Cracking In Asphalt Pavements Research Articles

Research on the detection and identification method of internal cracks in semi-rigid base asphalt pavement based on three-dimensional ground penetrating radar

Research on the detection and identification method of internal cracks in semi-rigid base asphalt pavement based on three-dimensional ground penetrating radar

Automated high-resolution asphalt pavement crack segmentation using deep convolutional neural networks with repeated hierarchical feature fusion

ABSTRACT Automated collection and detection of asphalt pavement crack conditions are essential for evaluating road conditions and maintenance planning. However, determining crack conditions accurately and efficiently has been challenging due to their small object-to-background information ratio, poor contrast with defect-free regions, and vulnerability to noise, such as stains and shadows. We approach this challenge by developing a series of methods that generate high-resolution asphalt pavement crack segmentation, the HRCrack series, which attends to hairline cracks by repeatedly fusing hierarchical features learned using convolutional neural networks. We validated and compared the models with ten widely used models on six open crack datasets. The results demonstrated that our models outperformed the considered methods on the self-made and six open-source datasets. Our best-performing model, HRCrack48, achieved an optimal dataset scale (ODS) F1 score of 0.948 on the self-made dataset. Our smallest model, HRCrack18s, was the fastest (25 FPS) while still providing competitive performance.

Effects of moisture contents, fracture modes, and temperatures on fracture toughness and crack distribution of asphalt concrete at low-temperature

Low-temperature cracking of asphalt pavements is a major issue in highway construction. The deterioration of fracture resistance in asphalt pavements is accelerated by traffic loads when water infiltrates the cracks. However, previous studies have largely overlooked the effects of moisture content on the low-temperature cracking behaviour of asphalt concrete, particularly under different fracture modes. To address this gap, we investigated the fracture toughness and crack distribution of asphalt concrete using semicircular bending tests under five low-temperature conditions (-10 °C, -5 °C, 0 °C, 5 °C, and 10 °C), five moisture contents (0%, 25%, 50%, 75%, and 100%), three fracture modes (mode I, mode II, and mixed mode I&II), and two types of asphalt binders (base asphalt binder and styrene–butadiene–styrene modified asphalt binder).

Evaluation for anti-cracking performance of polyurethane grout based on overlay test

Polyurethane grouting has garnered increasing attention in road maintenance, owing to its exceptional interfacial adhesion, mechanical robustness, and chemical resilience. In comparison to conventional SBS-modified asphalt, polyurethane grout offers superior durability and demonstrates an enhanced capacity to inhibit crack propagation within asphalt mixtures. This study investigates the anti-cracking performance of polyurethane grout in comparison to traditional SBS-modified asphalt, utilizing the Overlay Test (OT) to simulate real-world conditions of reflective cracking in asphalt pavements. Results demonstrate that polyurethane grout significantly enhances the crack resistance of asphalt mixtures, manifesting superior durability and resistance to crack propagation at a controlled temperature of 25°C, with a marked increase in the number of loading cycles relative to the control. However, the performance of polyurethane grout is notably diminished under adverse conditions of low temperatures and water immersion. The investigation employs a multi-index evaluation, with gray correlation analysis delineating the efficacy of various indices in appraising crack resistance. Recommending the use of loading cycles, allowable failure times, and cumulative fracture energy as key metrics.

Performance evaluation of welded galvanized steel wire mesh reinforced asphalt pavements

Welded galvanized steel wire mesh is fabricated from longitudinal and transverse steel wires welded at specific intervals, followed by hot-dip galvanizing. To address the issue of asphalt pavement cracking, this study incorporates the welded galvanized wire mesh between the base and surface layers, thereby reducing the stress-strain levels of the pavement structure and mitigating the stress concentration at cracks. This results in a novel reinforced asphalt pavement structure. To validate the road performance of asphalt mixtures reinforced with welded galvanized steel wire mesh, this paper presents an indoor experimental study comparing various reinforcing materials: unreinforced, glass fiber geogrid, a polyester fiberglass geotextile, and 1.0 mm welded galvanized steel wire mesh. The results demonstrate that welded galvanized steel wire mesh significantly constrains asphalt mixture deformation under wheel loads, enhancing shear strength by 58.9 % compared to unreinforced asphalt mixtures, and exhibiting robust high-temperature deformation resistance. Moreover, the flexural tensile strength of asphalt mixtures reinforced with welded galvanized steel wire mesh increased by 36.3 %, and the maximum bending and tensile strains rose by 79.9 %, showcasing exceptional low-temperature crack resistance and crack propagation properties. Additionally, the fatigue life of the asphalt mixtures was markedly improved. Comprehensive analysis indicates that welded galvanized steel wire mesh is cost-effective, enhances the integrity and continuity of asphalt pavements, and extends their service life. Over the pavement's life-cycle, this method reduces overall investment, providing a robust basis for extensive application of welded galvanized steel wire mesh in asphalt highways.

