Conventional Flexible Pavements Research Articles

Comparative Study of Mechanistic-empirical Structural Design Methods Applied to Sustainable Asphalt Mixtures

Introduction/ Background Nowadays, there is a growing interest in achieving sustainable alternatives to conventional flexible pavements. The incorporation of recycled materials into asphalt mixtures has become a departure point. This study focuses on developing sustainable asphalt mixtures incorporating different residues to find a material that performs well on both technical and environmental grounds. Materials and Methods Mixtures with recycled materials and others are compared on a pavement structure. A mechanistic-empirical pavement design method is used to carry out analyses in different conditions. A Life Cycle Assessment is conducted to consider the balance of positive and negative environmental aspects of each mixture and pavement structure. Results The results indicate that all mixtures with sustainable features have a longer life span and an enhanced performance. They also incur higher impacts per tonne produced. However, the “avoided impact” is considered in their favour. Discussion Mixtures with enhanced mechanical properties are key to achieving long-term environmental benefits. The usage of local materials is also essential. Conclusion Proving that unconventional mixtures have a satisfactory performance requires innovative, properly calibrated models and a thorough material characterization. Accurately reflecting on their in-service behaviour is key to evaluating the environmental benefits.

Enhancing California Bearing Ratio through Optimized Compaction Efforts: A Study on Alluvial Soils in North India

The quantity of soil required for embankment construction is enormous. Often the soil is brought to the site in dumpers in multiple rounds. This to and from movement of the wagons leads to the deterioration of the existing flexible pavement. In the absence of good earth nearby, using existing soils to act as a subgrade material upon meeting the desired strength and stability characteristics is the need of the hour. The California Bearing Ratio (CBR) is an indicator of soil's strength, which further depends on the degree of compaction of soil. In this study, an effort has been made to find the required compaction efforts to achieve maximum CBR value finding its applicability for both conventional flexible and perpetual pavements. Three different types of alluvial soils in North India were tested for CBR with varying compaction efforts using the modified Proctor test. The effect of mixing different soils was also considered to find the effectiveness of mechanically mixing soils on the required compaction efforts. It was observed that there is a constant upsurge in the CBR of soils upon an increase in the percentage compactive effort up to a certain limit. In the case of clayey soils, the rate of increase is less as compared to the well-graded sands. This study also highlights the effect of mechanical mixing of such soils with sandy soils in desired proportions giving rise to amplified values of CBR ratio of the soil blend. The regression analysis was also conducted to examine a correlation between the compactive effort and CBR values and it was best represented by exponential function for different types of soils.

RUTTING PERFORMANCE OF TREATED LOW-DENSITY POLYETHYLENE AS ADDITIVE ON THE SUSTAINABLE MIXTURE

Rutting is a major distress issue in conventional flexible pavements causing the service life of road pavement reduced. A lot of efforts had been carried out to modify the hot mix asphalt mixture to overcome the problems. However, asphalt modification mainly increased the initial cost of road construction, which had forced many road agencies and researchers to use waste materials as modifiers. In this study, the potential use of low-density polyethylene powder made by waste plastic bag (treated) as an additive on the performance of rutting resistance was investigated by Marshall, resilient modulus, dynamic creep and double wheel tracker tests. The results showed that 0.75% of treated plastic (TP) by weight of total aggregate attained higher performance in rutting resistance than the conventional mixture. It can be concluded that the waste material additive not only increases the mixture performance but more towards mixture sustainability.

Preliminary optimization design of inverted asphalt pavement structure using response surface method

Inverted asphalt pavement (IAP) has the advantage of maintaining good performance under the condition of thin asphalt concrete (AC) layer compared with conventional flexible asphalt pavement. The stress-dependent property of unbound aggregate base (UAB) plays an important role in mechanistic responses of IAP. The focus of this paper is to quantitatively analyze the function of UAB’s stress-dependent property on the structure combinations design of IAP using response surface method (RSM). In this paper, an improved UMAT subroutine was developed to characterize the stress-dependent stiffness of UAB. The three-dimensional FE pavement model was established and validated against KENLAYER calculation and field FWD test deflection data. The critical mechanical response, maximum principal strain and bulk stress, were selected to evaluate the fatigue performance of AC layer and stress-dependent property of UAB. The significance analysis was conducted to describe the relationship between input variables (thickness and stiffness of structural layers) and the critical mechanical response variables. An optimization design method to balance the fatigue performance and stress-dependent property was proposed to obtain the optimal structure combinations of IAP. Research results demonstrate that the thickness and stiffness of the AC and UAB layers present a clearly significant impact on the maximum principal strain at the bottom of AC layer and the bulk stress in UAB, particularly during the summer season, whereas the thickness and stiffness of CTB and stiffness of subgrade have a minor impact. The responses of bulk stress and maximum principal strain can be empirically predicted by 2FI and Quadratic models. Optimal structure combinations (13.6 cm AC layer and 10 cm UAB) were recommended after quantifying the stress-dependent properties of UAB. The recommended structural combination has good fatigue resistance and can also efficiently minimize AC and UAB layer thickness.

