Search Results (79)

This study investigated the noise reduction performance of porous asphalt concrete (PAC) pavement under tire–pavement coupling conditions, addressing the limitations of field measurements and laboratory testing. First, tire excitation amplitude parameters were determined based on vibrational contact operational scenarios. Then, finite element simulations were conducted to systematically analyzing the tire–pavement coupling noise characteristics of PAC pavement. The results indicate that PAC pavement effectively reduces the air pumping noise due to its highly porous internal structure, leading to significant noise attenuation. Furthermore, the study examined the key factors influencing the tire–pavement coupling noise in PAC pavement. When maintaining constant vehicle parameters (300 kg load, 60 km/h speed), pavement thickness became the critical noise-control variable, achieving minimum vibration at 6 cm surface layer thickness. Additionally, tire tread depth (5–17 mm) and mold release angle (0–30°) had a more pronounced impact on the air pumping noise compared to groove width (20–60 mm). Increasing the mold release angle and reducing tread depth effectively mitigated the air pumping noise. However, the tire–pavement coupling noise in PAC pavement increased considerably with increasing vehicle speed and load. Particularly, as the speed increased from 30 km/h to 60 km/h, the growth of the air pumping noise was most pronounced, revealing an acoustic transition of tire–pavement coupling noise from vibration-dominated to air-pumping-dominated mechanisms. Full article

The construction industry significantly contributes to global sustainability challenges, producing 30–40 percent of global carbon dioxide emissions and consuming large amounts of natural resources. Pervious concrete has emerged as a sustainable alternative to conventional pavements due to its ability to promote stormwater infiltration and groundwater recharge. However, the absence of fine aggregates creates a highly porous structure that results in reduced compressive strength, limiting its broader structural use. Determining compressive strength traditionally requires destructive laboratory testing of concrete specimens, which demands considerable material, energy, and curing time, often up to 28 days—before results can be obtained. This makes iterative mix design and optimization both slow and resource intensive. To address this practical limitation, this study applies Machine Learning (ML) as a rapid, preliminary estimation tool capable of providing early predictions of compressive strength based on mix composition and curing parameters. Rather than replacing laboratory testing, the developed ML models serve as supportive decision-making tools, enabling engineers to assess potential strength outcomes before casting and curing physical specimens. This can reduce the number of trial batches produced, lower material consumption, and minimize the environmental footprint associated with repeated destructive testing. Multiple ML algorithms were trained and evaluated using data from existing literature and validated through laboratory testing. The results indicate that ML can provide reliable preliminary strength estimates, offering a faster and more resource-efficient approach to guiding mix design adjustments. By reducing the reliance on repeated 28-day test cycles, the integration of ML into previous concrete research supports more sustainable, cost-effective, and time-efficient material development practices. Full article

Porous concrete is widely recognized as an eco-friendly pavement material; however, existing studies mainly focus on its use as a base course, and systematic investigations on porous concrete specifically designed for heavy-traffic pavements and multifunctional surface performance remain limited. In this study, a novel multifunctional porous concrete with integrated noise reduction and drainage performance (PCNRD) was developed as a top-layer pavement material, addressing the performance gap in current applications. A comprehensive evaluation of the surface properties of porous concrete was performed based on tests of the sound absorption, void ratio, permeability, and wear resistance. The results demonstrate that the porous concrete exhibits excellent sound absorption (sound absorption coefficient 0.22–0.35) and high permeability (permeability coefficient 0.63–1.13 cm/s), and superior abrasion resistance (abrasion loss ≤ 20%) within an optimized porosity range of 17–23%. Furthermore, an optimized pavement thickness (8–10 cm) was proposed, and functional correlations among key surface performance indicators were revealed for the first time. Based on a uniform experimental design, four key mix parameters (water–cement ratio, cement content, silica fume content, and cement strength grade) were examined using strength and effective porosity as dual control indices, leading to the development of a novel mix design method tailored for PCNRD. This study not only fills the technical gap in high-performance porous concrete for heavy-traffic pavement surfaces but also provides a practical scientific framework for its broader engineering application. Full article

