Pavement Applications Research Articles

Performance Assessment of Eco-Friendly Asphalt Binders Using Natural Asphalt and Waste Engine Oil

The depletion of petroleum reserves and increasing environmental concerns have driven the development of eco-friendly asphalt binders. This research investigates the performance of natural asphalt (NA) modified with waste engine oil (WEO) as a sustainable alternative to conventional petroleum asphalt (PA). The study examines NA modified with 10%, 20%, and 30% WEO by the weight of asphalt to identify an optimal blend ratio that enhances the binder’s flexibility and workability while maintaining high-temperature stability. Comprehensive testing was conducted, including penetration, softening point, viscosity, ductility, multiple stress creep recovery (MSCR), linear amplitude sweep (LAS), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). The results reveal that WEO effectively softens NA, improves ductility, and enhances workability, with the 20% WEO blend achieving the best balance of physical and rheological properties. Chemical analysis indicates that WEO increases carbon content and reduces sulfur and impurities, aligning NA’s composition closer to PA. However, excessive WEO (30%) compromises thermal stability and deformation resistance. The findings underscore the potential of WEO-modified NA for sustainable pavement applications, with 20% WEO identified as the optimal content to achieve performance comparable to conventional petroleum asphalt while promoting environmental sustainability.

Optimization and characterization of lime and GGBS treated fly ash for sustainable road pavement applications

Optimization and characterization of lime and GGBS treated fly ash for sustainable road pavement applications

Eco-friendly stabilization of clayey soil with waste glass powder-based geopolymer

ABSTRACT This research studied the feasibility of using waste glass powder, Portland cement, and sodium chloride to stabilise and geopolymerization clayey soil. The chemical composition and microstructure of the materials were determined by X-ray fluorescence and scanning electron microscopy, respectively. Cement and waste glass powder contents were determined through previous laboratory tests and literature reviews. Unconfined compressive strength tests were performed to determine the optimal sodium chloride content, which was used in this research as an alkaline precursor in geopolymer formation. The effects of cement, waste glass powder, and geopolymer (composed of soil+(5 and 15% waste glass powder)+1% sodium chloride) were investigated through unconfined compressive strength and splitting tensile strength tests. The results revealed that the specimens stabilised with geopolymer presented higher strengths, finding strengths approximately 24 times higher than the pure soil and 1.6 times higher than the soil stabilised with 8% cement. Adding waste glass powder and geopolymer allowed some blends to become suitable for use as a subbase in pavement applications. Microstructure analyses confirmed the formation of geopolymer through a more homogeneous structure. Finally, it was concluded that stabilising with geopolymer based on waste glass powder is an ecological and effective technique for increasing soil strength.

Soil-aggregate-cement mixtures for base pavement layers: A strength and stiffness characterization

Pavements subjected to high volume load require a robust structure. In Brazil, cemented base layer is usually used instead of asphalt concrete thick layer due to cost issues. Soil-aggregate-cement (SAC) mixture is an alternative in pavement application, but the lack of design and dosage protocols hinders the understanding of the parameters influencing its mechanical behavior. This study presents a mechanical characterization of SAC mixtures in terms of strength (UCS and ITS) and stiffness (Mr), focusing on integrating the needs of pavement design to dosage purposes. For this, different SAC mixtures are produced, varying the soil-aggregate proportion (30:70 and 20:80) and cement content (3, 5 and 7 %). Mechanical properties were measured on cured mixtures at 0, 7 and 28 days and compared to structural responses of hypothetical pavements computed by mechanistic analysis. The results indicate a potential for using SAC mixtures in base layers due to their higher strength and stiffness. Predictive models relating ITS x UCS, Mr x UCS, and Mr x ITS with good statistical fit were proposed to assist researchers and engineers in selecting mixtures more adequate and durable for pavement applications, based on the concept of limiting the tensile stress acting on the cemented base course.

