Porous Asphalt Research Articles (Page 1)

ABSTRACT Flooding, a major global climate hazard, increasingly threatens urban and low-income regions due to intensified rainfall from climate change. This study focuses on the Quad Cities – Davenport, Iowa; Bettendorf, Iowa; Moline, Illinois; and Rock Island, Illinois – to assess evolving flood risks and the effectiveness of nature-based solutions (NbS). Using CMIP6 climate models, 26 models were statistically downscaled with bicubic spline interpolation and bias corrected using empirical quantile mapping (EQM). MIROC6 was selected for its superior performance (RMSE ~14%, NSE ~0.68) when compared with US Geological Survey (USGS) raingage data. Downscaled precipitation data were ingested into SWMM+HECRAS to simulate runoff and flooding. Results reveal that NbS such as infiltration trenches, permeable pavements, and rooftop disconnections can reduce runoff by up to 37% in Rock Island and 14–30% in Davenport and Bettendorf, lowering peak runoff by 19% during extreme events. The findings guide climate-resilient urban planning and sustainable stormwater management in the face of future climate variability.

Assessing ecological and health risks of PAH compounds in Anzali Wetland: A weight of evidence perspective.

Mitigation urban heat island by using porous and permeable block pavement

Effects of clogging on void characteristics and sound absorption properties of porous asphalt pavements

Progress in research on the mechanisms of clogging behavior and its influencing factors in porous asphalt pavements

Aging gradient and aging acceleration effect on asphalt and porous asphalt mixture coupling thermal oxidation, ultraviolet radiation and water

Performance evaluation of reclaimed porous asphalt mixtures based on different mixture design methods: Meso-structural characteristics and macro-pavement properties

Evaluating Tire-pavement Noise Reduction of Porous Asphalt Using Close Proximity Tests: Comparative Performance and Long-Term Effectiveness

Evaluating permeable pavements' impact on the thermal environment in street canyons through outdoor experiments under hot and humid background climate

Determining the risk of slipping on level ice using winter footwear with varied maximum achievable angle slip-resistance performance.

In winter, some roads face the problems of severe rain accumulation and ice formation, which pose major risks to traffic safety and result in substantial economic losses. With the development of hydrophobic materials, hydrophobic coatings have gradually gained attention as a novel anti-icing technology. In this study, utilizing vinyl triethoxysilane (VTES) as the monomer and benzoyl peroxide (BPO) as the initiator, a hydrophobic anti-icing coating for highway pavements was prepared through the free radical polymerization method. Through designing the icing rate test and ice–pavement interface adhesion strength test, combining the contact angle test technology, wet wheel abrasion test, and pendulum friction coefficient test, the anti-icing performance, durability, and skid resistance performance of the hydrophobic anti-icing coating under the three types of mixtures of asphalt concrete (AC-13), Portland cement concrete (PCC), and porous asphalt concrete (PAC-13) were evaluated. The results indicate that when the surface layer of the pavement was sprayed with anti-icing coating, the water was dispersed in a semi-spherical shape and easily rolled off the road surface. Compared to uncoated substrates, the anti-icing coating reduced the icing rate on the surface by approximately 25%. Comparing with the uncoated pavements mixtures, for AC-13, PCC, and PAC-13 pavements, the ice–pavement interface adhesion strength after the application of hydrophobic anti-icing coating reduced by 30%, 79% and 34%, respectively. Both cement pavements and asphalt pavements, after the application of hydrophobic anti-icing coating, expressed hydrophobic properties (contact angle of 131.3° and 107.6°, respectively). After wet wheel abrasion tests, the skid resistance performance of pavement surfaces coated with the hydrophobic anti-icing coating met the specification requirements. This study has great significance for the promotion and application of hydrophobic anti-icing technology on highway pavements.