Environmental and economic feasibility of implementing perpetual pavements (PPs) against conventional pavements: A case study of Barranquilla city, Colombia

The road infrastructure industry consumes elevated economic resources and generates vast environmental impacts on the planet. Nevertheless, the construction and maintenance of pavements are necessary to guarantee the economic growth of the communities. In this way, finding novel methods, materials, and techniques is essential to achieve a more sustainable industry. One of the most promising alternatives is the implementation of Perpetual Pavements (PPs). Contrary to the Conventional Flexible Pavements (CFPs) and Conventional Rigid Pavements (CRPs), the PPs are designed for a long service life (even superior to 50 years). During this time, the PPs do not require major Maintenance and Rehabilitation (M&R) activities. Due to this characteristic, PPs could present greater sustainability attributes than conventional pavement structures. However, minimal literature is focused on examining these hypotheses since the state-of-the-art has concentrated on studying the mechanical behavior of materials and layers for PPs laying. Moreover, it is most worrying that few investigations have done this in the context of developing countries, where it is more decisive to perform better decisions in terms of economic-environmental sustainability. Consequently, this research conducts a case study on Barranquilla city (Colombia) to estimate the environmental burdens and monetary costs associated with the life cycle of three pavement alternatives, i.e., a PP, a CFP, and a CRP. The Life Cycle Assessment (LCA) and Life Cycle Cost Analysis (LCCA) methodologies were employed for these purposes. The results of this investigation demonstrated that PP provides less environmental damage and higher cost-efficiency than the CFP and CRP alternatives. Notably, the most significant contamination potential is provoked by the CRP structure. Meanwhile, the fewer financial profitability is caused by the CFP structure. Therefore, this study indicates that under the typical circumstances of underdeveloped nations, PPs are a more advantageous alternative than traditional ones regarding sustainability performance.

Parametric analysis of the minimum cost design of flexible pavements

This paper presents recommendations for an optimal pavement design. For this purpose, eight optimization models were developed, each corresponding to a different type of pavement. The optimization models were used to obtain the optimal designs for different design data. These results were used to perform a multi-parametric analysis, from which the design recommendations for an optimal design were derived. Since the optimization was performed for a large number of design-parameter combinations, the manual execution of the optimization algorithm was not feasible. Therefore, the optimization model was developed to include a loop to perform an optimization for each of the combinations. This study discusses the project data in which geosynthetically reinforced flexible pavements outperform conventional flexible pavements. In addition, the results of the study allow a direct comparison between geosynthetic reinforced and unreinforced flexible pavement structures once they are optimized.

Fatigue Prediction Model and Stiffness Modulus for Semi-Flexible Pavement Surfacing Using Irradiated Waste Polyethylene Terephthalate-Based Cement Grouts

Semi-flexible pavement surfacing, or grouted macadam, is an alternative to conventional flexible and rigid pavement. It is constructed by injecting cementitious grout into the voids of an open-graded asphalt surfacing. The cement used in cementitious grouts has adverse environmental effects because of the carbon dioxide emission in cement production. The objective of this study was to investigate the potential of using irradiated waste polyethylene terephthalate (PET) and fly ash (FA) as a (partial) cement replacement in cementitious grouts for semi-flexible pavement surfacing. This study sought to assess the stiffness modulus and fatigue properties of the semi-flexible specimens prepared with control grout, regular PET (2.57% PET + 10% FA) and irradiated PET (4.75% PET + 10% FA)-based grouts and compares the stiffness modulus and fatigue properties of semi-flexible specimens with the conventional hot mix asphalt (HMA) concrete. The semi-flexible surfacing specimens showed superior performance, higher stiffness modulus, and better fatigue life than the hot mix asphalt. The difference in fatigue cycles was apparent at lower stress ratios of 25 and 30%. The semi-flexible pavement mixtures exceeded 100,000 cycles at the lowest stress ratio of 25%, while the HMA fatigue cycles were less than 100,000 cycles. Furthermore, the semi-flexible specimen with irradiated PET (which contain a higher amount of waste PET than the regular PET) showed similar stiffness modulus and fatigue life as the specimens with regular PET and control grout. The irradiation technique offers a sustainable solution for recycling higher amounts of waste PET in highway materials for semi-flexible pavement surfacing.