Ultra-high performance concrete with high strength, workability, loading durability and low curing maintenance for applications in airport pavement

With the rapid development of the aviation industry, airport pavement is subjected to ever-increasing loads, posing urgent and higher demands on the mechanical performance and durability of pavement materials. This study develops a novel Ultra-High Performance Concrete (UHPC) with outstanding mechanical properties, good workability, low curing maintenance, and excellent performance in sustaining long-term load to specially designed for its potential application in airport pavement. The as-developed UHPC contains a mixed portion of fine and coarse aggregate, assuring its workability and avoiding the early-age shrinkage crack for the potential on-site construction. With a 7-day compressive strength of 140MPa, compressive strength of 155.1MPa, flexural strength of 25.4MPa at 28 days, and a wear loss per unit area of 0.043kg/m2, the mechanical properties of UHPC well outperform those of conventional C30 airport pavement concrete. Finite element simulation analysis reveals that a 10cm thick UHPC surface layer demonstrates durability and safety under aircraft taxiing and landing impact loads, with a maximum tensile stress of 4.12MPa well below its tensile strength limit of 8.75MPa. Furthermore, it is predicted that a 10cm thick UHPC overlay could support a load cycle lifespan 1014 times longer than that of conventional C30 concrete of 30cm thickness, indicating its potential to significantly extend the service life of airport pavement. This research provides a theoretical basis for the applications of UHPC in airport pavement and presents innovative perspectives on into material and structural design of airport pavement materials for the future.

Laboratory Evaluation of Mechanical Properties and Noise Absorption in Magnetite-Enhanced Concrete for Pavement Applications

This paper aims to evaluate the effects of incorporating magnetite as an aggregate in concrete mixtures and as a partial replacement for Portland cement in standard mortar mixtures, focusing on performance and mechanical properties. Noise pollution from cement concrete pavements has become a significant concern for residents, making it a priority to implement effective measures to reduce traffic noise pollution. The primary goal of this research is to explore the relationship between mixture design variables with magnetite aggregates as a partial replacement for Portland cement in concrete pavement and the mixture's acoustic performance. Samples with 0, 10, 20, 30, 40, and 50% replacement of aggregates with magnetite sand were prepared initially. Subsequently, Portland cement was replaced with 0, 1, 2, 3.5, 5, 7.5, 10, 15, and 20% magnetite concentrate powder in standard mortar. Routine tests, such as slump, density, and flow table, were conducted on fresh concrete and mortar. Additionally, compressive strength, flexural strength, water absorption, electrical resistance, and impedance tube tests were performed on the concrete and mortar mixes. The impedance tube measurements demonstrated an increase in the sound absorption coefficient for concrete incorporating magnetite compared to the reference concrete. Among the tested concrete samples, the one containing 50% magnetite as aggregate exhibited the highest sound absorption coefficient, reaching a maximum value of 0.1 within the frequency range of 315 to 400Hz. This value was 2.5 times higher than the maximum sound absorption coefficient of the reference concrete.

Improving thermal cracking and fatigue cracking performance of hard asphalt binders with bio-renewable additives

