Pavement Life Cycle Research Articles

The influence of Multi-Layer Plastic Packaging (MPP) on the high-temperature performance of asphalt binders and mixtures using wet and dry mixing methods

ABSTRACT High temperatures, combined with heavy traffic loads, increase the risk of permanent deformation and reduce the useful lifespan of pavements, leading to a greater need for maintenance and rehabilitation activities throughout the pavement's service life. This study aims to evaluate the effectiveness of recycled thermoplastic additives, specifically Multi-Layer Plastic Packaging (MPP) materials, in enhancing the high-temperature performance of asphalt mixtures. MPP materials, including types such as Polyester, Polyethylene, Nylon, and Metalized Polyester, were used for binder modification in asphalt mixtures. The modification was conducted using both wet and dry methods. The physical and rheological properties of the modified binders were assessed at high temperatures to determine their impact on stiffness and resistance to permanent deformation. The results indicate that MPP materials significantly improve the high-temperature performance of asphalt mixtures by enhancing binder stiffness and resistance to permanent deformation, with the wet method proving more effective than the dry method. These findings highlight the need for developing practical guidelines for incorporating MPP materials in asphalt production in the future and underscore the importance of comprehensive studies on maintenance, rehabilitation, and overall pavement lifecycle costs.

Materials Carbon Budget in Road Projects: A Case Study from The Greater Oslo Region

The estimation of carbon dioxide emissions in relation to the life cycle of road pavements is pivotal to quantify their sustainability at the design stage. This preliminary study assesses the carbon budgets concerning the production of aggregates and asphalt to build a new roadway stretch located close to Oslo (Norway), leveraging digital tools and environmental product declarations. First, the software Trimble Novapoint estimates the necessary quantity take-offs. Afterwards, the amounts of CO2 generated during the production of the construction materials are appraised for the four main industries operating nearby. The results based on the corresponding environmental product declarations indicate that the carbon budgets show very small discrepancies among the considered suppliers.

Development of a streamlined framework for probabilistic and comparative life cycle assessment of road pavements

This study presents a novel framework to address the challenges of extensive data requirements and uncertainties in road pavement life cycle assessment (LCA). We introduce a streamlined framework that employs a structured data underspecification approach. In this study, we categorized the required data into four specificity levels (M1 to M4) to manage data uncertainty in a systematic way. Using 10 case studies with various data specificity levels, our method proves effective in adapting to different degrees of data scarcity. The proposed framework supports a confident decision-making process, in which the comparison indicator shows discerned results at least 90 % of Monte Carlo runs by reducing the data collection burden by 85.7 %. For example, in the Boston pavement scenarios, one can achieve a 90 % reliability level by selectively specifying the maintenance and repair (M&R) activities to an M3-level specificity, while maintaining all other data at a lower level of detail, i.e., M2.

ANALISIS LIFE CYCLE COST PERKERASAN KAKU DAN LENTUR JALAN PROVINSI (STUDI KASUS: JALAN RAYA PARE – KEDIRI)

Pare-Kediri Highway is a provincial road which is the main connecting road between Pare and Kediri City. On this road section is often bypassed by vehicles with large loads. However, in existing conditions there is damage that varies. Road planning is generally planned to be used for a certain period of time, for example 10 to 20 years depending on existing transportation needs, in the hope that the road will remain in good condition and suitable for traffic. Road maintenance measures are necessary to ensure good operating conditions throughout the planning period. Maintenance and repair of damaged roads also cost a lot. As a result evaluating road damage and choosing the right type of repair is very important. According to the results of research with the 2017 pavement Design Manual guidelines, flexible pavement thickness was obtained including AC-WC 4 cm, AC-BC 6 cm, AC-Base 16 cm and Class A aggregate foundation layer 15 cm. While the thickness of the rigid pavement using continuous concrete without reinforcement with 30 MPa quality concrete obtained plate thickness of 28.5 cm and a layer of thin concrete foundation (LMC) 10 cm. Based on data processing, the construction cost of flexible pavement amounted to Rp 12,958,812,587.00 while rigid pavement amounted to Rp 30,584,262,345. 00. The Total maintenance cost for flexible pavement is Rp 23,836,678,414.33 while for rigid pavement is Rp 3,208,462,265. 15. So that the results of life cycle cost analysis of this study obtained the total cost during the 20-year life cycle of flexible pavement of Rp 36,795,491,001.33 while rigid pavement of Rp 33,792,724,610. 15. In this case, rigid pavement has a life cycle cost (life cycle cost) which is 8.51% more efficient than flexible pavement.

