Perpetual Pavement Design Research Articles

Full-scale accelerated load testing of a new mechanised cement bound macadam (MCBM) pavement

The purpose of the research is to define and describe the performance behaviour during full-scale accelerated loading for a new heavy duty pavement type referred to as Mechanised Cement Bound Macadam (MCBM). MCBM is a cost-effective and reduced carbon footprint alternative to structural asphalt concrete and conventional concrete pavements. Four MCBM test sections were constructed with two key considerations in mind, the influence of layer thicknesses and maximum stone size within the gradation. In addition, defining the fundamental strength behaviour of the pavement, the failure mechanisms and their impact on perpetual pavement design were key objectives for the research. Dynamic and semi-static deflection measurements, strain measurements from strain gauges embedded in the pavement, crack mapping and transverse surface profile were collected at intervals throughout the accelerated loading. Performance testing showed that the stone interlocked structure is unique and undergoes multiple strength phases, enabling excellent shear and rut resistance by upholding vertical load bearing. The accelerated load testing also proved that significant structural strength remains post-bound phase. However, the MCBM design is based on a bound phase criterion and specifies a threshold fatigue stress value less than 30% of the flexural strength (breaking strength under four-point beam testing). Hence, the MCBM is perpetual by design and intended to function in the bound phase, requiring only intermittent resurfacing.

Optimizing perpetual pavement design in India: stabilized soil and polymer-modified bitumen approach for cost and carbon efficiency

Optimizing perpetual pavement design in India: stabilized soil and polymer-modified bitumen approach for cost and carbon efficiency

Analysis of performance of asphalt pavements in Qatar using mechanistic-empirical approaches

Qatar roads are experiencing heavy traffic loads due to the rapid increase in the country’s population and construction projects over the past two decades. Considering the demand for high-performing, sustainable, and cost-efficient pavements, emphasis has been placed on using different asphalt modifiers and recycled materials in pavement layers. These modifiers/recycled materials change asphalt mixture properties, and consequently, influence pavement performance. The main objective of this study is to evaluate the performance of pavement sections that incorporate various types of asphalt mixtures and are subjected to traffic levels that range from 5 to 200 million equivalent single axle loads (ESALs). The analysis of pavement performance was conducted via three methods: Australian pavement design method implemented in Circly software, perpetual pavement design using PerRoad software, and a simplified mechanistic-empirical pavement design method (MEPD) that utilizes performance models used in AASHTOWare. The outcome of these analyses was the selection of suitable combinations of asphalt mixtures as well as the optimization of pavement layer thicknesses for different traffic loads. The results highlighted that the use of a high-stiffness mixture incorporating modified asphalt (PG 82E-10) in the wearing course should be used with caution in high traffic load sections (≥100 million ESALs). These stiff layers could be susceptible to cracking when the underneath asphalt layers have much less stiffness (50–70% less stiffness). However, in the medium traffic level (10–50 million ESALs) sections, pavement performance improved by using a stiff mix incorporating a PG 82E-10 binder in the wearing course layer. In addition, the use of crumb rubber (CR) modified asphalt reduced the material cost of a pavement section relative to the use of polymer-modified binder. The results show that it is desirable to use French EME (Enrobés à Module Elevé) mix in the base course layer for heavy traffic roads as this mix help to reduce pavement layer thicknesses and overall material cost. The outcomes of the analysis showed that the rutting thresholds commonly used in MEPD method are too restrictive (low thresholds) for heavy-duty pavements in Qatar hot climate. It is recommended to increase the rutting thresholds for such pavements.

Asphalt fatigue endurance limit estimation and impact on perpetual pavement design

ABSTRACT The National Cooperative Highway Research Program (NCHRP) Project 9-38 developed a method for estimating asphalt fatigue endurance limit (FEL) which employs bending beam fatigue (BBF) lives. Another project, NCHRP 9-44A, used BBF test data to formulate a healing-based FEL prediction model. Both procedures were evaluated in this study by utilising data from the National Center for Asphalt Technology Pavement Test Track. The estimated FELs were used in perpetual pavement design to investigate their impact on asphalt thickness. The NCHRP 9-44A-predicted FELs increased with longer rest periods, but largely stabilised after 8 s, which agreed with the NCHRP 9-44A researchers’ conclusion that no healing occurs after a rest period of 5–10 s. Overall, the NCHRP 9-38 method yielded greater FELs. Without binder modification and/or high binder content, both methods provided similar FELs, if a rest period longer than 5 s was entered in the NCHRP 9-44A model. Generally, the NCHRP 9-44A-predicted FELs produced thicker layers. However, for conventional asphalt mixtures, both sets of FEL yielded similar thicknesses, if the NCHRP 9-44A model applied a rest period exceeding 5 s. The NCHRP 9-44A model’s predictive capability will increase if it is recalibrated with mixtures containing modified binder and/or higher binder contents.

