Pavement Analysis Research Articles

Evaluating the Rutting Potential of Asphalt Mixtures with Simple and Practical Tests

The objective of this study was to explore the use of monotonic loading tests (“monotonic tests”) as screening tools to assess the rutting potential of dense-graded asphalt surface mixtures in Virginia. To that end, three monotonic tests—the indirect tensile at high temperature (IDT-HT) test, the rapid rutting (RR) test, and the Marshall stability and flow (MS) test—identified from the literature, were evaluated using 16 plant-produced asphalt mixtures with “A” and “D” designations. The scope of the work also included performing the multiple stress creep and recovery test on the extracted and recovered binders. The results were applied to assess the monotonic tests and the asphalt pavement analyzer (APA) test relative to each other using several performance metrics. The results were also employed to develop performance threshold criteria for the tests being considered. The results showed that the IDT-HT and RR tests can be used to screen the rutting potential of asphalt mixtures meeting the Virginia Department of Transportation (VDOT) mixture volumetric and gradation requirements for A and D mixtures. The initial performance criteria for the IDT-HT and RR tests were established for these mixtures. Based on the results, the IDT-HT test was found to be the most suitable alternative test to the APA test.

Mechanical characterisation of cementitiously stabilised moorum for use as structural layers in paving road construction

Due to the depletion of supplies for high-quality aggregates, it has become necessary to incorporate marginally soft materials like moorum in pavement structural layers. This study aimed to investigate the mechanical characteristics of cementitiously stabilised moorum materials (CSMM), which would be relevant during the mechanistic design of pavements. The tests includes the unconfined compressive strength, california bearing ratio in a soaked state, flexural strength, indirect tensile strength, durability and shrinkage behaviour through a comprehensive laboratory investigation procedure. In this investigation, the collected moorum sample was from Bihar, the eastern state of India. Relationships between various mechanical characteristics have been developed for pavement analyses. The properties are achieved as per standards to study the behaviour of the pavement structures. Based on the research findings, the effectiveness of the strength and shrinkage characteristics in determining the acceptability of CSMM as a road base and subbase applications have been discussed.

Uniform moduli characterization of asphalt mixtures under dynamic and static loading conditions

The modulus is a crucial material parameter reflecting stiffness characteristics of asphalt mixture in the elastic stage. Under specific conditions such as identical temperatures, loading velocities, and stress amplitudes, the moduli under the same stress state are theoretically identical. However, the moduli were artificially divided into dynamic moduli and static moduli based on loading methods during test, which brought uncertainties and disunity for estimating the stiffness performance of asphalt mixture. In this study, the dynamic and static moduli under distinct temperatures, loading velocities, and stress states were measured. The relationship between dynamic and static moduli was established by applying loading velocities as independent variable and moduli as the dependent variable. Through Sigmoidal function and WLF function fitting, the uniform characterization master curves of dynamic and static moduli under distinct temperatures, loading velocities, and stress states were established. The moduli of asphalt mixture under distinct test temperatures, loading velocities, and stress states can be obtained by the models, which provide material parameters for mechanical response analysis of asphalt pavements under distinct service environments. This resolves the issue of inconsistent moduli parameter selection.

Improving the Resilience of the Road Network in Algeria: A Comparative Analysis of Flexible, Geosynthetically Reinforced, and Rigid Pavements

Despite subsequent strengthening measures, pavements constructed in Algeria suffer rapid deterioration soon after completion, with continued decline in some cases. Various factors contribute to this problem, including cost and availability of materials, build quality, and environmental conditions. The entire Algerian road network is based on flexible and semi-rigid pavements. This study explores pavement structures using numerical predictive models to advance our understanding of road construction and maintenance. Using Abaqus 2022 finite element analysis software, we consider three scenarios: a simple pavement, a pavement reinforced with geosynthetics, and a rigid pavement. We compare the results concerning the vertical stresses, interface stresses, and vertical displacements at the level of the critical pavement sections. The aim of this research was to achieve behavior in flexible pavement similar to that of rigid pavement through the study of the reinforcement effect of flexible pavements with geogrids. The layers were treated as elastic, and a finite element analysis was conducted for various geogrid stiffness values (geogrid/soil stiffness ratios ranging from 1 to 50). The model enabled us to select the geogrid with the appropriate stiffness for each soil stiffness. The main conclusions are presented and discussed in depth, with the results confirming that rigid pavements offer greater strength and better durability. We then provide convincing evidence that the performance characteristics of rigid pavements can be obtained for flexible pavements by integrating a geogrid reinforcement system. This system is based on the choice of the stiffness ratio of the supporting soil and the rigidity of the geogrid. This option allows the state of the supporting soil to be accepted as it is and for intervention to target in the composite soil–geogrid rigidity.