Reimagining unbound road pavement technology: Integrating testing, design, construction and performance in the post-digital era

The Industry 4.0 revolution signifies a pivotal transition in pavement technology, emphasising the integration of digital and physical systems to revamp traditional, empirical-based pavement design, construction, and maintenance practices. This shift promises enhanced efficiency, sustainability, and a move towards integrated practices, highlighted by adopting “Digital Twin” technology. Unlike traditional Building Information Modeling (BIM), Digital Twin technology offers a real-time, dynamic representation of physical infrastructure, enabling improved asset management through distributed sensing and predictive performance analytics. Leveraging findings from the Australian Research Council (ARC)’s Industry Transformation Research Hub for Smart Next Generation Transport Pavements (SPARC Hub), this paper focuses on the integration of pavement testing, design, construction, condition assessment and asset management into the lifecycle of unbound road pavements. The paper outlines how such technological integration streamlines decision-making processes and significantly boosts the functionality and longevity of pavement infrastructures. Despite facing challenges like cost, data security, and the need for specialised skills, the potential for digital technologies to improve pavement durability, efficiency, and sustainability is significant. Future research directions are identified to overcome implementation barriers, explore untapped technological potentials, and assess the sustainability benefits of digital approaches in pavement engineering, aiming to forge more resilient, efficient, and sustainable road networks for future generations.

Analysis of the extent of heavy vehicle overloading on Namibian trunk roads and evaluation of the effectiveness of existing mitigation measures

Overloading of heavy vehicles reduces pavement life and increases pavement life cycle costs. As part of Namibia's strategy to control heavy vehicle overloading on the road network, weighbridge facilities have been constructed at strategic locations on primary routes (trunk roads). The study analysed the extent of heavy vehicle overloading on Namibian trunk roads, as well as the effectiveness of existing overloading mitigation measures. The dataset comprised heavy vehicle loading information from the year 2015 to 2019, from ten static weighbridge facilities. The parameters investigated include overloading magnitude, the effect of overloading on road pavement life, and the effectiveness of current overload mitigation measures. The results showed that 13.3% of the vehicles weighed were overloaded, with a compounded decrease in overloading of approximately 0.5% per annum. Despite the overloading decrease, the study found that the estimated road service life was reduced by as much as nine years over the study period. High levels of weighbridge avoidance and poor stakeholder coordination in mitigating overloading were identified. The study recommends deploying high-speed weigh-in-motion systems, an increase in fines charged for overloading offenses, and developing a demerit point-based system for habitual offenders to strengthen mitigation measures.

Effect of Traffic and Soil characteristics on Flexible and Rigid Pavement Life Cycle Costs

Effect of Traffic and Soil characteristics on Flexible and Rigid Pavement Life Cycle Costs

Performance and Lifecycle of Hot Asphalt Mix Modified with Low-Percentage Polystyrene and Polybutadiene Compounds

