantly affects the development of faulting and must therefore be accounted for in pavement design. The same is true for faulting of bonded concrete overlays of asphalt (BCOA) with slabs larger than 3 x 3 m. However, the evaluation of ELTG in Mechanistic-Empirical (ME) BCOA design is highly time-consuming. The use of an effective ELTG (EELTG) is an efficient alternative to calculating ELTG. In this study, a model to quickly evaluate EELTG was developed for faulting in BCOA for panels 3 m or longer in size, whose faulting is sensitive to ELTG. Design/methodology/approach: A database of EELTG responses was generated for 144 BCOAs at 169 locations throughout the continental United States, which was used to develop a series of prediction models. Three methods were evaluated: multiple linear regression (MLR), artificial neural networks (ANNs), and multi-gene genetic programming (MGGP). The performance of each method was compared, considering both accuracy and model complexity. Findings: It was shown that ANNs display the highest accuracy, with an R2 of 0.90 on the validation dataset. MLR and MGGP models achieved R2 of 0.73 and 0.71, respectively. However, these models consisted of far fewer free parameters as compared to the ANNs. The model comparison performed in this study highlights the need for researchers to consider the complexity of models so that their direct implementation is feasible. Originality/value: This research produced a rapid EELTG prediction model for BCOAs that can be incorporated into the existing faulting model framework. [ABSTRACT FROM AUTHOR]

The current standard for evaluating road conditions worldwide relies primarily on the Pavement Condition Index (PCI) and the International Roughness Index (IRI). The IRI can be further calculated to obtain the Riding Quality Index (RQI). To assess pavement damage, various imaging equipment is commonly utilized, providing consistent results that align with actual road conditions. For roughness detection, the Laser Profilometer offers excellent results but may not be suitable for rural roads with poor conditions due to its high inspection cost and the need for a stable environmental setting. Therefore, there is a pressing need to develop cost-effective, rapid, and accurate roughness inspection methods for these roads, which constitute a significant portion of the road network. This study examined the relationship between PCI and RQI using nonlinear regression on 30,088 valid pavement inspection records from various regions in China (totaling 24,624.222 km). Our objective was to estimate RQI solely from PCI data, capitalizing on its broad coverage and superior accuracy. Additionally, we explored how PCI levels impact RQI decay rates. The models in this study were compared to several models published in previous studies at last. Our findings indicate that the model performs best for low-grade roads with low PCI scores, achieving over 90% accuracy for both cement concrete and asphalt concrete pavements. Furthermore, different levels of pavement damage have distinct effects on RQI decay rates, with the most significant impact observed when the pavement is severely damaged. The models in this study outperformed all the other available models in the literature. Consequently, under limited inspection conditions in rural areas, pavement damage inspection results can effectively predict riding quality or roughness, thereby reducing inspection costs. Overall, this study offers valuable insights but has limitations, including limited global generalizability and the model's applicability to high-grade roads. Future research is needed to address these issues and enhance practical applications. [ABSTRACT FROM AUTHOR]

The rehabilitation of deteriorated pavements using Asphalt Concrete (AC) overlays consistently confronts the reflection cracking challenge, where inherent cracks and joints from an existing pavement layer are mirrored in the new overlay. To address this issue, the current study evaluates the effectiveness of Engineered Cementitious Composite (ECC) and geotextile fabric as mitigation strategies. ECC, characterized by its tensile ductility, fracture resistance, and high deformation capacity, was examined in interlayer thicknesses of 7, 12, and 17 mm. Additionally, the impact of geotextile fabric positioning at the base and at 1/3 depth of the AC specimen was explored. Utilizing the Overlay Testing Machine (OTM) for evaluations, the research demonstrated that ECC17 significantly mitigated reflection cracking, showing a notable 764% increase in the number of load cycles to failure (Nf) compared to the Geotextile Base (GB) specimen. Against the Reference Specimen (RS), ECC17 exhibited a remarkable 1307% enhancement in Nf values, underscoring its effectiveness. Geotextile fabric, particularly at 1/3 depth, demonstrated notable resistance but was overshadowed by the performance of ECC interlayers. The results clearly indicate that ECC, especially ECC17, stands out as an effective solution for mitigating reflection cracking, including joints, in AC overlays. [ABSTRACT FROM AUTHOR]

