Road Construction Practices Research Articles

Long-term performance of porous asphalt pavement incorporating recycled plastics

Recycling plastic in asphalt pavement holds potential for environmental and economic benefits. However, its performance after prolonged exposure to heat, oxygen, sunlight, and moisture remains uncertain, casting doubt on its viability. In this study, various types of recycled plastics were incorporated into porous asphalt mixtures and exposed to long-term aging conditions. A total of 360 specimens were tested to evaluate several key properties: moisture susceptibility and rutting resistance; abrasion resistance; and indirect tensile strength and fatigue resistance. The results indicate that porous mixtures with 5 % plastic generally exhibit superior long-term performance compared to non-plastic porous mixtures, except for cracking resistance. Excessive addition of plastic (15 %) in asphalt pavement can lead to significant degradation of long-term performance. A trial section incorporating plastic in porous asphalt pavement exhibited satisfactory performance after a year of construction. These insights are pivotal in shaping policy and directing resources toward sustainable road construction practices.

More than one landslide per road kilometer – surveying and modeling mass movements along the Rishikesh–Joshimath (NH-7) highway, Uttarakhand, India

Abstract. The rapidly expanding Himalayan road network connects rural mountainous regions. However, the fragility of the landscape and poor road construction practices lead to frequent mass movements alongside roads. In this study, we investigate fully or partially road-blocking landslides along National Highway (NH-7) in Uttarakhand, India, between Rishikesh and Joshimath. Based on an inventory of >300 landslides along the ∼250 km long corridor following exceptionally high rainfall during September and October 2022, we identify the main controls on the spatial occurrence of mass-movement events. Our analysis and modeling approach conceptualizes landslides as a network-attached spatial point pattern. We evaluate different gridded rainfall products and infer the controls on landslide occurrence using Bayesian analysis of an inhomogeneous Poisson process model. Our results reveal that slope, rainfall amounts, lithology and road widening are the main controls on landslide occurrence. The individual effects of aggregated lithozones are consistent with previous assessments of landslide susceptibilities of rock types in the Himalayas. Our model spatially predicts landslide occurrences and can be adapted to other rainfall scenarios, thus having potential applications for efficiently allocating efforts for road maintenance. To this end, our results highlight the vulnerability of the Himalayan road network to landslides. Climate change and increasing exposure along this pilgrimage route will likely exacerbate landslide risk along the NH-7 in the future.

Potential reuse of fine sediment from hydroelectric dams and recycled concrete sand in road subgrades

Hydroelectric dams play a crucial role in power generation, water storage, and irrigation. However, their continuous operation has led to sediment accumulation, thereby reducing the water storage capacity and impacting the facility's life span. The aim of the current study is to assess the reuse potential of dredged fine sediment in the composition of road subgrades. Nine types of sediment from diverse hydroelectric dams are analyzed for their chemical, environmental, physical, and geotechnical properties. These sediments then were treated with quicklime and a slag-based hydraulic road binder (3% and 6%, respectively). The current investigation involves evaluating: Proctor parameters, the immediate bearing index, treatment ability, and the mechanical properties of the treated sediment. The results reveal that the properties of treated sediment differ from one mixture to another, thus, indicating that some mixtures meet the criteria outlined in the French Roadworks Guide, by virtue of their clay and organic matter contents. Moreover, the current study explores the impact of incorporating recycled concrete sand (RCS) as a granular corrector to enhance the reuse potential of the sediment in road subgrades. The current findings indicate that adding RCS significantly improves mixture properties, particularly mechanical characteristics, by reaching 1 MPa before 7 days of curing. These promising outcomes pave the way for more advanced road construction practices in ensuring environmental compliance and promoting an eco-friendly reuse of sediment.

Mechanical and Microstructural Analysis of Treated Tuff with Metakaolin Geopolymer Cement for Road Base layers Applications

Traditional road bases materials such as natural gravel and crushed stone are environmentally damaging, and there is a growing need for sustainable and eco-friendly alternatives. One such alternative is using geopolymer cement and tuff as aggregate materials. Geopolymer cement is an innovative and environmentally-friendly alternative to traditional Portland cement, and using locally-sourced tuff as an aggregate material can further reduce the environmental impact of road construction. This article discusses the importance of sustainable road construction practices, particularly in the use of eco-friendly materials for road base layers. It focuses on the treatment of tuff with alkali-activated metakaolin as the geopolymer precursor activated with a mixture of sodium hydroxide and sodium silicate. The effectiveness of treating tuff with metakaolin geopolymer cement is evaluated using several parameters, including dry density, California Bearing Ratio (CBR), shear strength, and microstructure analysis. These evaluations are performed with different NaOH dosages (8, 10, and 12 moles) to determine the optimal molarity for enhancing the material's performance.