The paper investigates the improvement of bitumen mixture fatigue resistance and the rutting performance by using a specific low percentage of a styrene–butadiene–styrene (SBS) polymer, which contains polystyrene and polybutadiene compounds. A Fourier transform infrared (IR-FT) spectroscopy of the SBS polymer used in following test was carried out to ascertain the polybutadiene and polystyrene compound ratio, which may affect the modificant properties. Unmodified, low-percentage modified SBS, and common polymer-modified bitumen (PMB) as a reference were tested to ascertain the properties, fatigue resistance, and the rutting performance. The test results of the low-percentage modification with SBS are compared against unmodified mixtures and standard PMB mixtures. Finally, a simulation of the practical application was performed using the HDM-4 software (version 2.0), where the material research findings, with an emphasis on the rutting performance, were translated into the pavement performance with a varying binder course layer under simulated traffic conditions. Lifecycle analysis, with a focus on emissions production (CO2, SO2, and NOx) during pavement operation, was conducted for pavements with unmodified, low-percentage modified SBS, and standard PMB binder courses. The lifecycle analysis showed that a 3% modification of the binder course with the SBS polymer can extend the rutting parameter pavement lifecycle by approximately 34.5%, which is about half of the extension provided by the standard PMB modification. The resulting improvement in the pavement serviceability translated to a 9% reduction in CO2 and SO2 emissions and a 7.2% reduction in NOx emissions over a 20-year period.

Adaptive maintenance strategies to mitigate climate change impacts on asphalt pavements

This study aims to explore the potential of optimization-based maintenance strategies in adapting asphalt pavements to future climate change. Based on a highway network in Jiangsu, China, the impacts of climate change, characterized by global warming and intensified precipitation, on pavement life cycle cost (LCC) and performance were quantitively assessed, and the benefits of maintenance optimization in mitigating climate change impacts were examined. The findings indicate that climate change may increase pavement rutting depth and reduce pavement roughness and skid resistance, while its effect on transverse cracking varies over time. Adjusting the maintenance schedules, but still following the threshold-based approach, would increase the LCC by about 15.5 %∼19.1 %. The optimization-based maintenance decision-making model significantly mitigates climate change impacts, ultimately even saving 0.6 % of LCCs compared to the baseline. The outcomes will provide a quantitative understanding of the climate change impacts on asphalt pavements, as well as adaptive maintenance strategies to improve pavement resilience.

Assessment of microplastics production from waste plastics-modified asphalt pavement

Post-consumer recycled plastics (PCRP) have been increasingly utilized in asphalt pavement applications as the world moves towards a circular economy. However, it is unknown whether microplastics (MPs) could be generated in significant amounts during the subsequent pavement life cycle. This study developed methods to detect and quantify the potential microplastic generation from asphalt pavement materials containing PCRP (specifically, linear low-density polyethylene) using the Hamburg wheel-tracking test and a water permeability test. MPs were quantified by Nile Red staining followed by fluorescence microscope imaging. Environmental scanning electron microscopy (ESEM) and energy dispersive spectroscopy (EDS) were further conducted to characterize the nanoscale morphology of the embedded PCRP. The results showed that the generated MPs could reside at water/air interface, in bulk water, or with asphalt binder and aggregates in the sediment; and their amounts varied depending on the polyethylene dosage and type. The potential environmental impact of MP production from PCRP-modified asphalt pavement needs to be examined under the context of MP particle releases from other emission sources, notably, the tire wear particle generation when rubber tires meet the road. Our assessment indicated that while there was a potential of MPs release from the PCRP-modified asphalt, the up-scaled level of their release from a pavement was estimated to be about three orders of magnitude less than the tire wear rubber particles.

Carbon emissions quantification and different models comparison throughout the life cycle of asphalt pavements

Establishing a comprehensive and systematic method for quantifying carbon emissions (CEs) of asphalt pavement is challenging due to the multifaceted and diverse nature of the involved processes. Utilizing a life cycle assessment framework, this study introduces a practical model system for capturing CEs across the entire lifespan of asphalt pavement. A pivotal aspect of our approach involves calculating activity levels. Material quantities are ascertained based on mixture proportions and specific pavement information. We employ Ridge Regression and the quota method to approximate the energy consumption of construction machinery. A comparative analysis is performed between two CE computation models that use energy consumption and operational time as activity levels, respectively. Additional vehicle fuel consumption is translated based on shifts in the International Roughness Index, as predicted by the Mechanistic-Empirical Pavement Design Guide. CEs from traffic disruptions are calculated collaboratively through VISSIM simulations and MOVES emission modeling. Our findings reveal that material production, mixture preparation, and maintenance duration are the principal factors contributing to CEs throughout the asphalt pavement lifecycle. Notably, emission estimates for machinery in the construction phase can vary by as much as 8.3 times across different models. The study suggests that incorporating the use of recyclable materials and designing more durable pavement structures can offer effective avenues for CE mitigation.