Based on the general Marshall design method for asphalt mixtures, the difference of asphalt mixture density was determined according to the mechanical design method and volume design method. To improve the control accuracy of asphalt concrete pavement density, two design methods were established to determine the correlation of asphalt mixture density. In this study, samples were divided into original, core, and road core samples and selected as the research objects. First, the core samples of original asphalt concrete were formed and drilled by gyratory shear compacting press (PCG) compaction and core-drilling equipment in laboratory tests. Second, the density and volume indicators calculated by the quality of the original and core samples were measured according to the water gravimetric method. A correlation between the testing and the core samples could be established for the original samples. Finally, the corresponding data of the core samples obtained by Marshall test were compared with the data of mechanical design method. Test results show that the density and saturation of original samples increased by 1.4% and 9.8% compared with core samples, and inversely, the porosity and mineral gap ratio reduced by 24.8% and 7.6%. Data of the original and the core samples have a linear relationship and the correlation coefficients of density, porosity, saturation, and mineral gap ratio are 0.979, 0.975, 0.968, and 0.982, respectively. The optimum asphalt content of the Marshall test core samples is consistent with that of the gyratory testing machine (GTM) test; the density and volume index of the core samples are between the GTM and the Superpave test data. In conclusion, the degree of road compaction could be evaluated by the Marshall core samples more accurately than that of the original samples. For the units or areas without sufficient equipment for mechanical design of asphalt mixture, the density of Marshall core sample could be suggested to use for the detection and evaluation of asphalt pavement. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Autonomous vehicles (AVs) movement in a narrower traffic lane and anticipated climate change are crucial for asphalt concrete (AC) pavement distress. This study assesses the combined effect of AVs and climate change on the performance of AC pavement for a road section in Ontario, Canada. The performance of AC pavement due to AVs and climate change has been evaluated using the AASHTOWare Mechanistic-Empirical (ME) pavement design. AVs were incorporated in ME pavement design using traffic factors such as adjusting traffic volume with the load equivalency and lane distribution factors. This analysis was carried out to determine the individual and combined influence of AVs and climate change on pavement performance. This study determines the combined impacts of AVs and climate change by comparing pavement performances for human-driven vehicles with historical climate and AVs with projected climate. The comparative performance analyses of human-driven vehicles and AVs with projected climate demonstrated the effect of climate change. AVs and climate change combinedly and AVs alone accelerate the accumulation of AC rutting and bottom-up fatigue cracking. The regulation of AVs explicitly to ensure uniform loading distribution and the placement of AVs with non-AVs in a controlled manner were the best alternatives to minimise pavement distress. [ABSTRACT FROM AUTHOR]

There are several methods for determining the stiffness of asphalt concrete in an existing pavement. The three primary methods are dynamic modulus testing in the laboratory, predictive equations, and falling weight deflectometer (FWD) testing. The Pavement ME asphalt over asphalt (AC/AC) overlay design procedure uses multiple methods to characterise fatigue damage in the existing asphalt concrete. This paper examines the relationship between backcalculated dynamic modulus, estimated dynamic modulus, and fatigue damage in in-situ asphalt concrete. FWD load magnitude and asphalt temperature, both of which have been shown to affect the relationship between backcalculated and estimated dynamic modulus, are also considered. A statistical analysis is performed using data from the Long-Term Pavement Performance Programme (LTPP). Analyses are performed within individual LTPP sections and using pooled data from multiple pavement sections. It is determined that the relationship between backcalculated dynamic modulus and estimated dynamic modulus is significantly related to the amount of fatigue damage in the in-situ asphalt concrete. However, there is also a threshold of fatigue damage above which the relationship between backcalculated modulus, estimated modulus, and fatigue damage is no longer significant. [ABSTRACT FROM AUTHOR]

The scope of this study was to assess the predicted impact of design factors (voids percentage (Va), effective binder content (Vbe) and aggregate gradation) in each asphalt concrete (AC) layer on pavement performance for conditions in Izmir, Turkey. Research was conducted on three flexible pavement structures for three traffic levels and three subgrade types using AashtoWare Pavement ME Design software. The results indicated that increasing Vbe (from 8% to 15%) and Va (from 3% to 5%) in the wearing course resulted in, respectively, almost 1.0 mm and 0.2 mm increases in AC rutting depth, 17 m/km and 145 m/km reductions in thermal cracking length and a 55.8 m/km decrease and 85 m/km increase in top-down cracking length. For the binder course, an increase in Vbe (from 7% to 14%) and Va (from 4% to 6%) led to, respectively, nearly 1.0 mm and 0.3 mm increases in AC rutting depth and a 35 m/km increase in top-down cracking length. For the AC base course, an increase in Vbe (from 6% to 12%) and Va (from 5% to 6%) resulted in a 26.3% reduction and 14.2% increase in alligator cracking area, respectively. An increase in the fine aggregate percentage and a decrease in the coarse aggregate gradation in the hot-mix asphalt mixture led to improved performance. [ABSTRACT FROM AUTHOR]