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. Full article

This study investigates the permeability performance and engineering performance of porous asphalt concrete (PAC) mixtures. PAC-10 and PAC-13 mixture specimens with various porosities were prepared. The relationships among porosity, effective porosity, and effective porosity proportion were analyzed, and the pavement engineering performance was evaluated. Moreover, the effects of nominal maximum aggregate size (NMAS) and porosity characteristics on the permeability coefficient were also examined. The results indicate that both the effective porosity and the effective porosity proportion increase with total porosity for both the PAC-10 and PAC-13 mixtures. PAC-13 consistently exhibits a higher effective porosity than PAC-10, suggesting enhanced drainage performance. The designed PAC mixtures satisfy the requirements of high-temperature stability and moisture resistance for asphalt pavements, while the large porosity is contradictory with high-temperature stability and moisture resistance. Additionally, the permeability coefficient significantly increases with larger NMAS, and a strong linear correlation is observed between permeability and both total and effective porosity, where the coefficient of determination (R²) is larger than 0.9. These findings demonstrate that porosity parameters can serve as reliable indicators for assessing the permeability performance of PAC mixtures with different gradations. Full article

In order to investigate the influence of different tire textures, pavement types, and vehicle parameters on the tire/road noise level and its spectrum characteristics, 19 kinds of asphalt pavement main structures of RIOHTrack full-scale test track were tested by the close-proximity trailer (CPXT) tire/road noise detection method. Considering investigated parameters such as tire texture, vehicle speed, and trailer axle weight, and relying on multi-functional road condition rapid detection vehicle and laboratory tests to collect a variety of road surface information and material parameters, a multiple-linear-regression model of tire/road surface noise level of RIOHTrack (Research Institute of Highway Full-scale Test Track) asphalt pavement was constructed. Finally, the causes of noise level differences among different influencing factors were further analyzed through spectrum characteristics. The results show that vehicle speed is the most important factor affecting tire/road noise. The noise level of different tires varies due to different textures, but the noise level among different trailer axle weights is roughly the same. Vehicle speed (v), FWD center deflection (D₀), surface asphalt mixture air voids (VV), sensor-measured texture depth (SMTD) and international roughness index (IRI) were selected to establish the noise prediction models of different tire textures. Noise spectrum analysis shows that the spectrum of different vehicle speeds is significantly wide in the full frequency range, and the spectrum variation of differently textured tires is mainly concentrated in a certain range of the peak frequency. The noise spectrum curve of porous asphalt concrete (PAC13) is significantly lower than that of other asphalt mixtures in the full frequency range above 800Hz, indicating a greater noise reduction effect. Full article

To avoid cumbersome casting procedures in the production of pervious concrete, a new type of casting method through coating cementitious paste onto the preplaced aggregate skeleton is developed. To optimize the key performances and reveal their governing mechanism, aggregate skeleton–cementitious paste-coating pervious concrete (ACPC) mixes with different porosity, water/cement (w/c) ratio and sand ratio were produced and had their permeability and strength tested. This study demonstrated that it is successful to produce pervious concrete by the novel casting method. Vibration of aggregate skeleton and high w/c ratio should not be adopted to avoid the formation of a layer of hardened paste at the bottom of the mix to block the vertical passage of water. In contrast to conventional concrete, a higher w/c ratio (from 0.23 to 0.34) generally resulted in a higher strength (from 3.77 to 8.71 MPa) of ACPC. A small amount of sand increased both the permeability and strength through the balling bearing effect and filling effect, respectively. Both the optimum sand ratio to achieve the highest vertical permeability and strength were found to be 0.05, which offered this porous structure concurrently satisfactory permeability (permeability coefficient higher than grade K2) and acceptable strength (compressive strength higher than 5 MPa). Key influencing factors of permeability and strength of ACPC were analyzed. This study can advance the technology of casting concrete and the production of pervious concrete as road pavement in the construction of “sponge city”. Full article

Urban waterlogging due to sudden rainfall leads to critical issues. This study aims to develop sustainable porous asphalt pavement by incorporating different proportions of recycled coarse aggregate. Recycled coarse aggregate from waste laboratory-tested concrete in 19, 12.5, and 9.5 mm sizes was prepared for a porous asphalt mix series (Mix-Types 1-9). The study showed that optimal aggregate ratios performed well in porous asphalt mixes. Mix-Type-3 with the aggregate ratio of 19:12.5:9.5 mm (1:1:0.5) achieved an optimal stability of 8.88 kN at the minimum flow rate. The movement of water flow results revealed that permeability decreases with time. The Mix-Type-3 permeability reductions were found to be 16.75% and 30.14% at 6 and 12 months, compared to the permeability of fresh mixes. The study results revealed that the Mix-Type-3 retained the highest stability level, and the permeability fell within the standard values. Hence, it is concluded that Mix-Type-3 balances in all parameters and is a viable choice for effective and sustainable urban water management. Full article