Traditional hard asphalt, due to its low cost and excellent mechanical properties, is considered a favorable material for resisting permanent deformation under high-temperature conditions. However, its limited stress relaxation ability at medium and low temperatures significantly impairs its capacity to meet the cracking resistance requirements. To address the limitation, this study synthesized three green and sustainable bio-renewable additives derived from high oleic rapeseed oil. These additives aimed to improve the performance of hard asphalt at medium- and low-temperature conditions, thereby broadening its potential for application in green and low-carbon construction practices. Bending Beam Rheometer (BBR) tests were conducted to determine the critical low-temperature difference (ΔTc) to evaluate the thermal cracking resistance of bio-modified hard asphalt. The effects of the bio-additives on fatigue cracking resistance of hard asphalt were investigated using rheological indices, crossover frequencies, Glover-Rowe (G-R) parameters, and Linear Amplitude Sweep (LAS) tests. The results indicated that bio-additives effectively alleviated the stress in hard asphalt and reduced the asphalt’s susceptibility to thermal cracking by improving the flexibility and stress relaxation of the hard asphalt at low temperatures. Furthermore, the bio-additives substantially improved the ductility and toughness of hard asphalt at intermediate temperatures by lowering its strain sensitivity and increasing its fatigue cracking resistance. Additionally, the high oleic rapeseed oil-based derivatives notably reduced hard asphalt binder’s cracking induced by aging. Among the three bio-additives, acrylated epoxidized high oleic rapeseed oil (AEHORO) and epoxidized high oleic rapeseed oil (EHORO) were noticed to exhibit the most significant improvements in thermal cracking resistance and anti-aging properties, demonstrating superior load-bearing capacity at low temperatures. Overall, the developed bio-additives significantly improved both the thermal cracking and fatigue damage resistance of traditional hard asphalt, thus expanding its applications in pavements for various regions.

Performance Evaluation of Drying Shrinkage and Durability in Pavement Quality Concrete with Recycled Aggregate, GGBS and I-Crete

<p style="line-height:200%;text-align:justify;"><span>The study examines replacement of natural aggregates (NA) with Recycled Aggregate (RA) in Pavement Quality Concrete (PQC) M40 grade (M1) with 25%, 50%, 75% and 100% RA replacing NA in M2, M3. , M4 and M5 mixes. The compressive strength decreases with higher RA, but all mixes reach the target strength at 28 and 90 days. M5 was tested by adding Ground Granulated Blast furnace Slag (GGBS) in increments of 5% to 15% in M6, M7 and M8 to reduce the cement content. The main performance parameters include compressive strength, drying shrinkage, water penetration, Rapid Chloride Permeability Test (RCPT) at 28 and 90 days and sorptivity at 28 days. M5 reduced compressive strength but increased drying shrinkage, sorptivity, penetration depth and RCPT charge passage. Increasing the GGBS by 10% in M7 improved the strength, while increasing the GGBS by 15% in M8 decreased the strength compared to M1 and M5.</span> <span>To address strength degradation, the study incorporated 2% I-Crete along with GGBS in 5% increments from 15% to 35% in M9 to M13 mixes. M11 mix (2% I-Crete, 25% GGBS) showed better strength, reduced shrinkage and lower RCPT charge, ensuring better durability for SEM and XRD pavement applications.</span></p>

Consolidation Enhancement of Weathered Coal Gangue Utilized for Aggregate Filling of Cement Pavement in Mining Area

The large-scale, open-air storage of coal gangue often leads to oxidation and decomposition due to natural weathering, resulting in decreased strength and instability, which limits its wider application in concrete pavement. To address these issues, this paper proposed a composite consolidation treatment for weathered coal gangue (WCG), assessing its effectiveness and enhancement mechanisms through aggregate performance tests, mixture performance tests, and microscopic visualization analyses. Results indicated that the initial and post-20 dry–wet cycle crushing values of WCG were 23.96% and 47.94%, respectively, failing to meet required standards. However, applying a composite consolidation treatment using a lithium curing agent and cement paste significantly improved WCG’s robustness and stability. After 4 days of treatment, the crushing value, impact value, and Vickers hardness of WCG had reached 18.3%, 6.58%, and 113.52 kgf/mm², respectively, fully meeting the standards for aggregate filling in mini concrete pavements. Furthermore, tests demonstrated that the lithium curing agent induced the formation of hydrated calcium silicate and calcium aluminate on both the surface and interior of the WCG, enhancing its structural stability. Approximately 5–12 wt.% of the curing agent penetrates and encapsulates the WCG, strongly bonding and reinforcing its internal weak surfaces. These findings offer potential solutions and technical insights for the large-scale management of weathered coal gangue.