Investigation of the combination of microwave heating and calcium alginate capsule rejuvenation healing methods for cold mix asphalt considering the type of compaction effort

Healing behavior of asphalt mixes can affect the pavement life and life cycle cost. Effects of encapsulated rejuvenators and microwave heating methods (as two approaches to improve self-healing behavior) on the cold mix asphalt (CMA) were studied separately and simultaneously at different compaction conditions (i.e., different types and levels of compaction). For this aim, capsules of calcium alginate (CAG) loaded with waste sunflower oil (WSO) and waste engine oil (WEO) were used as encapsulated rejuvenators and iron (Fe) powder was used as a heat conductive material to spread microwave heating into the samples. Moreover, the synergetic effect of powder-based heat-absorbing additives and encapsulated rejuvenators on the healing performance (HP) was also investigated. The chemical test results showed that the Fe powder is compatible with the bitumen emulsion. Pre- and post-healing semi-circular bending (SCB) fracture experiments were conducted before and after healing to check for the effect of the healing method and compaction effort on the HP of CMA. The results indicated higher effectiveness of the microwave heating rather than the encapsulated rejuvenators for facilitating the healing of cracked areas in asphalt mixes. Combining microwave heating and encapsulated rejuvenation methods was not successful in improving the HP, and the healing index was reduced 10 to 15% when both methods were combined. Compaction condition was more influential than the healing method, and the adverse impact of inadequate compaction could not be compensated with any healing methods. It was shown that the healing index can be improved by more than 10% when a proper compaction was applied to the specimens.

The Application of Bio-Emulsion from Soybean Oil Partially Epoxidized as a Maintenance Technique for Flexible Pavements

Abstract An increase in the use of biomaterials has been noted in recent years because of several impacts caused by human activities, especially for engineering and paving industry benefits. Several renewable resources, such as a nonfood source of soybean oil, have been successfully tested on modification of asphalt binders. However, their impact on the pavement life cycle is still unknown. Thereby, the objective of this research was to investigate soybean oil as a new, green supply for the maintenance of flexible pavements. The experimental plan consisted of the construction of field test sections through the application of sub-epoxidized soybean oil (SESO) over a flexible pavement surface. Rates of 0.1 and 0.3 L/m2 were chosen, and the main tests intended for study were functional procedures including the British pendulum and sand patch tests on the pavement surface, which were complemented with the indirect tensile strength test for mechanical analysis. The change in the chemical composition of the recovered binder was analyzed by thin layer chromatography and Fourier-transform infrared spectroscopy. The rheological properties were analyzed by frequency sweep, linear amplitude sweep, and multiple stress creep and recovery, and the tests were carried out with a dynamic shear rheometer. The effects of the SESO bio-emulsion demonstrated a rejuvenating activity on the properties of the aged binder, with mechanical and rheological improvements for both analyzed rates. A further investigation is indicated to evaluate the influence of time on the modification studied in this work. Such testing could ensure the use of SESO bio-emulsion as an environmentally friendly alternative for the maintenance of flexible pavements.