The use of porous concrete in various infrastructure applications such as pavements, infiltration beds, and low-volume load areas is increasingly encouraged due to its environmental benefits. The performance of porous concrete is strongly influenced by its pore structure and overall porosity. Researchers have employed multiple methodologies to characterise pore size and distribution, and to assess their effects on permeability, hydraulic conductivity, and compressive strength. This review investigates several pore measurement techniques aimed at improving both the hydraulic and mechanical performance of porous concrete. Among these, image analysis emerges as the most accurate method for assessing porosity distribution, offering higher resolution and fewer limitations compared to traditional techniques. Despite these advancements, a debate remains regarding the relative importance of effective porosity versus total porosity. This work comprehensively evaluates and synthesises existing methods for pore structure analysis, thereby enhancing our understanding of how porosity influences concrete behaviour. The findings indicate that effective porosity alone is insufficient to predict hydraulic conductivity, whereas total porosity has a considerable effect on compressive strength. This insight can be used to optimise the balance between strength and permeability in porous concrete, supporting its broader implementation as a sustainable construction material. Full article

Temperature variations have a significant impact on the performance and durability of rigid (concrete) pavement. As concrete is subjected to daily and seasonal temperature changes, it experiences thermal expansion and contraction. These movements, if not properly managed, can lead to cracking, joint deterioration, and loss of structural integrity. The pavement system is adversely affected by intense heat and significant flooding. This study aims to analyze the impact of several parameters on the performance of rigid pavement under typical, thermal, and flooding situations. This study investigates the properties of concrete and the dimensional design of rigid pavement with FEACONS IV software to assess their impact on the performance of concrete pavement during thermal and flooding conditions. The main conclusions of this study derived from the FEACONS IV analysis are as follows. Rigid pavement can enhance load-carrying capacity due to a lower elastic modulus, adequate flexural strength, and aggregates with a lower coefficient of thermal expansion. Increased thickness of concrete slabs and shorter slab lengths assist in minimizing load- and temperature-induced stresses. The increase in the subgrade modulus reaction value during flooding conditions improves pavement strength. However, in higher thermal conditions, a higher subgrade reaction modulus can increase the stress induced by temperature and load. Rigid pavement using porous limestone aggregate exhibits a reduced elastic modulus and coefficient of thermal expansion, suggesting higher resilience compared to rigid pavement composed of river gravel or granite. The findings suggest that higher thermal conditions will cause pavement damage. Agencies need to account for higher temperatures while designing and maintaining pavement. Flooding saturates the concrete pavement and subgrade layer, adversely affecting its performance over time. Full article

In cold regions, the overlay effect often leads to pavement and subgrade distresses, severely compromising the functionality of roads and infrastructure. To address this issue, this study proposes a solution involving permeable pavements and roadbed structures. However, the application of permeable pavement materials in cold regions remains a significant challenge. Building on previous research, this paper introduces a novel pavement material with exceptional mechanical and temperature performance: terminal carboxylated nitrile rubber-modified epoxy asphalt. Specifically, the mechanical properties, viscosity, high-temperature rutting resistance, low-temperature cracking resistance, and modification mechanisms of five terminal carboxylated nitrile rubber-modified epoxy asphalt mixtures with varying terminal carboxylated nitrile rubber contents were investigated. Additionally, the high-temperature, low-temperature, and water stability properties of three types of porous asphalt concrete were compared. The results demonstrate that the incorporation of terminal carboxylated nitrile rubber significantly enhances the mechanical properties and low-temperature cracking resistance of the asphalt without altering the curing time. Although the high-temperature rutting resistance of the asphalt itself decreases, the high-temperature, low-temperature, and water stability properties of the porous asphalt concrete are improved. This improvement is attributed to the chemical reaction between terminal carboxylated nitrile rubber and epoxy resin, which generates a prepolymer containing new substances and forms a stable sea–island structure. This structure promotes a more homogeneous distribution of the asphalt matrix, thereby increasing the cohesive strength and toughness of the asphalt. Full article