Comparison of Compressive Strength Among 5 Different Brands of Cement Used in Construction of Road in Nepal

In Nepal, road transportation is essential but often hindered by the rapid deterioration of bituminous roads during the rainy season. To address this issue, this research focused on evaluating the strength of M20 grade concrete from five different Ordinary Portland Cement (OPC-43) brands available in Nepal: Brands A, B, C, D, and E. A series of comprehensive tests such as compressive strength tests, sieve analysis, Los Angeles Abrasion tests and Aggregate Impact Value test. The compressive strength tests revealed significant variations among the cement brands. For instance, at 7 days, the highest compressive strength observed was 28.08 N/mm² from Brand A, while the lowest was 13.10 N/mm² from Brand C. At 28 days, the highest strength recorded was 33.63 N/mm² from Brand D, and the lowest was 19.41 N/mm² from Brand C. These discrepancies highlight the need for better quality control and accurate labeling. By analyzing the performance of each cement brand, we aim to help contractors and project managers choose the best materials for building more durable reinforced concrete roads. Our findings suggest that reinforced concrete roads could be a more reliable and low-maintenance solution, especially suited for Nepal's challenging terrain and climate. We recommend further research to explore a wider range of cement brands and improve testing standards to ensure better road construction practices in Nepal.

Social impacts arising from road infrastructure projects in Sub-Saharan Africa: better management of social issues is needed in road construction, upgrading and rehabilitation

ABSTRACT Despite the use of environmental and social impact assessments for road projects, severe social impacts continue to occur. We discuss the social impacts associated with the construction, upgrading, widening and/or rehabilitation of roads in Sub-Saharan Africa. In addition to a literature review, we analysed 10 road projects in Uganda by examining project planning documents, and undertaking in-depth interviews, group interviews and field visits. While there were some benefits from these road projects, especially dust reduction where roads became sealed, the significant land acquisition necessary for these linear projects has led to physical displacement, economic displacement, and disruption to the livelihoods of local people. Other issues included: inadequate community engagement; delayed payment of compensation and inadequate compensation; gender-based violence; poor road construction practice causing community safety concerns; project-induced in-migration or influx; sexual harassment; impacts on children; and issues around sex work. The lack of local community acceptance (social licence to operate) of the projects resulted in construction delays and increased costs. For more acceptable road projects, better community engagement, improved planning and management, and adequate funding for resettlement and compensation are essential.

Enhancing Porous Asphalt Performance by Adding Waste Mask Fiber: Experimental Analysis of Stiffness, Fatigue, and Creep at Optimum Asphalt Content

Purpose: This study aims to evaluate the impact of incorporating waste mask fibers into porous asphalt mixtures, focusing on stiffness, fatigue, and creep performance at the optimum asphalt content (OAC). Theoretical Reference: The study is based on sustainable construction and materials engineering theories, emphasizing the recycling of waste materials to enhance the performance of construction materials and mitigate environmental impacts. Method: Laboratory experiments were conducted by adding waste mask fibers at varying levels (0%, 1%, 2%, and 3% by weight of asphalt) to the porous asphalt mixtures. Test specimens were designed and evaluated for stability, flow, Marshall Quotient, Voids in Mineral Aggregate (VIM), indirect tensile strength (ITS), stiffness (ITSM), fatigue, and creep performance. Results and Conclusion: The addition of 1% waste mask fibers at the OAC is recommended as it meets the criteria for stability, flow, Marshall Quotient, and VIM. The Cantabro Test showed enhanced resistance, while the ITS Test indicated increased indirect tensile strength. The ITSM Test revealed heightened stiffness of the mixture. Although fatigue testing demonstrated that the porous asphalt mixture could bear loads until collapse at a certain stress level, the creep test confirmed the mixture's resistance to permanent deformation due to traffic loads. Implications of research: The findings suggest that incorporating waste mask fibers into asphalt mixtures can improve mechanical properties and durability, offering a sustainable solution for mask waste disposal. This approach can be adopted by policymakers and engineers to enhance road construction practices while addressing environmental concerns. Originality/value: This study provides novel insights into the recycling of waste mask fibers in asphalt mixtures, demonstrating their potential to improve performance and sustainability in road construction. The research offers a pioneering approach to addressing the environmental challenges.