Application of Graphene-Based Nanomaterials as a Reinforcement to Concrete Pavements

Nanomaterials are considered to be one of the game-changing features in the modern world and nanotechnology is mostly reputed as the next-generation industrial revolution due to the extraordinary characteristics possessed by them at their very small scale. Graphene and graphene oxide are two main nanoscale materials that have seen a drastic increase in their use in cement-based composites due to exemptional enhancements in terms of strength and durability that can be imparted to compromise the inherent flaws of concrete and other cementitious composites. The main aim of this study was to investigate the effect of graphene and graphene oxide on improving the performance of cement-based composites and, particularly, of continuously reinforced concrete pavements (CRCP), which is one of the emerging trends in the transport sector due to various advantages they bring in over conventional flexible pavements and unreinforced concrete pavements. Fresh, hardened and durability properties of concrete with graphene-based nanomaterials were studied and the past experimental data were used to predict statistical interferences between different parameters attributed to concrete. According to the review, graphene-based nanomaterials seem to be promising to overcome the various CRCP distresses. Simultaneously, the possibilities and hinderances of using graphene and graphene oxide in cement-based composites as a reinforcement are discussed. Finally, the potential of using graphene in continuously reinforced concrete pavements is explored.

Evaluating the performance of inverted pavement structure using the accelerated pavement test (APT)

• Full-scale inverted pavement was investigated. • Accelerated pavement test was applied to the inverted pavement. • Rutting performance between inverted and conventional pavements was compared. • Inverted pavement structure outperformed the conventional flexible pavement. Inverted pavement is considered an unconventional type of flexible pavement structure. In this pavement structure, an unbound aggregate base (UAB) with a low initial modulus is sandwiched (layered) between two stiffer layers, a thinner asphalt concrete layer (AC) and a cement-treated base layer (CTB). This paper presents a comparison study of the rutting performance (permanent deformation) between conventional and inverted pavement structures. In addition, the inverted pavements with different thicknesses of UAB and CTB were studied. The accelerated pavement test (APT) method was conducted on a full-scale pavement consisting of two inverted pavement lanes and one typical three-layer conventional flexible pavement lane as the control section for performance comparison. Significant permanent deformation was observed in all three pavement lanes after the completion of 100,000 passes of APT. Comparisons of the measured total deformations showed that the inverted pavement structure outperformed the conventional pavement. Furthermore, the inverted pavement with a thicker CTB layer exhibited less deformation compared with the inverted pavement with a thicker UAB layer. The stiffness of the UAB layer of the inverted pavement increased with the loading passes. A stiffer UAB could provide a cushion for the thin AC layer, resulting in less deformation in the AC surface compared with that of the conventional pavement. Furthermore, the loading on the pavement surface had a larger affected area in the inverted pavement structure. Based on the overall pavement conditions, the inverted pavement can be regarded as a promising alternative to the conventional flexible pavement, and the asphalt mixture layer thickness can be reduced during the construction.

Comparative Environmental Assessment of Rigid, Flexible, and Perpetual Pavements: A Case Study of Texas

Unlike conventional pavements with a service life of 20~30 years, perpetual pavements (PPs) are designed to have a 50-year service life without requiring major maintenance and rehabilitation (M&R) activities. In this way, PPs are more cost-effective than conventional rigid pavements (CRPs) and conventional flexible pavements (CFPs). Nonetheless, even though the economic and mechanical aspects of PPs have been widely studied and well documented, the literature is limited regarding the environmental assessment of PPs. Consequently, this research estimated the environmental burden associated with five pavement structures (one CRP, one CFP, and three PP structures) through the life-cycle assessment (LCA) methodology. Notably, the PaLATE computational tool was used to carry out the LCAs. The results indicated that for CFP, most of the environmental impacts are generated by the M&R activities. Otherwise, for CRP and PP structures, the most impact occurred during the initial construction stage. The study results also revealed that materials production is the sub-stage that most contributed to the generation of environmental detriments. Overall, this comparative case study concluded that the pavement alternative with the slightest environmental damage is the PP structure.