With the rapid pace of urbanization, the Urban Heat Island (UHI) effect has emerged as a significant obstacle to sustainable urban living, characterized by elevated temperatures in cities relative to surrounding rural areas. This article explores the intricate mechanisms driving UHI development, emphasizing key contributors such as the reduction of green spaces, heat-retaining construction materials, compact city layouts, and anthropogenic heat emissions. Meteorological factors further compound UHI intensity, underlining its multifaceted nature. The consequences are far-reaching ranging from increased energy demands and diminished air quality to elevated greenhouse gas emissions and negative impacts on public health and thermal comfort. Climate change exacerbates these effects by altering local weather dynamics and intensifying heat stress. A comprehensive assessment of detection techniques is provided, alongside a diverse set of mitigation approaches. These include nature-based interventions such as green roofs, vertical gardens, urban forestry, and blue infrastructure, as well as technological innovations like reflective roofs and permeable pavements. The article also evaluates the complex role of solar panels, which can both alleviate and contribute to heat accumulation in urban settings. This work contributes to the creation of heat-resilient cities and promotes a shift from concrete-dominated landscapes toward cooler, greener, and more sustainable urban environments.

Due to the increasing volume of traffic on the world's highways, researchers have been searching for new composite techniques and methods to develop durable and cost-effective pavement structures. The semi-rigid pavement is a composite pavement consisting of a porous asphalt mix with air voids between 25 and 30% and a high-fluidity cementitious grout. In this study, different cementitious grout mixes were prepared. Then a porous asphalt mix with almost 30% air void content was designed. After evaluating the workability, mechanical strength, and volume stability of the prepared grout mixes, the most suitable mix is proposed to fill the voids in the porous asphalt mix. Finally, the prepared semi-rigid pavement specimens were subjected to various tests to evaluate the performance characteristics of the designed pavement. The research concludes that the grout mixture ratio proposed in this study has good grouting ability and the semi-rigid pavement has superior performance characteristics.

Frequent hydrometeorological variations have increased the frequency of flooding, posing major risks to infrastructure and public safety. Fuzzy graph theory relies on fundamental concepts such as synchronising and graph domination problems, which have enormous applications in everyday life. In this study, we introduce a novel optimization framework that integrates machine learning with Bipolar Intuitionistic Fuzzy Graphs (BIFG) to optimize stormwater management through permeable pavement systems in the smart cities of Thoothukudi district, India. Bipolar Intuitionistic Fuzzy Graph based Machine Learning Optimization (BIFG-MLO) is used to characterise the ambiguous interactions between metropolitan zones affected by heavy rains, using both positive and negative membership values to indicate drainage effectiveness and waterlogging intensity. Graph dominant concepts and efficient edge detection are used to identify key zones that require infrastructure improvement. Using predictive analytics and a multi-criteria optimization method that ranks smart cities based on dominance data, permeable pavement installation can be prioritised. The results indicate that P&T Colony and Kovilpatti are the most vulnerable cities, making them exemplary choices for implementing permeable pavement. Based on performance evaluation parameters such as accuracy, precision, recall, and F1 score, the proposed model outperforms traditional methods in forecasting flood-prone areas. To improve waterlogging prediction and strategically install permeable pavement systems in Thoothukudi, India’s smart city efforts, this study introduces a hybrid optimization framework that employs Bipolar Intuitionistic Fuzzy Graph with Machine Learning Optimization (BIFG-MLO). This framework offers a scalable decision-support system for sustainable urban development in flood-prone locations.