Freeze–thaw cycles in seasonal permafrost areas are a dominant cause of road damage. Therefore, the roadbed fill must be frost-resistant. In this study, taking the experimental section of the asphalt concrete pavement structure of the Zhangcheng Expressway in the seasonally frozen soil area of Hebei Province as an example, three working conditions were selected: a low embankment with a waterproof geotextile partition layer, a low embankment with a gravel layer + extruded polystyrene (XPS) board, a high embankment with a gravel layer + two pieces of cloth, and a waterproof geomembrane. After 2 years of tracking and analysis of the measured data, the subgrade temperature distribution law was derived in terms of time and depth to obtain the freezing depth under each working condition. The experimental results showed that the gravel bedding layer, XPS plate, and geosynthetic materials had a significant effect on the prevention and mitigation of road disease, and therefore, their application must be promoted. [ABSTRACT FROM AUTHOR]

Asphalt binders have been studied extensively with respect to their linear viscoelastic properties. From these properties, performance metrics have been derived and used for specification purposes. However, these materials are used in asphalt concrete pavements where they may experience time-dependent loads in the nonlinear regime. In the past, the vast majority of asphalt binders exhibited strong correlations between their linear and nonlinear properties and so despite this mismatch in characterization and the actual use phase domains, a system based on linear properties could be reliably deployed. More recently though, novel binders and additives have been introduced with differing relationships between linear and nonlinear behaviors. As such there is a need to characterize the asphalt binder response under large strains and use specifications that more explicitly account for the binder nonlinearity. Here, an attempt has been made to characterize the nonlinear rheological properties of asphalt binder using large amplitude oscillatory shear. The response of a single terminal blend, crumb rubber modified binder under large strains is analyzed using Lissajous-Bowditch plots while the contribution of higher harmonics is evaluated using Fourier-transform rheology. Finally, the elastic and viscous contributions are obtained using stress decomposition to an orthogonal set of Chebyshev polynomials. It is found that the relative nonlinearity increases with increasing strain and frequency under the tested conditions. The asphalt binder evaluated in this study predominantly exhibits shear thinning and either strain stiffening or softening behavior depending upon the test conditions. The applicability of time-temperature superposition in the nonlinear regime for asphalt binders is also evaluated. [ABSTRACT FROM AUTHOR]

The study is aimed to mathematically model the relationship between the amount of whole-body vibration exposed in a passenger car type vehicle and the ride speed of the vehicle in the same section and the International Roughness Index (IRI), which is used as a pavement performance indicator. Vibration measurements were analysed according to the evaluation method determined in the ISO 2631 standard, and frequency-weighted root-mean-square acceleration (aw) values were obtained in the vertical direction. Mathematical relationships between real measurement data performed in 1114 road sections were investigated using regression analysis, artificial neural networks (ANN) and Adaptive Neural Fuzzy Inference System (ANFIS) modelling techniques. The models' performance levels were determined using comparison metrics, and it was determined that ANFIS was the model with the best goodness of fit, with the regression coefficient 0.955, mean absolute error (MAE) 0.013, and root mean squared error (RMSE) 0.020. The threshold values affecting the ride comfort of IRI and the ride comfort values corresponding to the IRI limit values recommended by the Federal Highway Administration (FHWA) were determined through the ANFIS mathematical model. Then, a sensitivity analysis was conducted to determine the effects of a certain increase in the IRI value on discomfort. [ABSTRACT FROM AUTHOR]