Cementitious Grouts for Semi-Flexible Pavement Surfaces-A Review.

The hybrid type of pavement called semi-flexible or grouted macadam has gained popularity over the last few decades in various countries, as it provides significant advantages over both rigid and conventional flexible pavements. The semi-flexible pavement surface consists of an open-graded asphalt mixture with high percentage voids into which flowable cementitious slurry is allowed to penetrate due to gravitational effect. Several researchers have conducted laboratory, as well as field, experiments on evaluating the performance of semi-flexible layers using different compositions of cementitious grouts. The composition of grouts (i.e., water/cement ratio, superplasticizer, polymers, admixtures, and other supplementary materials) has a significant effect on the performance of grouts and semi-flexible mixtures. A comprehensive review of cementitious grouts and their effect on the performance of semi-flexible layers are presented and summarized in this review study. The effect of byproducts and other admixtures/additives on the mechanical properties of grouts are also discussed. Finally, recommendations on the composition of cementitious grouts have been suggested.

A Review on the Use of Waste Material in Flexible Pavement

The day by day increase in the traffic in the country like India has to lead to a need for very good quality pavement, one of the most widely used pavements in India is flexible pavement but the conventional flexible pavement used has some problems in it such as rutting, potholes, etc. on the other hand waste disposal is also a problem in India waste such as plastic, coconut, coconut fibre, etc. these are some of the most common waste found in India. To deal with both the problems, the use of this waste in bituminous mix construction will improve the quality of pavement and also solves the problem of the disposal of this waste. This paper gives a review on the use of materials like coconut fibre, shell, and plastic waste in flexible pavement and also suggests some waste materials to incorporate into the mix.

Effect of dual and new generation wide-base tire assembly on inverted pavements

The conventional flexible pavements have been constructed such that the stiffness of the layer reduces with depth. The crust thickness becomes significantly high for heavy traffic corridors resulting in the consumption of large quantities of construction materials and also increasing environmental pollution. Inverted pavements with the aggregate interlayer (AIL) or stress absorbing membrane interlayer (SAMI) are considered to be one of the alternatives for thick conventional flexible pavements for heavy traffic corridors. The AIL or SAMI is placed between a stiff cement-treated base and asphalt concrete layer to function as crack relief layers. This change in the composition alters the behaviour of inverted pavements compared to the conventional flexible pavements. On the other hand, wide-base tires are being increasingly preferred by trucking industries due to increased fuel economy and cargo capacity. However, the effect of wide-base tires on the performance of inverted pavements is yet to be investigated. In this study, the 3D finite element (FE) models of inverted pavements considering different crack relief layers were developed, and load from dual-wheel and wide-base tires were applied. The stress-strain evolution in the various layers of inverted pavements was investigated and discussed in this study. The results indicated the higher stress and strains due to wide base tires compared to the dual-wheel assembly. Further, pavement with SAMI was found to result in lower stress and strains in the asphalt concrete layer compared to AIL pavements. • Pavement with stress absorbing membrane interlayer resulted in lower stress in asphalt layer. • Transition from compressive to tensile stress occurred at a depth of 0.66 times asphalt thickness. • Wide-base tires caused higher longitudinal stress in asphalt layer. • Confining effect of wheels due to low aspect ratio was observed for thin asphalt layers.

Effects of Modifiers on the Properties of Asphalt for Sustainable and Improved construction of Flexible Pavements

The need to modify the conventional type flexible pavement came up because of the rising advancement in the commercial heavy vehicles and day by day increasing vehicle density in the roads. This has led to increase in frequent monitoring and regular maintenance work of the flexible pavements. Present paper primarily focuses on two aspects, firstly to increase the life expectancy of the roads and second to build flexible pavement roads sustainably. The use of various modifiers such as plastic, glass, rubber, waste oil and fly ash in conventional pavements were studied and found to provide a way to reduce the use of asphalt and get desired strength of the pavement as per the design requirements in the present study.