Influence of Nonlinear Analysis Technology on Damage Analysis of Asphalt Pavement Structure

As a means of predicting the damage pattern and design life of asphalt pavement structures, the reliability of damage analysis is highly dependent on the calculation accuracy of the pavement mechanical responses under wheel load. The nonlinear analysis, on its part, can practically describe the stress dependence of the modulus of granular materials and fine-grained soils, so that the mechanical responses of the wheel-loaded asphalt pavement structure can be obtained more accurately. Therefore, the correct application of nonlinear analysis technology is essential to obtain reliable damage analysis results. For this reason, computer program KENLAYER was utilized to explore the effects of stress adjustment methods and core parameters of nonlinear iterative analysis on the damage analysis results. According to the calculation results, this paper explains the reasons why the stress adjustment Methods 2 and 3 are not applicable to the structural analysis of pavements containing nonlinear granular materials in the case of thin surface layers, illustrates the effects of improper selection of the adjustment methods and each iteration parameter on the dominant damage pattern, finds out the reasons for unreliable calculation results due to improper selection of the iteration parameters, and makes corresponding suggestions for carrying out damage analysis accurately.

Effect of using Oil Shale Ash on geotechnical properties of cement-stabilized expansive soil for pavement applications

Expansive soil is considered an engineering problem that may cause cracks and distresses in structures and roads. Due to its swelling potential and low unconfined strength, expansive soil causes failures in structures and leads to financial losses. Oil Shale Ash “OSA” is the byproduct of the combustion of the oil shale rock to produce electricity. Instead of dumping OSA materials into landfills, which has several negative environmental implications and cost burdens, utilizing these materials as building materials might alleviate the environmental concerns caused by their disposal. This research investigates the possibility of experimentally using the by-products Oil Shale Ash (OSA) and Portland Cement (PC) to enhance the geotechnical properties of problematic expansive soil. OSA and cement have been added to the soil, where OSA is used in four percentages by dry weight of soil (10%, 20%, 25%, 30%), and cement is used in three percentages (2%, 4%, 6%). A laboratory test program was implemented, including Atterberg limits, compaction test, unconfined compressive strength test (UCS), swell test, linear shrinkage test, and California Bearing Ratio (CBR) test. The results showed that OSA and cement have reduced the expansive natural soil's swelling potential, plasticity index, and linear shrinkage. Also, the UCS and CBR values of treated soil have improved significantly. Pavement analyses demonstrated that OSA-cement-stabilized soil could be a suitable stabilization agent for the subgrade and base layers in constructing pavements.

Analysis of Pavement Distresses Using the Image Processing Technique for Egyptian Roads

Analysis of Pavement Distresses Using the Image Processing Technique for Egyptian Roads

Mechanical behavior of asphalt pavement on steel-concrete composite beam bridge under temperature-load coupling

Over the past few decades, steel–concrete composite beam (SCCB) bridges have been gaining popularity all over the world. However, distresses such as rutting, delamination and cracking may occur on the corresponding bridge pavement structure soon after open traffic. To alleviate pavement distresses and clarify the applicability of different pavement structures and materials, in this study, a targeted research method for the mechanical properties of SCCB bridge deck pavement under temperature-load coupling was proposed. The research elements and procedures of the SCCB bridge deck pavement were structurally analyzed and synthesized. In addition, a temperature-load coupling model of SCCB bridge deck pavement was established. The permanent deformation under different cumulative axle load action times was calculated and fitted, and then compared with the actual detected data. Finally, the mechanical response of pavement structures commonly used for SCCB bridges was analyzed. The results show that the absolute error of rutting depth between the field test and fitting result was small, which proved the rationality of the proposed method. Besides, for SCCB bridges, “AC + SMA” and “double-layer SMA” have better road performance. The conclusion of this paper provides reliable support for the maintenance and distress causes analysis of SCCB bridge deck pavement.