Enhancing soft subgrade performance with geocomposite-embedded capping layer: utilising Australian granular pavement design chart for assessing geocomposite benefits

Improving soft subgrades in road construction is essential for efficient machinery use, reducing gravel layer thickness, and enhancing pavement performance. Traditional methods like gravel replacement and chemical stabilisation are costly and harmful to the environment. Geosynthetics offer a cost-effective, eco-friendly alternative, but their full potential in Australian pavement design remains untapped due to limited research on estimating their modulus. This study addresses this gap by modeling geosynthetic-stabilised subgrades in a controlled environment and conducting plate load tests. Results show that incorporating geocomposites reduces capping layer thickness by 25% and overall granular cover by 20%. By developing a method to estimate geosynthetic-stabilised subgrade modulus and integrating it into design charts, this research aims to promote more efficient and sustainable road construction practices in Australia.

Characterization and Utilization of Recycled Aluminium Residues for Eco-Friendly Road Construction Practices

Characterization and Utilization of Recycled Aluminium Residues for Eco-Friendly Road Construction Practices

Influence of Maintenance Funds on Improve Road Steadiness with the Curva Expert Program

Sustainable road construction is instrumental in improving connectivity among regions and economies while also offering road users a diverse range of options within the traffic network. To ensure optimal road performance for users, it becomes essential to allocate adequate maintenance funds that correlate with the planned service life. This necessity originates from a profound understanding of the significant influence maintenance funds have on road steadiness. Therefore, this study aims to establish a comprehensive road steadiness model, investigating the influence of toll roads as new routes and the impact on maintenance funds. The analysis included national roads across 15 cities in Central Java Province, Indonesia, covering a distance of 759.75 km from 2018–2023. Using a quantitative approach, the study adopted the Curva Expert program to evaluate the values of road steadiness and maintenance funds. The results showed a 5.78% enhancement in road steadiness over the period from 2018 to 2023, underscoring the positive impact of sustainable road construction practices and the allocation of adequate maintenance funds. The establishment of relationship between road steadiness and maintenance funds was established through a regression value of R2=0.94. This statistical correlation is represented by the equation y= 90.521 + 0.022x, providing a quantitative understanding of how maintenance funds influence road steadiness. The insights obtained from the outcomes of road steadiness modeling reiterate the significance of investing in additional routes and ensuring sufficient maintenance funds to improve performance. Doi: 10.28991/CEJ-2024-010-02-014 Full Text: PDF

Enhancing high-content recycled asphalt pavement regeneration: A laboratory separation and treatment approach

The escalating costs of aggregates and stringent sustainable development policies have emphasized the significance of effective high-content recycled asphalt pavement (RAP) regeneration technology. This study aims to present a novel laboratory separation and treatment approach for RAP materials, ensuring optimal performance of high-content RAP recycled asphalt mixtures. The proposed method is compared against factory-separated RAP materials in terms of agglomeration evaluation and mixture performance comparison. High- and low-temperature performance of the recycled asphalt mixture were evaluated through wheel tracking and trabecular bending tests. Furthermore, the moisture sensitivity of the recycled mixture was studied through immersion Marshall and freeze-thaw splitting tests. The uniformity and fusion between aggregates and asphalt in the recycled asphalt mixtures were meticulously analyzed using advanced techniques such as Scanning Electron Microscope and industrial Computed Tomography scans. The laboratory separation method encompasses flexible separation for 5–10 mm RAP materials and rigid separation for 10–20 mm RAP materials. Notably, the laboratory separation methods proved more effective in removing aged asphalt from the surface of 10–20 mm RAP materials compared to factory separation, thereby enhancing the adhesion between aggregates and asphalt and ensuring a more uniform recycled mixture. Although the dynamic stability of recycled asphalt mixture was reduced using laboratory separation, it still meets the requirements of relevant specifications. Moreover, the low-temperature maximum flexural tensile strain of the recycled asphalt mixture increased by 16%, with the residual stability and tensile strength ratio rising by 1.33% and 2.69%, respectively. Compared with the factory separation method, the laboratory separation method reduces the porosity percentage of the recycled asphalt mixture cross-section by 3.47%. Overall, the laboratory separation method for RAP materials provides valuable insights for enhancing the factory processing of RAP materials, contributing to the successful application of high RAP content regeneration technology in the pursuit of sustainable and cost-effective road construction practices.