Waste glass is an endless issue for the majority of the countries in the world with a linear economy of usage of materials. Demolition waste is counted as part of total construction and demolition waste (CDW). Even today, there are some statistical problems with the quantification of demolition waste and dividing it from total CDW, since most countries do not provide such a division of waste types. The current review shows possible ways of utilizing waste glass in some useful products in the construction industry. It is elaborated using PRISMA@ methodology with bibliometric and qualitative methods to provide a systematical overview of the publications in the period from 2000 to 2023. The bibliometric search was handled with the application RStudio© using sources in the biggest database, Scopus. Most of the published research items are mainly focused on using waste glass in concrete applications. However, there are seven possible areas of waste glass application in the construction industry: concrete products, gypsum–cement composites, asphalt or concrete pavement, geopolymer mortars, foamed glass ceramics, glass ceramics, and soil foundation strengthening/stabilization. In its turn, the circular economy should be applied since it provides a prolonged turnaround of materials throughout their life cycle. [ABSTRACT FROM AUTHOR]

Interface shear stiffness modulus (K) is one of the important bonding properties of layers. It is also used to evaluate interface shear strength between asphalt layers of asphalt pavement. Direct determination of K parameter in field or laboratory requires time, cost and special equipment. In this article, K has been estimated based on three interlayer shear strength affecting factors namely maximum size of the asphalt concrete aggregate (Dmax), normal pressure and temperature using Machine Learning (ML) methods such as Multilayer Perception Neural Network, Bagging Random Forest (Bagging-RF), and Bagging Reduced Error Pruning Tree (Bagging-REPT). The ML models for the prediction of shear strength were built based on the laboratory shear tests results of 180 double-layer asphalt samples. The data was divided randomly into a ratio of 70/30 to train and test model, respectively. Standard statistical measures were used to evaluate and validate the models' performance. All the developed models performed well in correctly predicting K value of AC, but performance of the Bagging-RF model is the best as it is giving Correlation Coefficient (R) value 0.88 between estimated value and determined value. The proposed ML predictive models will reduce the field and laboratory experimental efforts and increase the efficiency in estimating the K parameter for the safe designing, construction and maintenance of asphalt concrete pavements. [ABSTRACT FROM AUTHOR]

This study experimentally investigates the usability of asphalt concrete pavement containing five different ratios of graphite powder (0%, 1.25%, 2.5%, 3.75% and 5% by weight of the aggregate blend or 0%, 25%, 50%, 75% and 100% of the filler content) as a filler to be potentially used as part of wireless electric roads (ER). As part of the study, first, optimum asphalt binder content for the asphalt mixes without graphite powder was determined as 5%. Then, using the determined optimum asphalt binder content, asphalt mixes containing five different ratios of graphite powder as a filler were prepared and their mechanical and volumetric properties based on Marshall mix design methodology were evaluated. As graphite powder ratios in the asphalt mixes increased, their Marshall stability, flow, voids filled with asphalt and unit weight test results mostly decreased but their air content and voids in mineral aggregate test results increased. Possible reasons for this could be: (1) lower bulk specific gravity of graphite powder, (2) higher asphalt absorbance, (3) having greater surface area compared to that of limestone filler, and (4) weak bonds between sheet-like graphite layers. Furthermore, another batch of asphalt mixes containing five different ratios of graphite powder were prepared and tested in the frequency range of 3-18 GHz for their electromagnetic permittivity properties. It was observed in this study that, except for the specimens with 100% graphite powder ratios, transmission magnitudes of all specimens were above 50% up to 8 GHz, indicating that they had comparably high transmission magnitudes so as comparably low tangent loss values. In the frequency range of 3-13 GHz, transmission magnitudes of the specimens with 25% and 50% graphite powder ratios were consistently higher than that having no graphite powder, the ones with 25% powder ratios had the highest transmission magnitudes in most of the cases in this frequency range. Considering the mechanical, volumetric and electromagnetic property test results of the asphalt mixes with five different ratios of graphite powder, it can be concluded that the use of 25% graphite powder ratio (corresponding to 1.25% of the aggregate blend used in the mixes), has a comparably lower negative effect on mechanical and volumetric properties of asphalt mixes and has a positive effect on electromagnetic permittivity properties of asphalt mixes. Asphalt mixes produced with this graphite powder ratio can be considered to be used as part of wireless ER. [ABSTRACT FROM AUTHOR]