Assessment of the impact of binder grade on the laboratory performance of fiber reinforced asphalt mixtures

This study aims to evaluate the impact of different fiber types and binder modifications on the volumetric properties and performance (rutting and cracking) of fiber-reinforced asphalt mixtures (FRAM). Four types of fibers (carbon, fiberglass, basalt, and polyolefin/aramid (PFA) mix) and two binder performance grades (PG 58–28 unmodified and PG 76–22 polymer modified) were used to produce a total of ten asphalt mixtures (two control and eight FRAM). All fibers were introduced at the manufacturer-recommended dosages (i.e., carbon, fiberglass, basalt: at 0.16%, and PFA: at 0.05%) by mix weight. The mix design and volumetrics properties were examined to assess the impact of FRAM on volumetric properties of modified and unmodified binders. Mix characteristics, durability, rutting, and cracking performances were also evaluated by performing several tests, including dynamic modulus test |E*|, Cantabro loss, Asphalt pavement Analyzer (APA), Flow Number (FN), and Indirect Tensile Asphalt Cracking Test (IDEAL-CT). Mix design results showed that FRAM at 0.16% dosage increased the air voids of the unmodified binder (PG58-28). PFA fibers did not have an impact on air voids or volumetric properties of the asphalt mix regardless of modification. Performance results showed that FRAM were highly durable than control mix, but durability is significant for polymer modified binder (PG76-22). Furthermore, only PFA reinforced mixtures showed better rutting resistance for both modified and unmodified binders. The addition of fibers did not show any impact on cracking performance of modified and unmodified binder prepared asphalt mix. Finally, PFA reinforced mix also indicated higher fracture toughness (Gf) and carbon fibers improved the ductility of asphalt mix.

Cold recycling mix design approach targeting permanent deformation resistance

Cold recycling technology offers a sustainable construction pathway for pavements with a potential of recycling up to 100% of the existing in-situ materials. This study introduces a new approach to design emulsion-based cold recycling mixtures. The proposed mix design approach channels the design efforts to optimize the mixture’s components and evaluate its long-term performance. The elements of the proposed design include altering aggregate gradation to achieve optimum packing; a method to selecting an optimum moisture content that is derived from both liquid components in the mixture; and selecting the residual asphalt content based on the mixture’s resistance to permanent deformation. To evaluate the reliability of the proposed mix design method, an optimum mixing water content was derived for an optimum RAP gradation. The effect of varying the emulsion content while keeping the mixing water content constant was evaluated on the mixture’s volumetrics, strength, and permanent deformation behavior. A conventional triaxial compression stress path was applied on samples compacted with several residual asphalt contents. The triaxial test results were compared with results obtained from Hamburg Wheel Tracking Test and Asphalt Pavement Analyzer rutting device. The increase in residual asphalt content at optimum mixing water content led to a systematic increase in strength and reduction in voids that stabilizes as the content increases. The permanent deformation experiments showed the importance of imposing a deformation criterion to select the residual asphalt content in the mix design stage. Additionally, the triaxial repeated load tests demonstrated the importance of using anticipated stress states to characterize permanent deformation resistance which cannot be captured by simple performance tests. Representative stress states in the CR layer should be taken into account during the mix design stage where higher stresses are anticipated in the recycled layer.

Comparative Analysis of Jointed Plain Concrete Pavement and Roller-Compacted Concrete Pavement

Jointed plain concrete pavement (JPCP) is the widely preferred conventional concrete pavement for highways; however, the higher initial construction cost and extended time for traffic opening limit its applicability. Recent advancements like roller-compacted concrete pavement (RCCP) could address the above concerns of JPCP. Yet, there is a lack of knowledge and comparative studies on the performance assessment, sustainability, and economic analysis of RCCP and JPCP. Therefore, this study aims to evaluate the engineering properties (density, compressive and flexural strength, and fluid flow properties), cost analysis (materials and initial construction cost), and sustainability (carbon dioxide emissions and energy consumption) of both pavements. The fresh density and mechanical properties of RCCP were 8%–9% and 13%–35% higher than JPCP; thus, 44%–89% and 24%–57% reductions in water absorption and porosity were observed in the considered RCCP mixes against JPCP. The higher strength properties of RCCP significantly reduced the pavement thickness by 10%–25%, thereby lowering the materials and initial construction costs by 52%–78%. Further, sustainability assessment through the cradle-to-gate (from raw material extraction to transportation phase) and gate-to-gate (only concrete production in a ready-mix plant) approaches revealed that employment of RCCP could significantly reduce carbon dioxide emissions (9%–30%) and energy consumption (10%–32%) compared with JPCP mixes. The findings show that RCCP can be considered sustainable, economical, and higher-performance pavement than JPCP.