Limiting Strain Distribution Criteria for Perpetual Pavement Design Using AASHTOWare Pavement ME Design

Perpetual asphalt pavement designs have been based on controlling horizontal strains at the bottom of the asphalt layer and vertical strains on top of the subgrade to prevent bottom-up fatigue cracking and subgrade rutting, respectively. Traditionally, single strain thresholds had been used as limits where damage accumulation begins and propagates. The concept of strain distributions was introduced at the National Center for Asphalt Technology (NCAT), and it was found to better represent the wide response spectrum in asphalt pavements caused by the different loading and environmental conditions. This concept was developed based on information and data collected from the NCAT Pavement Test Track, and from this a limiting strain distribution was created to assist with perpetual pavement design. Several studies analyzed the criteria using pavement responses calculated from PerRoad predicted strains in Test Track sections and existing perpetual pavements. A limitation of the AASHTOWare Pavement ME Design software is its inability to output the pavement responses necessary for perpetual pavement design. The objective of this study was to analyze pavement response data predicted from an integration of the AASHTOWare Pavement ME Design software outputs and a JULEA based program developed at NCAT to create a limiting strain distribution for perpetual pavement design using the AASHTOWare Pavement ME Design software. Strains were calculated for Test Track sections using these tools and based on the results a limiting strain distribution was developed. This limiting strain distribution was then further evaluated using eight sections that won Perpetual Pavement Awards. Results showed that the horizontal strain distributions obtained from Test Track sections could differentiate the sections with cracking and the sections that did not crack. In the further evaluation, the horizontal strain distributions from the perpetual pavements did not exceed the limiting strain distribution developed from the Test Track sections, except for a section which surpassed it by a small margin at the 80th and higher percentiles. Vertical strains were also determined for these pavements and the current 200 microstrains at 50th percentile design criteria was met by all the sections.

Are current design service lives for asphalt concrete pavements suboptimal? An analytic argument for longer design service lives

ABSTRACT One would expect the service life to be treated as an endogenous variable to be optimized in design procedures, but this is often not the case. This article provides a solution to the net-benefit maximizing choice of the design service life as a closed form equation. Using the 1993 AASHTO Design Equation, it is shown that for real discount rates under 4%, design service lives over 72 years are net-benefit maximizing given constant traffic loads. For lower discount rates, optimal service lives are considerably longer. This finding is consistent with perpetual pavement design as well as with optimal maintenance strategies involving multiple resurfacing cycles. Discounting is shown to be a key driver of the solution. Additionally, a simple method is shown on how to calculate an economically maximum pavement thickness that is independent of physical parameters. A methodology to simplify the AASHTO equation for use in analytic modelling is shown.

Accelerated Pavement Testing of Perpetual Pavement Test Sections under Heavy Aircraft Loading at FAA’s National Airport Pavement Test Facility

Abstract Six flexible pavements were constructed for construction cycle 7 (CC7) at the Federal Aviation Administration (FAA) National Airport Pavement Test Facility in Atlantic City, New Jersey. Four test sections on the north side measure 200 mm (LFP-4), 250 mm (LFP-3), 300 mm (LFP-2), and 375 mm (LFP-1) that are made of hot mix asphalt (HMA) over an aggregate subbase (thickness varying between 850 and 1,025 mm) resting on a subgrade with a California bearing ratio of 5.5. The fifth test section, LFC-5, is conventional flexible pavement with 125 mm of HMA over aggregate base and subbase, and the LFC-6 structure is the same as LFC-5 except that the crushed stone base layer is replaced with asphalt-stabilized drainable base. The objective of CC7 tests is to develop perpetual pavement design criterion and to validate or refine the fatigue model for HMA in airport pavement thickness design software FAARFIELD. The HMA fatigue model is based on the ratio of dissipated energy change (RDEC). Four fiber optic strain plates were installed to measure transverse and vertical strains at top and transverse strains at bottom within the HMA layer. Full-scale accelerated pavement tests were performed. Traffic test load parameters were six-wheel gear, 245-kN wheel load (gear load 1,470 kN), and 4-kmph speed. Pavement performance was monitored using crack maps, straight edge rut depth, and surface profile measurements. LFC-5 and LFP-4 showed significant fatigue cracks and rutting. LFP-1 and LFP-2 performed well with no signs of cracking. This article presents a discussion on the RDEC fatigue model, pavement thickness design, pavement material characterization test results, pavement instrumentation, accelerated pavement tests under heavy aircraft gear loads, and pavement responses measured using embedded sensors. The test section performance shows that, under loading conditions used in the study, by increasing HMA thickness from 25.4 to 30.5 cm, fatigue cracking was eliminated for the duration of testing (38,000 passes).