An investigation of the efficacy of nanoemulsions as alternative treatment for a marginal quality pavement material

Stabilisation of road materials that do not meet specified requirements is a common practice in road construction. Cement and lime are among the most commonly used products for stabilisation. However, these products pose challenges in particular conditions, including rigidity and proneness to cracking, incompatibility with certain materials types and susceptibility to particular environmental conditions. In this regard, alternatives have been considered and nanotechnology-based materials have emerged as a viable option. For this study, the efficacy of Nano-Modified Emulsion (NME) for stabilisation of gravel material was investigated. The gravel material, stabilised with up to 1.5% NME was evaluated in the laboratory for mechanical strength characteristics and resistance to moisture damage. Results obtained for Static Triaxial Tests (STT) show that the NME improves the cohesion of the material by up to 54% but has no significant effect on the friction angle. Significant improvements are also noted in the results for California Bearing Ratio (CBR), Unconfined Compression Strength (UCS) and Indirect Tensile Strength (ITS) tests. The results also show that NME stabilisation improves the gravel material's resistance to moisture damage. Further investigations are recommended for repeated load triaxial tests, field trials, environmental risks and life cycle costs.

ОСНОВНІ ПРОБЛЕМИ ІНЖЕНЕРНО-ПЛАНУВАЛЬНИХ РІШЕНЬ ТРАНСПОРТНИХ РОЗВ’ЯЗОК ТИПУ «РОЗІРВАНЕ КІЛЬЦЕ» ТА ШЛЯХИ ЇХ УСУНЕННЯ

Introduction. Interchange designs that provide specific benefits to road users will always be of interest. It is extremely interesting a type of interchange in the same level named in literary sources as a «hamburger roundabout» or «throughabout». Usually, two separate lanes run through the extended roundabout, crossing each other inside the interchange. Such intersections can be regulated by both road signs and traffic lights, depending on their size and the intensity of incoming traffic flows. Problem Statement. The analysis of the designs of the intersection at one level by the type of throughabout is insufficiently presented both in the normative documentation for the design of highways and in modern scientific periodicals. However, this type of intersection refers to alternative junctions used in road construction practice in European countries. Thus, an urgent task is to evaluate the operational efficiency indicators and surrogate traffic safety indicators of the throughabout, which can later serve as a basis for making decisions about the need to construct this type of intersection. Purpose – to identify the main problems of the interchange by the type of throughabout based on the analysis of traffic efficiency and safety indicators, carried out by the method of traffic microsimulation.

Recycled keratin biofiber-asphalt composites: Investigations on compatibility and performance

The study explored the potential of keratin biofiber, derived from waste human hair, in augmenting the engineering qualities of asphalt. Keratin biofiber (KBF) was obtained through an alkali degreasing process on waste hair. Subsequent to this, keratin biofiber-asphalt (KBF-A) composites were formed by mixing KBF with base asphalt. Advanced methods, including scanning electron microscopy, energy-dispersive spectrometry, thermogravimetric analysis, and Fourier transform infrared spectroscopy were employed to ascertain that the degreasing process enhanced the compatibility between the biofiber and asphalt by altering the biofiber's surface structure. The Response Surface Methodology (RSM) was applied to pinpoint the optimal parameters for formulating KBF-A. The results demonstrated that the integration of KBF fortified the asphalt's resistance to elevated temperatures, albeit with a minor compromise in its ductility at lower temperatures. The optimal KBF-A composite contained 0.348% KBF with a fiber length of 6.618 mm. Road performance assessments revealed that KBF bolstered the asphalt mixture's defense against high-temperature deformation, amplified its flexural strength at lower temperatures, and elevated its resistance to water erosion. These insights underscore the potential advantages of repurposing discarded human hair for engineering purposes and suggest its prospective value in advancing eco-friendly road construction practices in the future.

The Use of Waste Polymers in Asphalt Mixtures: Bibliometric Analysis and Systematic Review

Asphalt is widely employed in road construction due to its durability and ability to withstand heavy traffic. However, the disposal of waste polymers has emerged as a significant environmental concern. Recently, researchers have used polymer waste to modify asphalt pavements as a new approach. This approach aims to improve pavement performance and address the environmental concerns of polymer waste. Researchers have demonstrated that incorporating polymeric waste into asphalt mixtures can lead to performance improvements in asphalt pavements, particularly in mitigating common distresses including permanent deformation and thermal and fatigue cracking. The current comprehensive review aims to summarize the recent knowledge on the usage of waste polymers in asphalt mixtures, encompassing their impact on performance properties and mixture design. The review also addresses different types of waste polymers, their potential benefits, challenges, and future research directions. By analyzing various studies, this review offers insights into the feasibility, effectiveness, and limitations of incorporating waste polymers into asphalt mixtures. Ultimately, this contributes to the advancement of sustainable and environmentally friendly road construction practices.