Research on the Propagation Law of Temperature-Induced Reflective Cracks in Semi-Rigid Base Asphalt Pavement

In order to solve the problem of reflection cracks in semi-rigid base asphalt pavement, a study of temperature-type reflection crack expansion is carried out according to the typical climatic characteristics of Guilin, Guangxi Province. According to the theory of fatigue fracture mechanics, the stress intensity factor analysis at the crack tip is carried out, the reflection crack propagation life under single-factor and multi-factor changes is calculated using the Paris fatigue growth formula, and the prediction model of the propagation life of reflected crack under the action of a temperature gradient is established. The results show that the propagation life of temperature-type reflective cracks increases with an increase in the thickness of the middle course and bottom course, and decreases with an increase in the surface course modulus, base course modulus, base course thickness, and temperature decrease. The prediction model includes the factors that have a great influence on the reflection crack extension and provides a theoretical supplement and reference for the design and calculation of asphalt pavement structure in areas with large temperature differences.

Introducing the mineral powder to strengthen polyurethane grouting materials for crack repair of asphalt pavements

Cracking in asphalt pavement may lead to structural distress while existing crack repair materials have significant shortcomings in terms of cost and construction efficiency. This study incorporates mineral powder into the polyurethane grouting materials to provide a more economical and durable solution for repairing cracks in asphalt pavement. The results of bonding and tensile tests show that excessive mineral powder may deteriorate the mechanical properties of polyurethane grouting materials, which is caused by the agglomeration of mineral powder observed by the microscale characterization. Characterization tests indicate that ultraviolet exposure results in the evolution of the chemical components and thermal stability of polyurethane grouting materials, subsequently causing the degeneration in the mechanical properties. The addition of mineral powders was found to increase the tensile strength of polyurethane grouting materials after Ultraviolet aging by 12 %, while the elongation at break measured in tensile tests remained essentially unchanged. The results of the splitting test, bending test, and immersion Marshall test prove the enhanced low-temperature property and moisture resistance of mineral powder-modified polyurethane grouting materials as compared to the styrene-butadiene-styrene emulsified asphalt. The economic analysis shows that this study presents a practical approach to cost-effective asphalt pavement crack repair, offering insights for enhancing the durability of asphalt pavements.

Two-stage algorithm for automatic repair of pavement cracks

PurposeTo develop an automated system for identifying and repairing cracks in asphalt pavements, addressing the urgent need for efficient pavement maintenance solutions amidst increasing workloads and decreasing budgets.Design/methodology/approachThe research was conducted in two main stages: Crack identification: Utilizing the U-Net deep learning model for pixel-level segmentation to identify pavement cracks, followed by morphological operations such as thinning and spur removal to refine the crack trajectories. Automated crack repair path planning: Developing an enhanced hybrid ant colony greedy algorithm (EAC-GA), which integrates the ant colony (AC) algorithm, greedy algorithm (GA) and three local enhancement strategies – PointsExchange, Cracks2OPT and Nearby Cracks 2OPT – to plan the most efficient repair paths with minimal redundant distance.FindingsThe EAC-GA demonstrated significant advantages in solution quality compared to the GA, the traditional AC and the AC-GA. Experimental validation on repair areas with varying numbers of cracks (16, 26 and 36) confirmed the effectiveness and scalability of the proposed method.Originality/valueThe originality of this research lies in the application of advanced deep learning and optimization algorithms to the specific problem of pavement crack repair. The value is twofold: Technological innovation in the field of pavement maintenance, offering a more efficient and automated approach to a common and costly issue. The potential for significant economic and operational benefits, particularly in the context of reduced maintenance budgets and increasing maintenance demands.