Forensic approach to predict film thickness of reacted and activated rubber (RARX) modified asphalt mixtures

The major objective of this study was to arrive at an optimum threshold asphalt binder film thickness, and develop predictive equation that includes materials and mixture properties, which could be used in all future forensic assessment of asphalt mixtures. Also, 18 field asphalt mixtures constructed as test sections were investigated for their field performance and correlated with . Furthermore, the performance criteria set by Arizona department of transportation (ADOT) in the USA to assess the field mixtures were related to established in this study. An optimum of 12 µ was selected as the threshold magnitude for asphalt mixtures that incorporates activated crumb rubber modified products, termed RARX. It was found that with increase in the overall cumulative surface area (SA) of the mix matrix, the required binder content also increased, in turn decreasing . predictive equation encompassing materials properties and associated volumetrics was established as a best-fit nonlinear regression model that had excellent statistical measures: R 2 = 99.8%; Se/Sy = 0.0447. It is noteworthy that the predictive model was established using the robust concept that introduced utilisation of SA of the whole mixture matrix, including, those that of SA of aggregate fractions not estimated by current models. Based on the methodical approach followed in this study to calculate , it is recommended that more amount of RARX be tried in other mixtures to enhance pavement performance. The current study involved only 18 field asphalt mixtures, amongst which six were without RARX. So, it is suggested that additional field sections be placed and monitored for their performance keeping in mind the volumetrics and specifically, , which can potentially be a quality control parametric assessor for field performance forensic evaluation, and that which becomes an integral characteristic in perpetual pavement design philosophy.

Mechanistic-Empirical design of perpetual pavement

Perpetual pavements use multiple, durable asphalt layers to produce a safe, smooth, long-lasting road. The pavement design begins with a strong, yet flexible bottom layer that resists tensile strain caused by traffic, and thus stops cracks from forming at the bottom of the pavement. Four perpetual pavement sections were designed and constructed in 2005 and currently are scheduled for rehabilitation for top-down surface cracking. These cracks have been confirmed by full-depth cores. This study revisited the design of these perpetual pavement sections using now available PerRoad and AASHTOWare Pavement ME Design software to investigate whether the design assumptions were correct. Fatigue lives of these sections were also evaluated based on bottom-up cracking. Layer moduli were backcalculated from the falling weight deflectometer (FWD) deflection data using the EVERCALC software. Tensile strains at the bottom of the asphalt layer were then computed. Results showed that predicted strain values derived from the mechanistic response models were lower than the tensile strains computed using moduli from the FWD deflection data. The required asphalt thickness from PerRoad was relatively higher than the asphalt thickness obtained from the AASHTOWare Pavement ME Design software over a 50-year design period. The study identified the most successful perpetual pavement design as the one with a rich bituminous mix in the base layer.

Development of a national database of asphalt material performance properties in support of perpetual pavement design implementation in Australia

There were concerns in the Australian industry that the current pavement design procedure was producing excessively conservative asphalt thicknesses. One of the barriers to producing a new design method is that there is limited data on the material characteristics of asphalt mixes. The Australian Asphalt Pavement Association (AAPA) initiated the Asphalt Pavement Solution for Life (APS-fL) project in 2010 to address this gap. This paper presents the outcomes of the first phase of the project in which a database of mechanical properties for 28 typical dense-graded Australian asphalt mixes was established, along with rheological properties of their binder constituents. Dynamic modulus tests were carried out on the asphalt mixes at various temperatures, loading frequencies, and confinement pressures. Virgin, Rolling Thin Film Oven aged (RTFO-aged), mastic and recovered binders were also tested for their rheological properties in the Dynamic Shear Rheometer. In this paper, the mechanical behaviour database on asphalt mixes has been presented in the form of sets of master curves and shift factors’ fitting parameters at all levels of confinement pressure. The binder rheological properties are expressed in terms of viscosity A-VTS charts as well as complex shear modulus and phase angle master curves and fitting parameters. The established database can be used in mix-specific pavement design approaches. It also facilitates implementation of the perpetual pavement design concept in Australia.