Agro-industrial waste utilization in air-cured alkali-activated pavement composites: Properties, micro-structural insights and life cycle impacts

This study investigates the development and performance of agro-industrial waste-based air-cured alkali-activated composites (AC) for sustainable high-strength pavement applications. The calculated amount of Na2SiO3 and NaOH were employed with water to generate alkaline activator solution. Locally sourced materials, including blast furnace slag, construction and demolition (C&D) waste, and sugarcane bagasse ash (SBA), were utilized to examine mechanical properties, micro-structural behaviour, and life cycle impacts. Optimized AC mixes containing 50% recycled aggregates (RCA) and 15% SBA demonstrated superior compressive, tensile, and flexural strength, while significantly reducing embodied energy and carbon emissions. Microstructural analysis through XRD, SEM, EDAX, and TGA confirmed the formation of stable alumino-silicate hydrate phases, contributing to enhanced superior-strength. The life cycle analysis results indicated considerable environmental benefits compared to traditional OPC pavement concretes. This research presents a sustainable solution for pavement infrastructure, aligning with circular economy principles by promoting the reduction of resource consumption and greenhouse gas emissions.

The Basic Rheological Properties of LDPE Modified Bitumen

Various polymers have widely known in its capability in enhancing rheological properties of bitumen for various pavement applications. Many polymer types have been used in studies, where the properties of the final product of the polymer modified bitumen (PMB) are different, depending on the used polymers. LDPE or Low-Density Polyethylene are one of widely studied polymers in bitumen modification that exhibit higher bitumen's viscosity, perform better in resisting deformation under heavy loads, and tend to show better integrity in high temperatures. LDPE-modified bitumen also believed to enhance elasticity, allowing a potentially better resistance to cracking due to ability to recover at low strain. Many studies also stated the improvement of LDPE-modified bitumen against thermal and mechanical stress, better adhesion to aggregates in asphalt mixtures, and various promising result for overall durability and longevity of pavement. This study explains basic rheological properties of LDPE-modified bitumen prepared by high shear mixing and specified preparing methodologies. Five variables of %modifications were used: 2%, 4%, 6%, 8% and 10% of bitumen weight. Ring and Ball softening point, Penetration test and rotating spindle viscometry were done to understand the rheological changes of the modified bitumen compared to unmodified bitumen control. For further understanding the behaviour, two types of LDPE were used: virgin LDPE and recycled LDPE. The study shows interesting noticeable differences between the two used LDPE polymers, allowing further proposed studies in this field.

Durability Investigation of Ultra-Thin Polyurethane Wearing Course for Asphalt Pavement

In this study, a wear-resistant ultra-thin wear layer was fabricated with polyurethane as an adhesive to investigate its durability for pavement applications. Its road performance was investigated based on indoor tests. First, the abrasion test was performed using a tire–pavement dynamic friction analyzer (TDFA), and the surface elevation information of the wear layer was obtained by laser profile scanning. The relationship between the anti-skid properties of the wear layer and the macro-texture was analyzed. Second, a Fourier infrared spectrometer and scanning electron microscope were employed to analyze the evolution of polyurethane aging properties in the pull-out test and accelerated ultraviolet (UV) aging test. The results showed that the mean profile depth (MPD), arithmetic mean wavelength of contour (λa), surface wear index (SBI), stage mass loss rate (σ), and total stage mass loss rate (ω) of the abrasive layer aggregate had significant multivariate quadratic polynomial relationships with the skidding performance of the abrasive layer. The tensile strength of the polyurethane ultra-thin abrasive layer decreased by only 2.59% after 16 days of UV aging, indicating a minimal effect of UV action on the aggregate and structural spalling of the polyurethane abrasive layer.