Pavement sustainability: a tripartite analysis of natural stone pavements in Hanoi, Vietnam

As a basic component of the city’s structure and, particularly, an integral part of the transportation infrastructure, pavements fundamentally contribute to the city’s achievement of sustainability goals. This paper examines the environmental, societal, and economic impacts of using natural stone for the pavement to pursue an ideal image of Green-Clean-Beautiful city by the government in the burgeoning city of Hanoi, Vietnam. It addresses the urgent question of whether natural stone is a sustainable paving material in a tropical climate under the impacts of climate change. By analysing the published contents of the official press, supported by data and information gathered from interviews with key experts, stakeholders, and urban residents, this paper argues that the actual impacts of natural stone use for pavements on the environment, economy, and society are strongly negative, compared to the positivity initially perceived in Hanoi’s scheme of changing the pavement facelift. It shows that by overemphasising appearance and imagined nationalism values when selecting natural stone, Hanoi government shows a slow progress in improving and balancing functional, social, environmental, and economic dimensions. The paper is significant in contributing to knowledge on pavement sustainability and sustainable materials while shedding light on the challenges of applying these theoretical perspectives into real-life practice.

Reliability analysis of flexible pavements based on the quantile-value method

ABSTRACT This paper presents a simple yet efficient approach for the reliability-based design of flexible pavements, based on the concept of quantile-values. The reliability-based approaches currently adopted in the pavement design guides are simplified techniques, based on an overall reliability factor. On the other hand, simulation-based probabilistic techniques, widely discussed in literature, can be computationally expensive and tedious to implement. The ‘Simplified Effective Random Dimension Quantile Value Method’ (Simplified ERD-QVM), adopted in this study, presents an elegant technique to bridge the gap between the precision of simulation-based probabilistic techniques and the efficiency of design guide approaches. The accuracy of this technique is verified through Monte Carlo Simulations for different pavement design scenarios. The main advantages of the method are (i) the significant savings in computational times for reliability-based design of flexible pavements without the use of surrogate models (ii) the use of simple techniques already familiar to practitioners who adopt the Mechanistic-Empirical Pavement Design Guide and (iii) it is a comprehensive reliability analysis approach that addresses the drawbacks of the currently used approaches, while capturing the effect of both design parameter and model uncertainty. The methodology for integrating the Simplified ERD-QVM with the existing flexible pavement design codes is also presented.

Influence of roughness and cross slope induced dynamic loads on flexible pavement responses

ABSTRACT Among all the factors influencing flexible pavement design, vehicular loads are of prime importance. Thus the present study evaluates the dynamic wheel loads on the pavement by considering the prime factors related to the vehicle and the pavement. Relationships are developed for three different trucks considering the combined effects of vehicle speed, gross vehicle weight, and pavement roughness on dynamic loads. The study further quantified the effect of pavement cross slope on vehicular loading in the outer wheel path. Furthermore, the critical responses for a flexible pavement section are determined using finite element analysis by considering the viscoelastic properties of asphalt layers and moving loads. The findings of this study reveal that, even for a smooth pavement with roughness ranging between 1 and 2 m/km, the dynamic load can be 7–13% higher than the static weight. The dynamic loads further increase rapidly as the pavement deteriorates. Compared to the conventional static analysis, incorporating dynamic loads into pavement analysis revealed an increase in the critical responses by 6–50%. Further, due to the interplay between vehicle speed, dynamic load coefficient, effective load, dynamic modulus, and loading frequency, a non-linear decrease in critical responses is observed with increased vehicle speed.