Assessing the effects of unit cost uncertainty on flexible road pavement economics under the influence of climate change

Pavement researchers typically adopt life cycle cost analysis (LCCA) to quantify changes in the economic performance of road pavements due to the effects of climate change. As uncertainty exists in the unit cost of materials, fuels, and machinery operation, the assessment of climate change-induced pavement costs invariably involves uncertainty. If such uncertainties remain unaddressed, the assessment of pavement costs will not be accurate. Therefore, this study develops a stochastic pavement LCCA framework to account for the effects of such uncertainties on climate change-induced pavement life cycle cost. This is achieved by integrating a sensitivity analysis methodology and Monte Carlo simulation. To demonstrate the applicability of the framework case studies are performed for standard interstate and standard primary road pavement sections in four climate zones in the United States under a high climate change Representative Concentration Pathway (RCP8.5) for four different periods between 1981 and 2100. The results show that pavement maintenance, end-of-life (EOL), and transportation costs are most affected by climate change. To assess climate change-induced pavement costs more accurately, it is important to improve the accuracy of gasoline, diesel, and hot mix asphalt (HMA) unit costs, as they are the most sensitive input to the pavement LCCA model.

Environmental and Economic Efficiency of Stone-Matrix Asphalt with Surface Micro-Milling

The Georgia Department of Transportation (GDOT) has employed a combination of open-graded friction course (OGFC) and stone-matrix asphalt (SMA) layers on its Interstate highways for more than two decades. Given that the SMA layer was structurally intact, GDOT implemented micro-milling to solely remove the OGFC layer. Four conventional resurfacing cycles were considered to compare the environmental and economic impacts for a section of Interstate 95 using life-cycle assessment and life-cycle cost analysis, assuming 8-, 10-, 12-, and 14-year resurfacing intervals of asphalt concrete (AC) resurfacing. Within the pavement life cycle, the maintenance and rehabilitation (M&R), and the use stages were significantly influenced by the change of scenarios. The M&R stage revealed a twofold cost increase for the full-depth AC, as compared with SMA, over the pavement life, because of the latter’s relative improved structural performance and a delay in future rehabilitation. Furthermore, in the use stage, M&R affected the agency costs significantly, whereas the work-zone delay governed the user cost. The holistic evaluation of the SMA and micro-milling combination revealed positive outcomes in field performance, along with environmental and economic impacts. However, it is worth noting that the scenarios presented follow GDOT’s approach with a long-standing use of SMA and micro-milling. Given the extensive experience with the aforementioned combination, it was evident that the method provided significant benefits, especially in the long-term outlook, and may be applicable for locations that have conditions analogous to GDOT’s.

Life cycle assessment of greenhouse gas emissions with uncertainty analysis: A case study of asphaltic pavement in China

There are a large number of complex uncertainties in the road life cycle assessment (LCA) analysis process and ignoring these uncertainties will lead to biased results and decision-making. To improve the accuracy of the quantification of carbon emissions (CEs) over the life cycle of pavements, a system for quantifying uncertainty was developed and a case study was conducted in conjunction with sensitivity analysis. The data quality index (DQI) combined with the beta distribution method was implemented to assess parameter uncertainty. The uncertainty of the model parameters was characterized using the results of slice sampling. The uncertainty in the shape of the model was described by the difference before and after the correction of the Hermite orthogonal polynomials. Various uncertainties are conveyed by the Monte Carlo simulation sampling method. To provide reliable emissions data, VISSIM and MOVES were used to calculate additional CEs from congestion. This study assesses the uncertainty of a specific road LCA case. The results show that uncertainty in model form has the greatest impact on results. The use and maintenance phases are key stages for improving the reliability of pavement life cycle CEs, with CEs and uncertainty contributions of around 90% and 94% respectively. The time-triggered conservation strategy has a 75% probability of dominance. This study provides a comprehensive theoretical basis for improving the quality of road LCA CE results, and also makes recommendations for the development of green and low-carbon road engineering.