Effect of Pavement Structure on the Mechanical Response and Performance of Perpetual Pavements at the National Airport Pavement Test Facility

Construction Cycle 7 (CC7) conducted at the FAA National Airport Pavement Test Facility (NAPTF) was aimed to study the effect of hot mix asphalt (HMA) layer thickness and develop perpetual pavement design criterion for airfield flexible pavements. Four fully instrumented perpetual test pavements were designed, constructed, and tested, with all test items trafficked under heavy aircraft loads using a three duals in tandem configuration. Pavement condition was monitored using heavy weight deflectometer tests, distress surveys, and surface profiles. Comprehensive response data analysis revealed that increasing HMA layer thickness significantly reduced the tensile strain at the bottom of the HMA layer, permanent deformation in the unbound layer, and vertical stress at top of the subgrade. Thicker HMA test items exhibited better rutting performance, as evidenced in both multiple depth deflectometer and surface profile data. The interaction between HMA layer temperature and thickness was captured in the pressure cell responses. More tests are planned to determine the threshold HMA strain to prevent fatigue cracking.

Further Evaluation of Limiting Strain Criteria for Perpetual Asphalt Pavement Design

Perpetual asphalt pavements have been designed with single threshold values for the horizontal strains at the bottom of the asphalt concrete layer and for vertical strains on top of the subgrade to prevent the occurrence of bottom-up fatigue cracking and subgrade rutting. Several thresholds have been utilized for design based on laboratory and field test results. Limiting strain distributions were recently proposed for perpetual pavement design instead of single threshold values for controlling the horizontal and vertical strains. These design criteria were developed with data collected from test sections at the National Center for Asphalt Technology pavement test track. The objective of this study was to conduct additional analyses of eight perpetual pavement sections located in different climatic regions, to support the proposed limiting strain criteria. These sections were simulated in the PerRoad perpetual pavement design software to determine the horizontal strains at the bottom of the asphalt concrete layer and the vertical strains on top of the subgrade. The strains were then analyzed to evaluate the proposed limiting strain criteria. Based on the simulations, the limiting horizontal strain distribution above the 60th percentile can effectively differentiate the calculated strain distributions of the eight perpetual pavement sections from those of the test sections that failed due to bottom-up fatigue cracking on the test track. In addition, the calculated vertical strains on top of the subgrade at the 50th percentile were lower than the proposed 200-microstrain limit. These results provide additional support for utilizing the proposed strain criteria in perpetual asphalt pavement design.

Application of viscoelastic continuum damage approach to predict fatigue performance of Binzhou perpetual pavements

For this study, the Binzhou perpetual pavement test sections constructed in Shandong Province, China, were simulated for long-term fatigue performance using the layered viscoelastic pavement analysis for critical distresses (LVECD) finite element software package. In this framework, asphalt concrete was treated in the context of linear viscoelastic continuum damage theory. A recently developed unified fatigue failure criterion that defined the boundaries of the applicable region of the theory was also incorporated. The mechanistic modeling of the fatigue mechanisms was able to accommodate the complex temperature variations and loading conditions of the field pavements in a rigorous manner. All of the material models were conveniently characterized by dynamic modulus tests and direct tension cyclic fatigue tests in the laboratory using cylindrical specimens. By comparing the obtained damage characteristic curves and failure criteria, it is found that mixtures with small aggregate particle sizes, a dense gradation, and modified asphalt binder tended to exhibit the best fatigue resistance at the material level. The 15-year finite element structural simulation results for all the test sections indicate that fatigue performance has a strong dependence on the thickness of the asphalt pavements. Based on the predicted location and severity of the fatigue damage, it is recommended that Sections 1 and 3 of the Binzhou test sections be employed for perpetual pavement design.