Evaluation of the use of a HiMA binder to extend the durability of porous friction courses (PFC)

ABSTRACT Porous friction courses (PFC) are thin layers of asphalt mixtures with open gradations and high air void contents, which are placed over conventional flexible pavements. Although they improve various safety and environmental issues, their main difficulty is their short service life. A common practice to enhance PFC durability is the use of modified asphalt binders (e.g. regular polymer-modified asphalt (PMA) or asphalt rubber). However, this approach has not been enough to achieve life-spans close or equal to those of dense-graded hot mix asphalt. The use of highly polymer-modified asphalts (HiMA), which are binders modified at polymer doses near 7–8% by total weight of the binder, constitutes an alternative to overcome this challenge. This work evaluates the mechanical performance of four PFC mixtures fabricated with a regular polymer modified (PMA) and a HiMA binder, and two aggregate sources. The experimental plan included the semicircular bending (SCB), IDEAL-CT, Cantabro abrasion loss and Tensile Strength Ratio (TSR) tests at intermediate temperatures and various ageing conditions. Results indicate an enhanced cracking and degradation resistance for PFC mixtures containing HiMA and suggest that the use of this type of asphalt binder could increase the service life of these mixtures.

Evaluation of inverted pavement by structural condition indicators from falling weight deflectometer

Inverted pavement has been a potential alternative to the conventional flexible pavement structure due to its cost-efficient usage of asphalt, comparable performance and durability. For increasing utilization of the inverted pavements, appropriate structural evaluation is necessary. The Falling Weight Deflectometer (FWD) test has been widely accepted for evaluating the structural condition of conventional pavements through pavement deflection basin parameters (DBPs). As a special type of pavement, inverted pavement relies on the stress-dependence of the unbound stone interlayer to withstand the heavy traffic loads, which typically affects a relatively larger pavement area. So far, there have been few systematic studies on the effectiveness of utilizing FWD to evaluate the structural conditions of inverted pavements. This study used a DBPs-based inverted pavement structure assessment system to assess an inverted pavement constructed in Georgia, USA. A nonlinear stress-dependent finite element model of the inverted pavement coupled with the impulse loading mode was built to simulate the realistic FWD loading process and investigate the effect of layer stiffness on the DBPs evaluation system. Furthermore, a full-scale inverted pavement section in Knoxville, TN, USA, was tested by the FWD method to obtain the corresponding deflection basin parameters. The DBPs data were used to evaluate this practical inverted pavement project based on the aforementioned DBPs-based assessment system. The analysis results show that the DBPs-based pavement evaluation method can provide a quick and comprehensive assessment for each layer in the inverted pavement structure without knowing the detailed properties of the layers. The evaluation results were consistent with the data from the testing vehicle equipped with the laser crack measurement system. Thus, the DBPs-based evaluation system is a promising method to assess the condition of the inverted pavement structures, contributing to the Inverted Pavement Management System (IPMS).

An investigation of structural responses of inverted pavements by numerical approaches considering nonlinear stress-dependent properties of unbound aggregate layer

Inverted pavement has a unique structure that consists of an unbound aggregate base (UAB) layer sandwiched between a thin bituminous surface and a stiff cement-treated base (CTB). The stiffness of the successive pavement layers decreases with the depth, which is different from the conventional flexible pavement. The nonlinear stress-dependent property of the UAB layer plays a critical role in the structural response of the inverted pavement, which contributes to its service performance and durability. This paper presents simulations of 3-D finite element models verified by GTPAVE data to investigate the effect of the UAB layer on the pavement structures. The linear elastic and nonlinear elastic models were applied to both inverted and conventional pavements. The results show that the inverted pavement was more sensitive to the nonlinear stress-dependent property of the UAB layer due to the compaction effect from two stiffer layers of an upper thin AC layer and a lower CTB layer. The stress distribution along the load centerline, deflection along the asphalt concrete (AC) layer, and the stiffness distribution contours within the UAB layer were also investigated to make a comparison of the structural response between the inverted pavements and conventional pavements under the effect of the UAB layer. The comparison study presents that the inverted pavement had better performance and saved more asphalt under the same loading condition: (1) the bottom of the AC layer in the inverted pavement experienced lower tension; (2) the deflection along the AC surface was also much smaller than that of the conventional pavement. In addition, the inverted pavements with different thickness of the UAB layers were compared, which showed that a thicker UAB layer could increase the tensile stress at the bottom of the AC layer but relieve the tension transferred from the bottom of the CTB layer.