Automated repair of asphalt pavement cracks and potholes utilizing 3D printing and LiDAR scanning

This study introduces a method for automatic repair of asphalt pavement cracks and potholes using 3D printing and LiDAR scanning. A scanning method was developed to accurately detect and represent cracks and potholes in a 3D model. To address the limitations of LiDAR scanning, such as missing data points caused by the irregular shapes of cracks and potholes, the screened Poisson method was applied to reconstruct the missing data points. These models were validated through both theoretical calculations and sand test. In addition, the research focuses on optimizing key 3D printing parameters, such as printing temperature and printing speed, to enhance performance of crack repair throughout semi-circular bending test. Direct tensile strength test was employed to assess the impact of waste materials (e.g., rubber tire powder and waste glass) on the bond strength of filled sample. The results indicated a volume difference of 2–5 % between the scanning method and the sand test method, demonstrating high accuracy in detecting and reconstructing 3D cracks/potholes. Binders modified with 10 % rubber tire powder, or 20 % waste glass exhibited the highest tensile strength of 212 kPa and 207 kPa, respectively. However, using more than 30 % waste materials is not recommended due to a significant reduction in bond strength compared to conventional binders. An optimal 3D printing speed of 180 mm/min and a temperature of 117 °C are recommended for use in 3D printing in laboratory conditions. It was also noted that higher printing speeds decrease indirect tensile strength, highlighting the importance of balanced parameter settings.

Temperature variations and frozen zone migration: assessing the influence of climate change on fatigue cracking in roadway asphalt pavements – a case study of seven provinces in China

Both temperature fluctuations and migrations in frozen zone distribution resulting from climate change can influence fatigue cracking in asphalt pavement. This study focused on seven provinces in China, utilising climate prediction data from 2021 to 2100 to analyse temperature variations and frozen zone migrations over the next 80 years. The study calculated the fatigue cracking of asphalt pavements on freeways and secondary roadways under the influence of these two factors. Additionally, a Fatigue Cracking Climate Index (FCCI) was introduced to reflect the extent of climate change impact on fatigue cracking. Research findings indicate that the rising temperatures associated with climate change adversely affect fatigue cracking. Conversely, the migration of frozen zones tends to alleviate this adverse impact. Overall, fatigue cracking is gradually exacerbated under the influence of climate change. In the region of interest, a majority of the asphalt pavements experience negative effects from climate change on fatigue cracking.

Experimental and simulation-based engineering of calcium alginate self-healing asphalt capsules

An emerging technology to mitigate the cracking of asphalt pavements is the use of self-healing capsules embedded in asphalt mixtures. In this study, self-healing capsules were fabricated by encapsulating asphalt rejuvenators with calcium alginate shells. While past studies have used a “brute force” design process for such capsules, the design and formulation of these can be optimized through careful consideration of chemical interactions and crack healing mechanisms. In this study, experiments and molecular dynamics (MD) simulation were used to engineer capsule–rejuvenator formulations to mitigate premature failure of capsules and improve self-healing efficiency. To explore the thermodynamic process, the inter-diffusion coefficient and blending degree between materials in the capsule system were evaluated at different temperatures and capsule designs to determine the ratio of capsules which survive mixing and compaction through molecular scale studies. MD provided an understanding of healing behavior by simulating and quantifying the fracture–healing–fracture process of the binder–capsule system. The experiments verified the MD model by quantifying oil release percentage from micro-extraction and recovery and fine aggregate matrix (FAM) healing efficiency. The research revealed that the interaction between asphalt binder, rejuvenator, and capsules highly depended on their chemical compositions and that the dose of capsule content influences the penetration degree, and structural failure process. Polymeric capsules experienced significant premature failure and content release at high temperatures (160 °C) compared to intermediate temperatures (25 °C) due to enhanced thermal movement. To optimize capsule performance, rejuvenators C and E, which had higher viscosities, required 30%–40% calcium alginate, while rejuvenator A with lower viscosity needed 40%–60% calcium alginate. Rejuvenators with more asphaltenes were more sensitive to the capsule shell protection effect, and strengthened healing efficiency, while rejuvenators with more aromatics resulted in better wetting and diffusion processes during healing. The healing index, derived from FAM experimental healing test and validated by simulations, indicated that approximately 40% shell material effectively prevented capsule breakage and resulted in a 50% reduction in healing capacity. This research therefore established a framework for engineering a combination of capsules for use at pavement scale based on an understanding of chemical interactions, mechanical properties, and experimental verification.