Current understanding of the load-transfer mechanism in the skeletal contact state of asphalt mixtures and its influence on macroscopic mechanical properties remains insufficient. This knowledge gap leads to difficulties in accurately predicting the performance of designed mixtures, thereby restricting the service life of asphalt pavements and the sustainable development of road engineering. This study investigated the skeletal contact characteristics, coarse aggregate movement, and crack propagation of three asphalt mixture types—Stone Mastic Asphalt (SMA), Asphalt Concrete (AC), and Open-Graded Friction Course (OGFC)—under loading. The methodology incorporated Computed Tomography (CT) technology, a Voronoi diagram-based skeletal contact evaluation method, and discrete element numerical simulation. The research aimed to elucidate the influence mechanisms of different skeletal structures on macroscopic performance and to validate the efficacy of the skeletal contact evaluation method. The findings revealed that under splitting load, the tensile stress contact force chains within the asphalt mixture’s skeleton were predominantly distributed along both sides of the specimen’s central axis. For all three gradations, compressive stress contact force chains (points) accounted for over 65% of the total, indicating that the asphalt mixture skeleton primarily bore and transmitted compressive stresses. The interlocking structure formed by coarse aggregates significantly enhanced the stability of the asphalt mixture skeleton, reduced its displacement under load, and improved the mixture’s resistance to cracking. In the three gradations, shear stress-induced cracks outnumbered those caused by tensile stress, with shear stress cracks accounting for over 55% of the total cracks. This suggests that under splitting load, cracks resulting from shear failure were more prevalent than those from tensile failure. SMA-20 demonstrated the best crack resistance, followed by AC-20, while OGFC-20 performed the poorest. These conclusions are consistent with the results of the Voronoi diagram-based skeletal contact evaluation, confirming the correlation between the contact conditions of the asphalt mixture skeleton and its mechanical performance. Specifically, inadequate skeletal contact leads to a significant deterioration in mechanical properties. The research results elucidate the influence of skeletal contact characteristics with different gradations on both mesoscopic features and macroscopic mechanical behavior, providing a crucial basis for optimizing asphalt mixture design.

Semi-flexible pavement (SFP), a hybrid pavement system that combines open-graded asphalt with cementitious grout, offers enhanced durability, load-bearing capacity, and resistance to rutting compared to conventional pavement systems. However, the environmental impact of cement usage in grout formulations remains a significant concern due to its high carbon footprint. This study explores the feasibility of partially replacing ordinary Portland cement with industrial by-products, fly ash (FA) and silica fume (SF), in cement grouts for SFP applications. Grout mixtures with 5% and 10% replacements of FA and SF were prepared and evaluated for flowability, compressive strength (at 1, 7, and 28 days), and flexural strength (at 28 days). The study found that fly ash (FA) improves grout flow and long-term compressive strength, with 10% FA achieving a 16% increase at 28 days. Silica fume (SF) enhances both early and overall strength but reduces flowability at higher doses. Both additives improved flexural strength, with 5% FA showing a 28% increase over the target. Based on optimal flow (11–16 seconds) and compressive strength (60 MPa), the best performance was observed with 10% FA and 5% SF. These results suggest that FA and SF can serve as effective and sustainable partial replacements for cement, maintaining or enhancing mechanical performance while lowering environmental impact. This makes them suitable for use in semi-flexible pavement (SFP) applications, contributing to both durability and sustainability goals.

In the context of climate change and urban expansion, understanding unsaturated soil behavior is critical for designing resilient infrastructure. Soil moisture retention influences stormwater management, structural performance, and the effectiveness of green infrastructure. This study focuses on the influence of soil density and water content on soil-water characteristic curve (SWCC) and soil pore-size distribution. Engineered soil from Astana, Kazakhstan, was tested under varying compaction conditions: at optimum water content (OWC), wet of optimum, and dry of optimum. SWCCs were measured using Tempe cell (0–100 kPa) and WP4C (100–300 MPa). Pore-size distributions (PSD) were derived using the Fredlund and Xing equation and analyzed with scanning electron microscopy (SEM), while mineral content was determined via X-ray diffraction (XRD). Results showed that soil compacted at OWC and dry of optimum exhibited bimodal SWCCs, while wet-compacted soil showed unimodal behavior. Increased dry density resulted in reduced air entry value (AEV) and water content, while lower density led to larger dominant pore sizes and higher matric suction. These findings offer practical insights into sustainable urban living. Understanding SWCC behavior supports the design of climate-adaptive infrastructure, such as bioretention systems, permeable pavements, and vegetated swales. Optimizing soil compaction can enhance water retention and reduce flood risk, particularly in semi-arid, climate-sensitive regions like Astana. Integrating these soil mechanics principles into urban planning contributes to long-term resilience and more sustainable city development.

Performance-oriented mix design and experimental study on functional and durable porous epoxy asphalt mixtures in tunnels

Rheological Properties of Polyurethane-Modified Asphalt and Its Effect on the Performance of Porous Asphalt Mixes

Influence of aggregate gradation on clogging and permeability in porous asphalt mixtures