A step toward improving management practices for airfield pavement infrastructures: a mechanistic-based analysis approach

Conventional performance indicators commonly used to evaluate airfield pavement infrastructures focus on surface condition assessment. However, the structural soundness of pavements remains a key element in determining the best intervention measures. Methods used worldwide to design and evaluate flexible airfield pavements are often based on the Multi-Layered Elastic Theory (MLET). The Federal Aviation Administration (FAA) also applies MLET to analyse data collected primarily with on-site Non-Destructive Testing (NDT). However, material behaviour is not always aligned with MLET assumptions. In this study, pavement analysis results are investigated from a mechanistic view considering, in particular, the viscoelastic properties of Asphalt Concrete (AC). The analysis is performed using NDT and coring data collected in-situ from a runway considering variable aircraft loading and moving speeds. Based on the response status at both critical locations of a flexible pavement plus its surface, it is observed that MLET appears to be less conservative at normal operating speeds, where higher pavement damage is expected. In addition, an integration potential of viscoelastic strains and NDT data is shown, which can accelerate the pavement evaluation process. It is expected that the presented approach can provide a framework for improving airfield pavement management practices.

Deflection-Based Approach for Flexible Pavement Design in Thailand

The Department of Highways (DOH), Thailand, has adopted both empirical and mechanistic approaches for flexible pavement analysis and design. Recently, the deflection-based design approach has been comprehensively reviewed by the DOH for the possible adoption of national design standards and practices. One of the key reasons is that Thailand’s road authorities, i.e., the DOH and the Department of Rural Roads (DRR), have considered the falling weight deflectometer (FWD) for the new construction and rehabilitation of road pavements. In addition, the FWD is widely accepted as the non-destructive test for deflection measurement and structural capacity evaluation. Ultimately, the implication of FWD deflections for in-house pavement analysis and design shall be developed and proposed to Thailand’s road authorities. Therefore, this study presents the deflection-based approach of flexible pavement design in Thailand. The FWD and a standard Thai truck were selected as the main loading applications in this study. A typical FWD loading stress of 700–800 kPa was practically adopted by the DOH and compared with a standard 10-wheel 25-ton truck with a tandem axle-dual wheel configuration with a tire pressure of 690 kPa. The layered elastic analysis was performed to calculate the pavement responses. The results suggest that the flexible pavement design based on a deflection-based approach is simple, practical, and conservative.

Thermo-vibro-acoustic analysis of pavement under a harmonically rectangular moving load

This study presents an analytical framework based on the third-order shear deformation theory (TSDT) to conduct a comprehensive thermo-vibro-acoustic evaluation of a multi-layered asphalt system subjected to a harmonically rectangular moving load. The research aims to investigate the dynamic response and sound radiation characteristics of the pavement under various operating conditions. The materials and methods employed in this study are as follows: The temperature variations along the thickness axis of the layers are considered, and Hamilton's principle is adopted to derive the governing equations in the time-based domain. The equations are then solved in the Laplace domain using the Fourier series and the Laplace transform. The acoustic pressure generated by the moving load is investigated by applying Durbin's numerical Laplace transform inversion technique and analyzing the Rayleigh integral. The accuracy and flexibility of the proposed approach are demonstrated through comparisons with previous studies and finite element (FE) simulations using COMSOL Multiphysics®. Finally, a comprehensive analysis is conducted to examine the impact of various factors, including the frequency and velocity of the moving excitation load, the viscoelastic medium, and variations in temperature, on both the dynamic response and sound radiation of the pavement. Some of the major findings of this research are as follows: An increase in load velocity leads to a higher frequency of pressure waves and closer spacing between them, resulting in elevated sound pressure amplitude. Higher pavement temperatures cause increased softness and rutting depth under moving loads. This research offers a novel and practical contribution to the field of pavement systems by presenting an analytical framework for a comprehensive thermo-vibro-acoustic evaluation and providing valuable insights into the dynamic response and sound radiation characteristics of multi-layered asphalt systems under various operating conditions.