Numerical analysis of the effects of subgrade settlement on top-down cracking in epoxy asphalt pavement

Numerical analysis of the effects of subgrade settlement on top-down cracking in epoxy asphalt pavement

Automated quantification of crack length and width in asphalt pavements

AbstractRapid, accurate, and fully automated estimation of both length and width of asphalt pavement cracks, essential for achieving a proactive asset management, presents a significant challenge, primarily due to limitations in the effectiveness of automatic image segmentation and the accuracy of crack width and length estimation algorithms. To address this challenge, this paper introduces the Branch Growing (BG) algorithm, specifically designed for crack length estimation in asphalt pavements, along with an optimized OrthoBoundary algorithm tailored for crack width estimation. Leveraging four widely adopted deep learning models for asphalt pavement crack segmentation, four distinct sets of image segmentation results have been produced. Subsequently, a comprehensive evaluation has been conducted to assess the effectiveness of both crack dimensions estimation algorithms. The findings demonstrate that the integration of the BG algorithm, the optimized OrthoBoundary algorithm, and the fully convolutional network with the HRNet backbone achieve a prediction accuracy of 80.21% for crack length estimation and 84.32% for average width estimation. Moreover, the image processing speed, at a resolution of 3024 × 3024, can be maintained at approximately 5 s, with average width estimation observed to be up to 9.1‐fold faster than the unoptimized OrthoBoundary algorithm. These results signify advancements in automated crack quantification methodologies, with implications for enhancing civil infrastructure maintenance practices.

Study on Low Temperature Cracking Resistance of Carbon Fiber Geogrid Reinforced Asphalt Pavement Surface Combined Body.

Currently, there are limitations in the research on the use of carbon fiber geogrids to prevent low-temperature cracking in asphalt pavements. This study aims to comparatively investigate the effects of carbon fiber-based geogrid type and dense-graded asphalt concrete mixture (AC) surface combined body (SCB) type on the low-temperature cracking resistance of reinforced asphalt pavement through low-temperature bending damage tests. Two geogrid types were prepared: a carbon fiber geogrid (CCF) and a glass/carbon fiber composite qualified geogrid (GCF). Two SCB types were studied: AC-13/AC-20 and AC-20/AC-25. The results show that the improvement in the flexural tensile strength of CCF is similar to that for GCF. Moreover, under reinforced conditions, the improvement in the low-temperature cracking resistance of AC-20/AC-25 is better than that for AC-13/AC-20 by 16.26-24.57%. Based on the analysis, the reasonable ratio range of the aperture sizes to the major particle sizes in the dense gradation can achieve a more effective interlocking effect. This can improve the low-temperature cracking resistance of carbon fiber-based geogrid-reinforced samples. Then, increasing the bending absorption energy is a key way of improving the low-temperature cracking resistance of carbon fiber-based geogrid reinforcements. Eventually, the fracture type of carbon fiber-based geogrid-reinforced samples is a mixed plastic-brittle fracture. These results can provide a reference for the road failure analysis of geogrid-reinforced asphalt pavement.

Dynamic response and sound radiation of cracked asphalt pavements under moving loads and variable thermal profiles

ABSTRACT This study investigates the acoustic performance and dynamic response of cracked, viscoelastic porous asphalt pavements under moving loads and variable thermal conditions. Realistic pavement cracks are modelled using an advanced line spring model with fracture compliance coefficients. The novelty lies in the synergistic integration of a heterogeneous triple-porosity media model, a non-uniform depth-dependent temperature profile, and an advanced fracture mechanics-based line spring model with arbitrary crack orientation. Variations in temperature that are uniform, linear, and nonlinear with respect to the thickness layer axis are taken into account. The governing equations are derived by Hamilton’s principle and solved analytically via Fourier-Laplace transforms. The acoustic pressure is first-time predicted through Rayleigh integral analysis. Durbin’s numerical inversion validates the model’s accuracy versus sophisticated finite element simulations. Parametric analysis offers new insights into the effects of crack length, pore size distribution, loading frequency, and thermal gradients on noise pollution and fatigue cracking. The integrated chemo-thermo-mechanical modelling enables optimal structural design and accelerated pavement testing to limit acoustic radiation and premature failure in porous asphalt pavements. It allows for the development of noise-reducing porous asphalt mixtures by modifying aggregate gradation, binder content, and air void distribution.