Impact of asphalt concrete fatigue endurance limit definition on pavement performance prediction

Many well-constructed Hot Mix Asphalt pavements have been in service for 40 or more years without any evidence of fatigue cracking. This field experience suggests that there exists a strain level, known as the fatigue endurance limit (FEL), below which an asphalt concrete pavement will not exhibit fatigue cracks. Several studies have been conducted to define and verify this limit. Each of these methods is associated with certain assumptions regarding the nature of the FEL and heretofore a comprehensive comparison of each has not been made using a consistent set of mixtures. Likewise, the impact of any observed differences in FEL on the predicted pavement performance has not been made. This paper investigates and compares six different methods for identifying the FEL: NCHRP 9–44A approach, simplified viscoelastic continuum damage model, smeared-healing with continuum damage model, plateau value approach, pseudo-strain analysis method, and reduced cycles method. Each method is found to yield different values ranges from approximately 30–170 microstrains at 21.1 °C. The predicted FEL from each of the six methods are then used with the mechanistic empirical design algorithm to evaluate their effects on predicted pavement performance. Simulation outputs show different pavement performance and perpetual pavement structural design thicknesses from each of the methods. The study outcomes are expected to benefit future field verification research of FEL as it provides comprehensive analyses using six different methods. This future verification research may indicate the method that best represents actual perpetual pavement design and performance.

Adaptation and validation of stochastic limiting strain distribution and fatigue ratio concepts for perpetual pavement design

Traditional perpetual pavement thickness design is based, in part, on controlling strain levels at the bottom of the asphalt concrete layer below an endurance limit to prevent bottom-up fatigue cracking (FC). A field-based limiting strain threshold was developed from cumulative distributions of field-measured tensile strains in the 2003 and 2006 research cycles at the National Center for Asphalt Technology Pavement Test Track to understand the limiting strain necessary to control FC. Additionally, the fatigue ratio, the ratio of the nth percentile strain to the fatigue endurance limit, was developed. Both the tensile strain distributions and fatigue ratios showed a clear difference between sections that experienced bottom-up FC and those that did not. However, it is necessary to adapt these thresholds to strains predicted by perpetual pavement design tools. PerRoad, a stochastic perpetual pavement design programme, was used to predict strains for the same 2006 sections. Previously developed strain distributions and fatigue ratios were adjusted to reflect observed differences in predicted and measured strains. Cumulative distributions and fatigue ratios based on predicted strains for the 2009 research cycle validated the updated limiting strain distribution and maximum fatigue ratios for designing perpetual pavements to resist bottom-up FC.

Impact of Freeze–Thaw Cycles on Mechanical Properties of Asphalt Mixes

This study presented a statistical assessment of the impact of freeze–thaw cycles on deterioration of the mechanistic properties of asphalt mixes. The experimental matrix included several samples of asphalt mixes that were tested with dynamic modulus. The specimens were retested after being subjected to freeze–thaw cycles to simulate the impacts of the Canadian climate on asphalt mixes. The Ministry of Transportation of Ontario constructed a test section in partnership with the University of Waterloo, the Ontario Hot Mix Producers Association, the Natural Sciences and Engineering Research Council of Canada, and other partners to evaluate the use of perpetual flexible pavement design in southern Ontario, Canada. The test section was constructed on Highway 401, and samples from several asphalt mixes used in construction were structurally evaluated through dynamic modulus testing shortly after construction. The samples were then subjected to freeze–thaw cycles and retested to evaluate the environmental impact on dynamic modulus (| E*|) as a representative of pavement structural deterioration. The dynamic modulus results were used to evaluate the benefits obtained by adding 0.8% of additional binder to the regular Superpave® (SP) 25 mix to develop an SP 25 rich bottom mix (RBM). The dynamic modulus results did not show a statistically significant difference between the average | E*| of the SP 25 and SP 25 RBM after construction. However, the benefits of additional binder content showed up clearly after freeze–thaw cycles simulating 1 year in service. Overall, the study provided guidance on perpetual pavement design and the various asphalt layer performances within the design.

Fiber/Polymeric Compound for High Modulus Polymer Modified Asphalt (PMA)