Modal analysis of rigid pavement resting on two-parameter soil foundation model using finite element framework

PurposeThe purpose of this study is to numerically model the rigid pavement resting on two-parameter soil and to examine its modal parameters.Design/methodology/approachThis study is carried out using a one-dimensional beam element with three rotational and three translational degrees of freedom based on the finite element method. MATLAB programming is used to perform the free vibration analysis of the rigid pavement.FindingsCyclic frequency and their corresponding mode shapes were determined. It has been investigated how cyclic frequency changes as a result of variations in the thickness, span length of pavement, shear modulus, modulus of subgrade, different boundary conditions and element discretization. Thickness of the pavement and span length has greater effect on the cyclic frequency. Maximum increase of 29.7% is found on increasing the thickness, whereas the cyclic frequency decreases by 63.49% on increasing span length of pavement.Research limitations/implicationsThe pavement's free vibration is the sole subject of the current investigation. This study limits for the preliminary design phase of rigid pavements, where a complete three-dimensional finite element analysis is unnecessary. The current approach can be extended to future research using a different method, such as finite element grilling technique, mesh-free technique on reinforced concrete pavements or jointed concrete pavements.Originality/valueThe finite element approach adopted in this paper involves six degrees of freedom for each node. Furthermore, to the best of the authors’ knowledge, no prior study has done seven separate parametric investigations on the modal analysis of rigid pavement resting on two-parameter soil.

Summarizing the Effect of Mixture Variables and Test Parameters on Fatigue Performance of Asphalt Mixtures

Abstract Fatigue cracking performance of asphalt mixtures is significantly affected by mixture variables and environmental and loading conditions in the field. Thus, there is a need to understand the effect of critical factors on the fatigue cracking resistance of asphalt mixtures through an extensive study. For this purpose, the present research is focused on characterizing fatigue cracking resistance of asphalt mixtures by considering different factors such as aggregate gradations (two dense and two gap gradations), binder types (two unmodified and three modified binder types), binder content (optimum binder content and optimum binder content ±0.5 %), test temperatures (15°C, 25°C, and 35°C), and three stress levels for different asphalt layer thicknesses (40, 80, 120, 160, 200, and 240 mm). An indirect tensile fatigue test was performed to characterize fatigue cracking resistance of asphalt mixtures, and a Kaplan–Meier survival analysis was carried out to examine whether the factors that were considered significantly affected the fatigue performance. Pavement sections with varying thicknesses of asphalt layers were analyzed using IITPAVE, a pavement analysis software, to compare the mixtures’ fatigue performance. All of the variables taken into consideration in this study were shown to have a statistically significant effect (p value < 0.05). However, the binder type had a stronger influence than the other variables on the resistance to fatigue cracking. Finally, a fatigue life equation (adjusted R2 = 0.77) was developed considering all the mixture combinations, which can be used for determining the laboratory fatigue life of asphalt mixtures.

Research of a Fiber Sensor Based on Fiber Bragg Grating for Road Surface Monitoring

Road infrastructure is a key public asset because it benefits the social and economic development of any country. It plays an important role in the development of the industrial complex and the production sector, and the surfaces of transport roads should be of high quality and have a long service life. Road infrastructure, like all infrastructure, requires preservation, maintenance and repair. There are special requirements for roadways that must be observed during construction or repair. The uncertainty of the composition, temperature sensitivity and viscoelastic characteristics of road materials make the structural analysis of pavement very difficult compared to other civil structures, such as bridges, tunnels and buildings. For this reason, the question of how to improve fiber sensors based on fiber Bragg grating (FBG) arose. The novelty of this study is to modernize fiber sensors based on FBG so that they display deformation, stress and displacement, temperature and other parameters with much greater accuracy, which would provide a reliable scientific basis for modifying the theory, as well as the use of a fiber sensor based on FBG for simultaneous measurement of deformation and temperature when monitoring the road surface. This article is devoted to a detailed study of the use of fiber-optic sensors (FOS) based on fiber Bragg grating for road surface monitoring. Such a fiber sensor, consisting of a fiber Bragg grating and a pair of grids, can offer the possibility of simultaneous measurement of deformation and temperature for monitoring the pavement. Temperature and deformation measurements were carried out by installing a sensor on the surface of a made asphalt sample. The built-in fiber sensor based on FBG provides important information about how the pavement structure can withstand the load and subsidence of soil and implement road safety and stability measures in a timely manner to evaluate and predict the service life of the pavement. The results of the study showed that the synchronicity, repeatability and linearity of the characteristics of the fiber sensor are excellent. The difference between the experimental and theoretical results was about 7%. Thus, based on the results of the obtained data, the fiber sensor on the FBG can be used for monitoring and designing road surfaces and in general transport infrastructure.