The substantial voids of porous pavement materials permit light and exhaust pollutants to infiltrate to a considerable depth. Consequently, utilizing porous mixtures as carriers for photocatalytic materials enables greater exposure to an environment conducive to the exhaust degradation reaction. This study employed porous asphalt mixtures and porous cement concrete as carriers for photocatalytic pavements. Various amounts of TiO₂ were incorporated as photocatalysts to produce eco-friendly pavement materials with exhaust degradation capability. Based on a self-developed apparatus and methodology, its exhaust degradation performance was evaluated under different preparation conditions and pavement structures. The influences of void ratio, photocatalyst dosage, pavement type, and pavement thickness on the exhaust degradation function were examined. The degradation rates of NO and CO among the four monitored pollutants were observed to follow a three-stage pattern of “slow–fast–steady”, while the degradation rates of NO₂ and HC followed a “fast–slow–steady” pattern. Increasing the void ratio and the photocatalyst dosage yielded similar effects on exhaust degradation efficacy, enhancing the degradation rate and reducing the time required to reach equilibrium. The increase in the void ratio of porous asphalt mixtures and porous cement concrete reduced the time required to reach equilibrium by an average of 4.4 and 2.3 min for the four pollutants monitored, respectively. Increasing the dosage of photocatalytic material by 2 kg/m³ increased NO degradation by an average of 1.5% and reduced the time required to reach equilibrium by an average of 0.8 min. The degradation rate of porous cement concrete in the first reaction stage was faster than that of porous asphalt mixtures, and the time required to reach equilibrium state increased by 2 min compared to that of porous asphalt mixture. And the impact of specimen thickness on exhaust degradation performance was minimal. Full article

The construction industry is a fundamental sector for the development of countries; however, it produces negative environmental impacts due to the demand for natural resources and the generation of construction and demolition waste (CDW). Therefore, the pursuit of solutions to recycle and reintegrate these wastes, which often accumulate in poorly regulated areas, becomes not only an environmental priority but also an opportunity to transform a problem into an advantage. Utilizing these residues contributes to reducing the pressure on natural resources, minimizes the environmental footprint of the construction sector, and promotes a more sustainable and responsible model that can serve as an example for future generations. The properties of recycled concrete aggregates (RCA) and recycled asphalt pavement (RAP) were determined in order to subsequently obtain the properties of different permeable recycled concrete (RPC) elaborated from a factorial design 2³ with these aggregates. The properties studied were workability, permeability, volumetric weight, compression uniaxial, and bending. Finally, they were studied and correlated with their matrix microstructure by means of TGA and SEM tests, which allowed determining the compounds contained in the various mixtures and their impact on physical–mechanical behavior. The results indicate that RCA and RAP are feasible alternatives for making porous pavements in pedestrian or light traffic areas when recycled aggregates of 3/4” size are included in their matrix, resulting in the optimum dosage of the M5 3/4” mix in this research, whose mechanical properties are: uniaxial compressive strength: 15.39 MPa; flexural strength: 3.12 MPa; permeability: 0.375 cm/s. Full article

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. Full article

Permeable road pavements, due to their open-graded design, suffer from low structural strength, restricting their use in areas with light traffic volume and low bearing capacity. To expand application of permeable road pavements, accurate simulation of stress parameters used in pavement design is essential. A 3D finite element (3D FE) model was developed using ABAQUS/CAE 2021 to simulate pavement stress responses. Utilizing a 53 cm thick permeable road pavement and a 315/80 R22.5 wheel as prototypes, the model was calibrated and validated, with its accuracy confirmed through t-test statistical analysis. Simulations of wheel speeds at 11, 15, and 22 m/s revealed significant impact on pavement depths of 3 cm and 8 cm, while minimal effects were observed at depths of 13 cm and 33 cm. Notably, stress values at a depth of 3 cm with 15 m/s speed in the open-graded asphalt concrete (OGFC) surface layer exceeded those at the speed of 11 m/s, while at a depth of 8 cm in the porous asphalt concrete (PAC) base layer, an opposite performance was observed. This may be attributed to the higher elastic modulus of the OGFC surface layer, which results in different response trends to velocity changes. Overall, lower speeds increase stress responses and prolong action times for both layers, negatively affecting pavement performance. Increasing the moduli of layers is recommended for new permeable road pavements for low-speed traffic. Furthermore, considering the effects of heavy loads and changes in wheel speed, the recommended design depth for permeable road pavement is 30 cm. These conclusions provide a reference for the design of permeable road pavements to address climate change and improve performance. Full article