The road construction sector has made a big research effort in recent decades, mostly aimed at better understanding the behaviour of the asphalt mixes contained in most such pavements. Hence the introduction of new binders, all based on bitumen as in the past but featuring polymers and reinforcements of various nature as well as innovative pavements. Moreover, newer regulations allow better predicting the behaviour of materials and their mixtures once laid, thanks to more rational testing methods. However both asphalt binder and asphalt-aggregate mixture show temperature and time-dependent behaviour. Rutting or permanent deformation is therefore the leading cause of pavement deterioration in temperate and warm climatic regions of the world while low-temperature cracking is a common problem in cold regions.The paper illustrates that the proposed innovative fiber/polymer compound may be potentially considered from now on as a relevant solution for sustainable long life pavements that do not deteriorate structurally, needing only timely surface maintenance and allowing reduced base course thickness (due to enhanced stiffness and fatigue properties) lead to a cost- effective and eco-friendly perpetual pavement design. Polymer Modified Asphalt (PMA) are modified asphalt concrete manufactured by feeding the fiber and/or the polymeric compound into the asphalt plant mixer after the aggregate has been loaded in to the mixer immediately before the bitumen is added. Fiber/polymeric compound asphalts may be preferable technology whenever a pavement is required to perform structural resistance, stiffness and resistance to rutting. One such application could be the manufacturing of ‘high-modulus’ mixes (EME), for laying heavy-duty base courses. These mixes are characterized by great coarse aggregate cohesion and high physical and chemical modified grade bitumens to obtain the EME2 specifications requirements, in particular high stiffness modulus value at 15°C and high fatigue resistance, allowing for reduced pavement thickness and greater longevity.Fiber/Polymer modified Hot Mix Asphalt (PMA) has been claimed to resist rutting since they are less susceptible to reduction of the asphalt cement viscosity with high pavement temperatures during the summer months while the fiber component increase the resistance to tensile stresses and consequent cracking. Laboratory assessment of such materials consisted in the evaluation of the mix compactability, moisture resistance, rutting resistance at 60°C, stiffness modulus at 15°C and 35°C and fatigue resistance at 10°C.

Response of Perpetual Pavement under Different Axle Heavy Truck

To investigate suitability of the perpetual pavement under ultra-heavy loads, a test road was constructed on expressway in Shandong province of China. There were five pavement structures include semi-rigid asphalt pavement, each was instrumented with gages for measuring the strains of asphalt base layer, the vertical stress of subgrade, temperature of asphalt layers. The analysis of the strain data indicated that the strain values are affected by the temperature, the vehicle load, axle type, and the pavement structure combination. To research the response of different structure, tested different axle and load at different temperature, then different pavement response models were developed that accounts for layer thickness, axles load, pavement temperature and equivalent modulus of pavement foundation. The models provides good references under heavy vehicle loading and China local climate, it will be useful for perpetual pavement design.

Implementation of mechanistic-empirical pavement analysis in the State of Qatar

The State of Qatar is experiencing tremendous growth in infrastructure including road network and highways. The current methods used in design of asphalt pavements in the State of Qatar are empirical and might not be suitable for the design of long-lasting pavements. Given the significant increase in traffic, road authorities in the State of Qatar have been considering the use of mechanistic-empirical methods in the design and analysis of asphalt pavements. This study documents the results of a study in which the mechanistic-empirical pavement design guide (M-E PDG) software was used in the design of asphalt pavements with input parameters that were carefully selected to reresent local materials and climatic conditions. The selection of material properties was based primarily on specifications and design guides in the State of Qatar and on published literature about these materials. The mechanistic-empirical method was also used to assess the benefits of adopting the concepts of perpetual pavement design and also to compare the performance of pavement structures in which various bitumen grades, granular bases and chemically stabilised sub-base were used. A life-cycle cost analysis was carried out to determine the design with the highest net present value among the various options investigated. It is expected that the outcomes of this study would promote the use of mechanistic-empirical methods in the State of Qatar and the region. Inevitably, this will require significant efforts to calibrate material and damage prediction models used in the M-E PDG for more accurate representation of material properties and measured pavements performance.

Sustainability of Perpetual Pavement Designs: Canadian Perspective

Sustainability of road construction is one of the key factors affecting the global environment, economy, and future social development. Several research projects are currently under way to study different construction approaches, materials, and designs that can improve the sustainability of roads. Although perpetual pavement is characterized by higher construction costs compared with conventional flexible pavement designs, it requires less maintenance and less frequent rehabilitation if designed and constructed properly. Pavement design can conserve materials and energy used for maintenance over the pavement life cycle and reduce the noise and emissions that accompany maintenance activities. Highways are typically subjected to heavy truck loads, which results in rapid structural deterioration. Because of the importance of highway conditions, the structural capacity of highway pavements should be maintained to the highest standards to ensure safety and a high level of service. Perpetual pavement designs are capable of achieving high structural capacity and can resist deterioration with minimum surface treatment. The case study presented examines how perpetual pavement design is a feasible solution for sustainable roads. The construction of a test section on Highway 401 in Woodstock, Ontario, Canada, is explained and analyzed. Three sections, representing conventional pavement design, perpetual design without rich bottom mix, and perpetual design with rich bottom mix, were constructed next to each other for a comparison of their performance with different sensors. Recycled asphalt pavement was used in all pavement layers in this project. The use of recycled materials enhanced the pavement mechanical characteristics and maximized the efficient use of resources.