A system dynamics framework for mechanistic analysis of flexible pavement systems under moisture variations

The infiltration of water in pavement layers due to heavy precipitation, snow melting, surface water flow, or ground water fluctuation can lead to a substantial change in pavement performance under traffic loading. The extent of this change depends on several complex and interdependent factors such as climatic and mechanical stressors, hydro-geological material properties, and traffic loads. Due to a very large number of variables and their interdependencies, a system dynamics approach can holistically capture all significant variables and provide a tool to study and visualize governing factors and their effects on pavement response under variable initial and boundary conditions. The objective of this study is to develop and program a system dynamics model (SDM) to study the performance of pavement systems under extreme moisture variations in real time. The application of the model is illustrated by evaluating surface deflection of a conventional flexible pavement system with hypothetical material and precipitation conditions. A parametric study was also conducted to illustrate the capability of the proposed SDM to simulate moisture movement in subsurface and estimate pavement performance at variable initial conditions in real time. Results demonstrated that the pavements weakened through water infiltration may suffer a considerably high surface deflection. This indicated that the proposed SDM can be potentially used for load restriction decision making which results in provision of safe traffic passage as well as preservation of pavements’ structure during extreme climatic events.

Numerical study using stiffness parameters on the nonlinear behavior of RCA pavements under heavy traffic loads

The use of the recycled concrete aggregates (RCA) obtained from construction and demolition wastes not only reduces the demand for natural aggregate, which ultimately leads to economical and eco-friendly designs, but also improves the long-term performance of a conventional flexible pavement. This study aims to investigate the effects of using 100% RCA in the pavement subbase and base courses on the mechanical behavior of the flexible pavement. This study is divided into two stages, i.e., a laboratory study characterizing the properties of RCA and a numerical analysis evaluating the long-term performance of RCA under heavy traffic load conditions. In the laboratory study, along with the determination of the classical geotechnical properties of base and subbase samples, the stiffness properties of the samples were obtained by applying the resilient modulus test (RMT) and permanent deformation test (PDT). Then, by comparing the results of the three different constitutive models, the result of the more appropriate model was selected. In the second stage, the plastic deformation (rutting) of the pavement courses and the maximum value of deflection when subjected to multiple wheel loads were determined using a 3D nonlinear numerical method. Based on the experimental results, RCA demonstrated higher resilient modulus and lower plastic deformation compared to that of conventional base and subbase materials. Regarding the long-term behavior, the permanent strain rate of the samples was reduced at an approximately constant level during the first load cycles. Additionally, the numerical analysis results indicated that the mechanical performance and rutting values of the base and subbase courses constructed using 100% RCA met the specified requirements.

C-FLEX Advanced Finite Element Analysis Program for Flexible Pavement Analysis and Design

The U.S. Army Engineer Research and Development Center (ERDC) of the U.S. Army Corps of Engineers has initiated an effort to modernize the Department of Defense (DOD) pavement design and evaluation procedures initially developed in the 1950s. Flexible pavement analyses and evaluations are currently performed based on the elastic layered WESLEA and WESDEF software programs. To modernize the current pavement design and evaluation procedures used by the DOD, an advanced axisymmetric Finite Element Method (FEM) based analysis program, named C-FLEX, was developed and is introduced in this paper. The C-FLEX program is designed to feature accurate material models for all pavement layers with the capability to model the cross-anisotropic and nonlinear elastic properties of unbound base/subbase and subgrade layers, the viscoelastic behavior of the asphalt mixture, as well as mechanical reinforcement using geosynthetics in flexible pavements. The FEM formulation in C-FLEX and the program architecture and implementation details are introduced and discussed in this paper. The different analysis schemes and proper models used to characterize the cross-anisotropy and stress-dependent material nonlinearity are also described in detail. The viscoelastic analysis scheme and the geosynthetic characterization are currently under development and so are not included in this paper. Furthermore, two conventional flexible pavements with different layer properties are analyzed to verify the solutions and reliability of the C-FLEX program. Based on this development effort with ERDC, the C-FLEX program is envisioned to eventually serve as the flexible pavement analysis engine for the DOD’s new mechanistic design and evaluation platform.