As the total mileage of roads with asphalt concrete pavement is increasing rapidly, using ground-penetrating radar (GPR) to estimate the dimension of internal distresses of the asphalt pavement is of great significance for pavement maintenance. However, the relationship between the dimension of road distress and the characteristics of road distress's radar echo has not been quantified. Therefore, in this paper, a GPR forward modeling toward base cracks and interlayer voids is conducted to investigate the relationship, and a model test is conducted to verify the forward modeling. The results indicate that it is feasible to use a GPR image to estimate the dimension of interlayer voids and base cracks. For vertical dimension estimation, the vertical dimension of the distressed area has a positive relationship with the difference in the return time of radar echoes from the top and bottom of the distressed area. However, the area's vertical dimension must be at least a quarter of the length of the electromagnetic wave used in the GPR to be correctly identified. Otherwise, it is not easy to distinguish the overlapping echoes from each other. For horizontal dimension estimation, the base crack's horizontal dimension has a quadratic correlation with the echo's amplitude, and the horizontal dimension of an interlayer void is approximately equal to the length of its echo's flat segment. [ABSTRACT FROM AUTHOR]

The results of high-precision asphalt concrete pavement crack identification can provide help for pavement maintenance. Therefore, methods of image feature enhancement and crack identification of asphalt concrete pavement cracks are proposed. First of all, we used an industrial CCD camera mounted on a vehicle to collect an asphalt concrete pavement crack image. Then, after using the NeighShrink algorithm to denoise the acquired image, a fractional differential image enhancement algorithm was designed based on image feature blocks to enhance the image features. On this basis, crack characteristics were segmented and processed by watershed algorithm. Through crack direction identification and crack parameter extraction, crack distribution direction, crack length and width and other parameters of asphalt concrete pavement were obtained in order to achieve accurate identification of asphalt concrete pavement cracks. The experiment found that this method can effectively remove noise information from asphalt concrete crack images; after applying this method, the image entropy value of each image was improved, with a minimum improvement of 0.38 and a maximum improvement of 1.98. The time consumed by this method in identifying cracks in asphalt concrete pavement varied between 1.4 s and 2.4 s. When identifying the length of cracks in asphalt concrete pavement, the maximum deviation value was only 0.47 mm; when identifying the width of cracks in asphalt concrete pavement, the maximum deviation value was only 0.31 mm. The above results indicate that by enhancing the image features of asphalt concrete cracks, this method achieves more accurate identification results for crack distribution direction, length and width values, with high identification efficiency and good application effect. [ABSTRACT FROM AUTHOR]

The settlement in permafrost regions has a significant effect on the safety of the aircraft. Therefore, a numerical model of asphalt concrete pavement and subgrade in permafrost regions is proposed and verified by comparing with previous studies. Numerical models under the dynamic load of aircraft are used to analyze the settlement nephogram, time-dependent curve, and settlement curve. Results show that the influences of different parameters on settlements decrease slowly at the depth of 0–1.45m, then decrease quickly at the depth of 1.45-2m, finally tend to be stable. The peaks of settlements increase with the growth of international roughness index, taxiing speed, and aircraft's weight. The settlement increases little when the international roughness index is more than 3. The settlement varies significantly when the taxiing speed is from 30m/s to 70m/s. The study provides a theoretical basis for the construction and maintenance of asphalt concrete pavement and subgrade in permafrost. [ABSTRACT FROM AUTHOR]

Growing traffic loads, soaring summer temperatures, and moisture damage will render conventional asphalt binder insufficient to maintain the performance standards of asphalt concrete pavement. Thus, it is necessary to modify the virgin asphalt using various polymers or nanomaterials. The primary goal of this research was to examine the rheological effects of combining multiple-walled carbon nanotubes (MWCNTs) and styrene butadiene styrene (SBS) in an asphalt binder. In this study, MWCNTs and SBS were mixed with virgin asphalt at concentrations of 1%, 3%, and 5% by weight. The performance grade (PG) and asphalt binder qualities were determined through Superpave system testing. The addition of 1% MWCNTs had no effect on the (PG) of virgin asphalt, whereas the addition of 3% and 5% MWCNTs resulted in increases of 2° and 4°, respectively. When 1% SBS is added to asphalt, the PG rises by an average of 1°; when 3% and 5% SBS are used, the PG rises by an average of 2° and 3°, respectively. The results also showed that the rutting parameter (G ∗ /sin) increased by 10%, 73%, and 208% when asphalt was changed with 1%, 3%, and 5% of SBS, and by 18% and 130% when MWCNTs were applied. [ABSTRACT FROM AUTHOR]