Cement-based and alkali-activated controlled low-strength materials made from cup lump rubber for use as road materials

This research explores the use of cup lump rubber (CLR), an agricultural by-product, as a component in controlled low-strength material (CLSM) for pavement applications in road construction. Two distinct CLSM mixtures were developed: one based on cement and the other on alkali activation. The study evaluated the workability, mechanical properties, and microstructures of both CLSM formulations. Key fresh properties, including slump flow, setting time, and bleeding, were analysed to assess their impact on the self-compaction process. Mechanical characteristics such as unconfined compressive strength, resilient modulus, and wave velocities were also measured. Some CLSM mixtures, both cement-based and alkali-activated, were found to meet the requirements for soil cement bases and subbases. Notably, the resilient modulus values showed significant improvement after 28 days, with certain mixtures achieving subbase-quality gravel standards. The study concludes by recommending the use of both cement-based and alkali-activated CLSMs in pavement design, highlighting their potential to enhance the field of pavement engineering.

A detailed investigation on assessing the introduction of hybrid fibres in Geopolymer composites for pavement application

ABSTRACT Geopolymer concrete (GPC) has been widely researched as an emerging sustainable construction material. As GPC possesses excellent mechanical and durability properties, it is highly recommended for the construction of rigid pavements. However, the brittle nature of GPC limits its utilisation in heavy traffic roads, reducing its fatigue life. This study aims to minimise the brittleness of Pavement quality GPC (PQGPC) by adding hybrid fibres (steel fibre + polypropylene fibre). Fresh, hardened and durability properties of hybrid fibre-reinforced pavement quality geopolymer concrete (HGPC) under ambient curing have been analysed. In addition, the experimental study also compared the flexural fatigue life of PQGPC with that of the best HGPC mix. Both fibres were added in the same % (by volume) up to a maximum dosage of 1.25% each. Results show that workability decreases with increased fibre addition, but compressive and flexural strength increases with an increment in the quantity of fibres up to 1%. It was observed that the abrasion resistance and shrinkage resistance also increase with the inclusion of hybrid fibres in HGPC. Fatigue results prove that the fatigue life of HGPC-3 (with 2% hybrid fibres addition) mix under medium and heavy loads is 40% and 28%, higher than PQGPC.

A Review of Sustainability by Utilization of Reclaimed Asphalt Pavement in Both Concrete and Pavement Application

A Review of Sustainability by Utilization of Reclaimed Asphalt Pavement in Both Concrete and Pavement Application

The influence of residual asphalt material in the mechanical behaviour of soil-RAP mixtures for use in paving

ABSTRACT The evaluation of Reclaimed Asphalt Pavement (RAP)’s suitability for pavement layers, optimises resource use, reduces environmental impact, and supports cost-effective practices. In this sense this study aimed to characterise soil-RAP mixtures to ensure they meet the quality standards required for pavement applications. The study examined two types of soil mixtures: one soil-RAP aggregates and the other soil-virgin aggregates (VAM) to understand the impact of residual asphalt binder on aggregate particles. Various mass contents (30%, 50%, 70%, and 90%) were tested alongside conventional soil-gravel mixtures with equivalent proportions and gradation of RAP and VAM. Additionally, the study investigated the effect of adding 2% cement on the performance of both recycled soil-RAP mixtures and conventional soil-gravel mixtures. The analysis includes granulometry, Atterberg Limits, MCT (Miniature, Compacted, Tropical) classification, soil chemical characterisation and microscopic images, compaction in Modified Proctor Energy, CBR, Resilient Modulus tests and stress–strain analysis. The results have revealed that the residual asphalt binder, surrounding RAP aggregates, has reduced the soil mixtures’ strength for different RAP contents. However, the study demonstrated that the addition of cement rendered the soil-RAP mixture feasible, enabling the application of the studied mixtures of RAP to constitute subbase and base layers.