Quantitative assessments of GHG and VOCs emissions of asphalt pavement contained steel slag

Using steel slag aggregate in asphalt pavement is recognized as novel alternative to enhance the environmental benefits, however, lacking quantitative analysis on its air components emissions largely hinders the fulfilment of sustainable road development. The study conducted the comparative research for the steel slag and the natural aggregate asphalt pavement from asphalt volatile organic compounds (VOCs) and greenhouse gas (GHG) emissions. The self-assembled gas generator and gas chromatography-mass spectrometer (GC–MS) were used to study the characteristics of asphalt VOCs. Moreover, the GHG emissions of asphalt pavement life cycle have been quantified with a prospective life cycle assessment (LCA). Different from traditional cognition, the research results showed that using steel slag aggregate in asphalt mixture would cause more asphalt VOCs and GHG emissions than natural aggregate in the life cycle of asphalt pavement. Specifically, comparing to the natural aggregate, the asphalt pavement contained steel slag aggregate generated extra 2 % to 30 % concentrations for primary VOCs components, and 11.86 t equivalent CO2 in the 20-year life cycle of asphalt pavement. The study provides valued reference for air pollution controlling and low-carbon development of asphalt pavement.

Study on the evolution of airport asphalt pavement integrated distress based on association rule mining

In order to better investigate the relationship between airfield asphalt pavement distress, 500 units of asphalt runway data were obtained from a scientific pavement zoning method for five airports, based on an extensive collection and survey of asphalt pavement distress types and damage levels. An improved Apriori algorithm was used to explore the evolution mechanism between typical distress, to establish a pavement evolution model and to characterize the distress deterioration probability by defining the deterioration degree. The data mining results show that there are three stages of asphalt pavement distress evolution, and that each distress can evolve from the previous distress. The key to extending the service life of asphalt pavement lies in delaying and stopping the process of distress evolution and accurately judging the key points of distress evolution from the perspective of pavement maintenance plans for the whole life cycle of pavement, which provides a scientific basis for further management of a preventive maintenance evaluation index system for asphalt pavements.

Leveraging Infrastructure BIM for Life-Cycle-Based Sustainable Road Pavement Management.

The latest developments in the field of road asphalt materials and pavement construction/maintenance technologies, as well as the spread of life-cycle-based sustainability assessment techniques, have posed issues in the continuous and efficient management of data and relative decision-making process for the selection of appropriate road pavement design and maintenance solutions; Infrastructure Building Information Modeling (IBIM) tools may help in facing such challenges due to their data management and analysis capabilities. The present work aims to develop a road pavement life cycle sustainability assessment framework and integrate such a framework into the IBIM of a road pavement project through visual scripting to automatically provide the informatization of an appropriate pavement information model and evaluate sustainability criteria already in the design stage through life cycle assessment and life cycle cost analysis methods. The application of the proposed BIM-based tool to a real case study allowed us (a) to draw considerations about the long-term environmental and economic sustainability of alternative road construction materials and (b) to draft a maintenance plan for a specific road section that represents the best compromise solution among the analyzed ones. The IBIM tool represents a practical and dynamic way to integrate environmental considerations into road pavement design, encouraging the use of digital tools in the road industry and ultimately supporting a pavement maintenance decision-making process oriented toward a circular economy.

Identifying environmentally sustainable pavement management strategies via deep reinforcement learning

Pavement life cycle assessments (LCAs) enable decision-makers to evaluate the environmental impact of alternative maintenance, rehabilitation, and reconstruction strategies. This paper explores the viability of deep reinforcement learning (DRL), a framework that enables agents to learn optimal actions within a given situation, to identify environmentally benign pavement management strategies. More specifically, this study utilizes proximal-policy optimization (PPO), a subtype of DRL algorithms, to identify a management strategy that minimizes the expected global warming impact of a pavement facility over its lifecycle. Through an urban Interstate case study, this paper shows that the proposed PPO algorithm identifies management strategies that are anticipated to reduce the expected global warming impact of a pavement facility over its planning horizon by 16 percent relative to traditional practice. Furthermore, the PPO algorithm is able to identify this management strategy in only 25 learning iterations, which is in stark comparison to Q-learning, a common reinforcement learning algorithm, that requires 70,000 learning iterations. The results of this work highlight the viability of DRL to integrate within complex LCA models to determine environmentally sustainable pavement management strategies.