USE OF INNOVATIVE TECHNOLOGIES IN THE CONSTRUCTION OF ROAD PAVEMENTS

Problem statement. Ukraine, on its way to European integration, faces the challenge not only of joining the European Union, but also of adapting its infrastructure to high European quality standards. After the end of the war, it is necessary not only to rebuild the destroyed roads, aerodromes and buildings, but also to guarantee the sustainability and durability of infrastructure facilities. One of the key industries where innovations can make a significant difference is road construction. Asphalt and concrete are the most common building materials in the construction of flexible and rigid pavements. Innovative technologies for repairing cracks in asphalt and concrete road pavements are constantly evolving. New methods and materials are being sought for more efficient and long-term maintenance of the road surface. The use of advanced technologies allows us to improve the quality of repairs, extend the service life of roads and reduce their environmental impact. Innovative approaches to crack repair help to ensure safety and comfort on the road for all road users. The purpose of the article is to analyze foreign experience in the application of effective innovative technologies in the construction of road pavements and to substantiate the feasibility of using a self-healing top layer of flexible and rigid asphalt and concrete pavements in Ukraine based on the analysis of their properties. Conclusions. The inclusion of self-healing properties in asphalt concrete pavements is an effective method for increasing their service life and achieving environmental friendliness of pavements. Existing and advanced self-healing technologies suitable for use in asphalt pavements, namely, the inclusion of healing agents, induction heating, and hybrid technologies, have been investigated. The mechanisms of self-healing of concrete have been studied: autogenous, based on autonomous bacteria, and based on autonomous capsules. Research on self-healing pavements is aimed at developing a smart and efficient pavement system capable of self-assessment and automated crack repair. The choice of technology should be based on its ability to effectively repair damage and cracks in asphalt and concrete, providing long-term and reliable protection.

Optimum moment to heal cracks in asphalt pavement by means of waste carbon fiber-enhanced electromagnetic induction heating during multiple damage-healing cycles

This study investigated the optimal timing for healing asphalt pavement cracks using waste carbon fibers (WCFs) reinforced electromagnetic induction (EMI) technology through multiple "damage-healing" cycles, focusing on mechanical and fatigue performance. Initially, an extensive research project was carried out to evaluate the rate of induction heating, surface temperature decline rate, and effective heating depth of the asphalt mixture. Subsequently, from a mechanical performance perspective, semi-circular bending (SCB) tests were employed. By setting four different load termination conditions, the extent of cracking in the specimens was quantitatively controlled, followed by multiple "damage-healing" tests to analyze the impact of healing timing on the mechanical properties and healing efficiency of the asphalt mixture. Lastly, from the perspective of fatigue performance, using the four-point bending fatigue test (4 PB), the fatigue damage extent of specimens was quantitatively controlled through the attenuation rate of stiffness modulus. Multiple "damage-healing" tests were carried out at four different healing timings to study the effect of healing timing on the fatigue performance and healing efficiency of the asphalt mixture. The results indicated that WCFs improved the heating performance of asphalt mixture, enabling 5 cm-thick specimens to be fully heated within 6 min. Both SCB and 4 PB tests yielded similar conclusions: in the process of multiple "damage-healing" cycles, earlier healing interventions were beneficial for the recovery and maintenance of the mechanical properties of asphalt mixtures and effectively extended their service life. However, the fatigue tests also revealed that overly early self-healing interventions, where cracks were insufficiently formed, did not fully exploit the potential of the healing process. Conversely, healing interventions conducted too late were extremely detrimental to the restoration of mechanical characteristics and the prolongation of the asphalt mixture's lifespan.