Innovations in recycled construction materials: paving the way towards sustainable road infrastructure

The expansive development of infrastructure has led to increased consumption of virgin aggregates in road construction, resulting in significant environmental impacts. To address this issue, there is a pressing need for sustainable alternatives that utilize recycled materials in pavement applications. This paper presents a comprehensive review of a decade-long research program focused on the development and evaluation of sustainable pavement materials, such as recycled and waste aggregates, industrial by-products, and natural fibers. The research encompassed a wide range of innovative materials and technologies, such as geopolymer-stabilized recycled aggregates, cement-stabilized waste materials, natural additive-modified cement stabilization, and recycled aggregate-geogrid reinforcement systems. The experimental framework employed a combination of mechanical testing, durability assessment, microstructural analysis, and environmental safety evaluation to assess the performance and sustainability of these materials. The key findings demonstrated the superior mechanical properties, improved durability, and environmental suitability of the recycled materials compared to conventional virgin aggregates. The successful implementation of these sustainable solutions in real-world projects highlights their potential to reduce the environmental footprint of road infrastructure development. Furthermore, the paper discussed the practical implications of the research outcomes for pavement design and construction, as well as future research directions to further advance the field of sustainable pavement engineering. The findings of this research report can be used as guidance for researchers, practitioners, and policymakers seeking to upcycle the widespread adoption of recycled materials in road application and contribute to the development of a more sustainable and resilient transportation infrastructure.

Experimental Analysis of Noise Characteristics on Different Types of Pavements inside and outside Highway Tunnels

Aiming to reduce noise pollution and optimize the acoustic quality in highway tunnels, the noise characteristics on different types of pavements were analyzed and compared in this research, based on the on-site noise measurement in two tunnels with the free fields as a control group. Specifically, the noise characteristics include two aspects: various noise and noise time attenuation performance. Various noise includes on-board sound intensity (OBSI) noise and cabin noise. The noise time attenuation performance uses the indicator of reverberation time. Three types of pavements were measured, including dense-graded asphalt concrete (DAC) and single-layered and double-layered porous asphalt (PA) pavement. The results showed that, for the same type of pavement, compared with the free fields, the difference in OBSI noise in tunnels was within a range of less than 1 dBA; the cabin noise increased by 3.4 dBA~6.6 dBA. The noise level in tunnels was greater than that outside tunnels, and the longer tunnel exhibited higher traffic noise and worse noise time attenuation performances. For the same tunnel, PA pavement could reduce the cabin noise by 3.8 dBA~6.7 dBA. PA pavement also exhibited shorter reverberation time. The application of PA pavement could effectively improve the acoustic quality in the tunnel. This research contributes to noise pollution abatement and the improvement of the comfort and safety of drivers in tunnels.

Sustainable Geopolymer Concrete for Pavements: Performance Evaluation of Recycled Concrete Aggregates in Fly Ash-Based Mixtures

This study investigates the feasibility of incorporating recycled concrete aggregates (RCA) into fly ash-based geopolymer concrete for sustainable pavement applications. The research evaluates RCA’s physical and mechanical properties compared to virgin coarse aggregates (VCA) and assesses the performance of geopolymer concrete mixtures with up to 40% RCA replacement. Aggregate characterization revealed that RCA exhibited higher water absorption (4.39%), crushing value (20.9%), impact value (28.2%), and abrasion value (26.1%) compared to VCA, yet these values remained within acceptable limits for pavement applications. Geopolymer concrete specimens were tested for compressive strength, water absorption, abrasion resistance, and chloride ion permeability. Results indicated that increasing RCA content led to a gradual decrease in compressive strength, from 40.16 MPa to 33.52 MPa, while water absorption increased from 5.2% to 6.8%. Abrasion resistance declined as RCA content rose, and chloride ion penetrability increased from 1687 to 2196 coulombs. However, mixtures with up to 20% RCA replacement met the strength and durability criteria required for pavement construction. This study demonstrates the potential for utilizing RCA in geopolymer concrete pavements, offering a sustainable solution for waste management and resource conservation in the construction industry.

Rice husk ash blended self-consolidating concrete for application in rigid pavements: transforming agro-industrial waste into environment-friendly and sustainable material

Rice husk ash blended self-consolidating concrete for application in rigid pavements: transforming agro-industrial waste into environment-friendly and sustainable material