Concern exists regarding the performance of concrete containing a higher percentage of recycled aggregates. There is an ongoing effort to improve the strength and durability characteristics of such concrete in various ways. As part of that effort, this study investigated the laboratory performance of geopolymer concrete containing a higher dosage of reclaimed asphalt pavement (RAP) as a pavement construction material. A series of laboratory investigations were performed to evaluate the mechanical, durability, and morphological characteristics of RAP-geopolymer concrete (GPC). The mechanical properties of RAP-geopolymer concrete were also compared with RAP-Portland cement concrete (PCC) produced using ordinary Portland cement (OPC). Results indicated that RAP-geopolymer concrete exhibited higher compressive, flexural, split tensile strength as compared to RAP-cement concrete. Further, RAP-geopolymer concrete revealed satisfactory results in terms of durability regarding wet–dry cycles and water absorption (sorptivity). Morphological and microstructural investigation using scanning electron microscopy (SEM), X-Ray diffraction (XRD), and Fourier-transform infrared spectroscopy (FTIR) also discovered the formation of geopolymer compounds in RAP-geopolymer concrete which explains the better mechanical and durability properties of such concrete mixtures. [ABSTRACT FROM AUTHOR]

This study addresses the challenges of overlaying old concrete pavement with asphalt by introducing a new trackless tack coat material containing polymer. The aim is to enhance the durability of asphalt concrete overlay pavement on old cement concrete pavement. It contributes to the development of improved construction techniques for pavement rehabilitation and highlights the need for reliable adhesion performance evaluation based on different spray amounts and surface conditions. Additionally, to evaluate the effect of the adhesion performance based on the spraying amount, a tensile adhesion test was conducted by applying spray amounts of 0.30, 0.45, and 0.60 l/m2 on different surface conditions. The basic and adhesion performances of the polymer-modified tack coat material are evaluated through direct tensile and shear bond strength tests. The test outcomes demonstrated that the newly developed polymer-modified tack coat material had considerably greater adhesion strength compared to the traditional rapid-setting products. Its adhesive strength was 1.68 times higher on concrete and 1.78 times higher on asphalt. The new trackless tack coat material exhibited an adhesion performance of 1.05 MPa in direct tensile strength at 0.45 l/m2, which was 1.21 times higher than the rapid-setting tack coat. Results also confirmed that the new tack coat material exhibits values 1.90 times greater than the conventional rapid-setting tack coat material in shear bond strength, respectively. By simulating the process of separation and re-adhesion of pavement layers caused, the new tack coat material shows a tensile adhesion strength of 63% of the original state, which is advantageous for securing the durability of the pavement. Overall, the newly developed polymer-modified trackless tack coat has been shown to effectively enhance the adhesion performance between pavement layers without process delay, highlighting the potential of the new tack coat material to enhance the durability of asphalt concrete overlay pavement on old cement concrete pavement. [ABSTRACT FROM AUTHOR]

Understanding the vibration response patterns of aircraft taxiing under runway roughness excitation is crucial for aircraft design and runway performance evaluation. In this paper, we establish pavement roughness models for both asphalt and concrete surfaces, taking into account their unique structural characteristics. We construct a six-degrees-of-freedom aircraft model using multi-rigid-body system dynamics theory and employ the pseudo-excitation method to examine the influence of pavement roughness types on the steady vibration response of aircraft taxiing at constant speeds. Furthermore, we analyze the non-stationary vibration response patterns of aircraft during takeoff and landing taxiing using the method of instantaneous frequency response function with space frequency. Lastly, we explore the effect of stochastic structural parameters on aircraft vibration response using the Monte Carlo method. Our findings reveal that the roughness power spectrum differs between asphalt and concrete pavements, and the established roughness models in this paper demonstrate a strong fit (R2 > 0.95). The type of pavement roughness has a relatively minor impact on the power spectral density distribution of the aircraft vibration response, suggesting that the same roughness model can be used for both asphalt and concrete pavements when high accuracy is not required. The power spectral density distribution of aircraft vibration response varies across different motion attitudes, with the vibration response during landing being significantly larger than that during takeoff. Among the aircraft structural parameters, the randomness of the sprung mass has the most substantial effect on the aircraft vibration response, potentially causing the variation coefficient of dynamic load on the front landing gear to exceed 0.11. Tire stiffness comes next, which can lead to the variation coefficient of dynamic load on the main landing gear reaching 0.07. The results have a guiding role in optimizing aircraft structure design and ensuring pavement performance. [ABSTRACT FROM AUTHOR]