Coupled effects of UV radiation and freeze–thaw cycles on the fracture behavior of asphalt concrete

The Qinghai-Tibet Plateau in China is characterized by extreme climate conditions, including intense ultraviolet (UV) radiation, frequent freeze–thaw cycles (FTCs), and significant temperature fluctuations. These conditions contribute to severe cracking in asphalt pavements. This study aims to investigate the impact of coupled damage from UV radiation and FTCs on the fracture behavior of asphalt concrete. To simulate the coupled environmental damage (CED) experienced by asphalt pavement in the field, an alternating two-factor laboratory procedure was developed. This procedure reflects the climatic conditions of the Qinghai-Tibet Plateau. The semi-circular bending test, combined with digital image correlation technology, was employed to evaluate the effects of temperature and CED cycles on fracture-related parameters of asphalt concrete. These parameters include the load–displacement curve, fracture toughness, and fracture energy. Fracture behavioral characteristics such as horizontal strain, crack length, crack propagation path, and crack mouth opening displacement were also analyzed. The results indicate that coupled damage from UV radiation and FTCs significantly weakened the fracture resistance of asphalt concrete. Compared with other fracture-related indicators, the most significant reduction observed was the fracture energy of 68.1%. The two environmental factors exhibited a mutually reinforcing effect on the fracture properties of asphalt concrete, with low temperatures further intensifying their influence. CED cycles delayed the initiation of cracks in asphalt concrete but accelerated crack propagation. This led to a reduction in time to failure by up to 57.6% and a maximum reduction in horizontal strain of 24%. Additionally, the cracking propagation path of asphalt concrete became more linear with increased crack mouth opening displacement. Future research should focus on the evolution of damage accumulation in asphalt concrete under CED cycles, with the goal of establishing predictive models for long-term service life.

An eco-friendly crack sealant approach for asphalt pavement by using laboratory tests and molecular dynamic simulation

Waste engine oil (WEO) is detrimental to the environment and challenging to recycle on a large scale. Fortunately, the utilization of WEO as an additive in asphalt pavement crack sealant offers both economic benefits and engineering feasibility. In this study, an eco-friendly crack sealant was prepared using WEO and crumb rubber (CR) modified asphalt (WCRA). The viscoelasticity, storage stability, adhesion, and water resistance properties of the sealant were tested to evaluate its suitability for crack repair. In addition, molecular dynamic (MD) simulation was employed to elucidate the interface adhesion mechanism of the sealant-crack wall interface. The test results demonstrated that the viscosity of the sealant is primarily proportional to the content of CR and inversely proportional to WEO. Furthermore, the storage stability is satisfactory after the addition of moderate WEO. The medium and high temperature flexibility of the sealant is between base asphalt and SBS-modified asphalt. Based on the laboratory tests, 35% (by weight of base asphalt) microwave-treated CR and 25% (by weight of CR) WEO are the optimal proportions for preparing the sealant. MD simulation demonstrated that CR inhibits the diffusion of asphalt components and aggregates asphaltenes in close proximity to the crack wall surface. WEO not only stimulates molecular activity but also maintains the equilibrium of the asphalt colloid system, which is conducive to the penetration and water resistance of the sealant. The study will provide a reference for the utilization of waste materials and the cost-effective repair of asphalt pavements.

Influence of Interaction between Microcracks and Macrocracks on Crack Propagation of Asphalt Concrete.

This paper aims to reveal the interaction relationship between microcracks and macrocracks and the influence of the interaction on the crack propagation behavior. A theoretical model of asphalt concrete was established for the interaction between microcracks with different crack densities and a macrocrack. And a meso-structure model of AC-13 dense-graded asphalt concrete was established by combining the Talyor medium method and the DEM (discrete element method). Macro and micro parameters, such as the stress-strain characteristics, crack evolution parameters, and crack tip stress field, were obtained through a semi-circular bend virtual test and used to study the characteristics of crack propagation under the interaction between microcracks and the macrocrack. The results indicate that the interaction has an effect throughout the process of asphalt concrete damage, and shows shielding and acceleration effects as the microcrack density changes. When the microcrack density is low (f3 ≤ 0.8), the crack propagation process, which is affected by the interaction effect, exhibits significant differences, and the interaction effect shows the shielding effect. When the microcrack density is high (f3 > 0.8), the fracture stage is mainly affected by the interaction effect, which shows the acceleration effect. The results provide a predictive theoretical and numerical model for low-temperature cracking of asphalt pavement, and theoretical support for the design, maintenance, and upkeep of long-life pavement.