Feasibility of Pellet Material Incorporating Anti-Stripping Emulsifier and Slaked Lime for Pothole Restoration

Climate change has caused a surge in abnormal weather patterns, leading to a rise in cracks, plastic deformation, and pothole damage on road surfaces. In order to fabricate a ready-mix admixture of warm asphalt mixture (WMA) for pothole restoration, this study aimed to develop a neutralized anti-stripping material in pellet form by extruding a combination of slaked lime and a liquid emulsifier additive. Slaked lime (1% by weight of aggregate) was chosen for its ability to enhance moisture resistance, while a liquid emulsifier (wax + vegetable oil + surfactant + water) was added to create a pellet-type stripping inhibitor for WMA. After successfully fabricating the pellet admixture, this study evaluated the performance of two asphalt mixtures: conventional Slaked Lime Hot Mix Asphalt (LHMA) and the Pellet-Type Anti-Stripping Warm Mix Asphalt (PWMA). Several compatibility tests were conducted to evaluate the quality of the developed material. The results showed that the fatigue resistance of the developed material (PWMA) improved by over 20%, indicating an extended fatigue life for the pavement. The LHMA and PWMA met the quality standard for asphalt mixtures, with a TSR value of approximately 83%. Both mixtures demonstrated improved rutting resistance compared to HMA. The PWMA required 16,500 cycles, while the LHMA required 19,650 cycles to reach a settlement of 20 mm, indicating better moisture resistance than the control mix (13,481 cycles). The modified mixture performed properly in the Cantabro test, with loss rates below 20%, indicating their ability to retain their aggregate structure. The PWMA also showed superior resistance to plastic deformation, with a 12.5% lower phase angle (35°) at a reduced frequency of 10−3. In general, the application of PWMA not only prolongs the pavement lifespan but also reduces the production temperature by over 20 °C, leading to lower emissions and energy consumption. This makes it an environmentally friendly option for pavement applications and contributes to sustainable road construction practices.

Examining green road construction components: the case of Ghana

PurposeThe adoption of green construction concepts in road infrastructure projects is an opportunity to minimise the carbon footprint while boosting the built environment's capacity to promote sustainability. Consequently, this study examines the components of green road construction practices in developing countries such as Ghana.Design/methodology/approachUsing a quantitative research method, four hypothesised constructs identified from the review of relevant literature were tested. The views of 144 quantity surveyors, civil engineers and project managers within Ghana's three road agencies were elicited using a structured close-ended questionnaire. A confirmatory factor analysis (CFA) based on the structural equation model (SEM) was adopted in analysing the data obtained.FindingsThe study's results reveal that the identified components: sustainable design, materials and resources, stormwater management and energy efficiency, significantly influence green road construction.Practical implicationsIt reveals the critical elements of sustainable road design and construction, aiding organisations, construction companies and legislators in making informed choices on road design and construction.Originality/valueResults from this study provide empirical evidence lacking in the literature about the main components of green road construction.

Low-Carbon Road Reconstruction Design —— Empirical Research Based on Road Cost Management Software

Driven By the Low Carbon Policy, low-carbon road infrastructure construction is greatly concerned. The lack of standardized quantification of energy consumption and carbon emissions limits the universality of Low Carbon road construction practice. Based on the national road cost management software and China's life cycle core database, the standardized quantification method of energy consumption and carbon emissions is established. Empirical project data are used to check the Effectiveness of the method. The method is to screen out the design measure with better energy conservation and lower carbon emission.

The effect comparative evaluation of energy-saving additives on the bitumen properties

Energy-saving additives used in the Uzbekistan road construction practice are considered. Based on experimental data, the influence of the considered energy-saving additives on the standard, adhesive and rheological properties of petroleum road viscous bitumen has been established.

Subgrade and Pavement Design Strategies for Different Road Settlement Sections

The quality of road engineering construction largely determines the road operation safety and driving comfort. However, in road engineering construction, the settlement of subgrade and pavement has always been an insurmountable problem. Therefore, in road construction practice, targeted treatment should be carried out for the sections prone to settlement, and subgrade and pavement design strategies for these settlement sections should be carried out, so as to reduce the risk of settlement and ensure the improvement of road engineering quality and safety.