Semi-flexible pavement material (SFPM) combines the advantages and avoids the disadvantages of asphalt concrete flexible pavement and cement concrete rigid pavement. However, due to the problem of interfacial strength of composite materials, SFPM is prone to cracking diseases, which limits the further application of SFPM. Hence, it is necessary to optimize the composition design of SFPM and improve its road performance. In this study, the effects of cationic emulsified asphalt, silane coupling agent and styrene–butadiene latex on the improvement of SFPM performance were compared and analyzed. The influence of modifier dosage and preparation parameters on the road performance of SFPM was investigated by an orthogonal experimental design combined with principal component analysis (PCA). The best modifier and the corresponding preparation process were selected. On this basis, the mechanism of SFPM road performance improvement was further analyzed by scanning electron microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) spectral analysis. The results show that adding modifiers can significantly enhance the road performance of SFPM. Compared to silane coupling agents and styrene–butadiene latex, cationic emulsified asphalt changes the internal structure of cement-based grouting material and increases the interfacial modulus of SFPM by 242%, allowing cationic emulsified asphalt-SFPM (C-SFPM) to exhibit better road performance. According to the results of the principal component analysis, C-SFPM has the best overall performance compared to other SFPMs. Therefore, cationic emulsified asphalt is the most effective modifier for SFPM. The optimal amount of cationic emulsified asphalt is 5%, and the best preparation process involves vibration at a frequency of 60 Hz for 10 min and 28 days of maintenance. The study provides a method and basis for improving the road performance of SFPM and a reference for designing the material composition of SFPM mixes. [ABSTRACT FROM AUTHOR]

Nanomaterials have shown great potential in improving the mechanical and rheological properties of asphalt binders based on laboratory examination. Some nanomaterials were reported to improve asphalt binders' resistance to aging. This paper investigates the effect of adding different contents of nanoclay and nanosilica to asphalt binders on short-term aging and simulated pavement performance using AASHTOWare Pavement ME Design. The rheological properties of a conventional asphalt binder as well as modified asphalt binders with different percentages of two different nanomaterials, namely, nanoclay and nanosilica, were measured in the laboratory. An aging index based on Superpave rutting parameter was calculated. A matrix of 84 simulations was developed to evaluate the effect of these nanomaterials on the predicted flexible pavement distresses under three different climate conditions and two asphalt concrete (AC) thicknesses with different percentages of two types of nanomaterials. The simulated performance results were analyzed using statistical tools to determine the most significant parameters and the significance of the interaction between these parameters. Results showed that both nanomaterials can significantly improve the pavement resistance to aging, permanent deformation, fatigue cracking, and roughness. The results of the simulations showed that there is no unique nanomaterial content that can be considered optimum for all climatic conditions. All the investigated nanomaterials have shown extended simulated pavement life for different pavement structures and climatic conditions except the case of nanosilica for thin AC under moderate climatic condition. Finally, both nanomaterials' content and type were found to have significant effects on the investigated distresses with the nanomaterial content ranked higher than the nanomaterial type in rutting and fatigue prediction and the opposite for international roughness index (IRI). Recently, the well-known AASHTOWare Pavement ME Design software has been used by many engineers, contractors, and highway agencies to perform pavement structural design based on a mechanistic-empirical pavement design approach. Comparing the laboratory testing results for nanomodified asphalt binders with conventional asphalt binder can help decision makers translate the laboratory results to actual field performance in terms of known pavement distresses such as rutting, fatigue cracking, and international roughness index (IRI). Several scenarios were investigated in this study varying the structure (thin and thick sections), material properties (control asphalt and nanoclay- and nanosilica-modified asphalts), nano content (0%, 3%, 5%, and 7%), climate (cold, moderate, and hot), and binder grading system (conventional and Superpave) in the software with 84 computer simulation runs. Nanoclay and nanosilica were found to improve the pavement resistance to asphalt concrete (AC) rutting, bottom-up fatigue cracking, and IRI. Both nanoclay- and nanosilica-modified asphalts extended the pavement life in most of the studied scenarios with one scenario achieving up to 9 and 13 years more life than the unmodified asphalt, respectively. [ABSTRACT FROM AUTHOR]