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To explore the effect of waterborne polyurethane (WPU) on the performance of styrene-butadiene rubber (SBR) emulsified asphalt and broaden the application range of polymer-modified emulsified asphalt, WPU-SBR-modified emulsified asphalt with 0%, 3%, 6%, 9%, and 12% WPU was prepared. The penetration, softening point, ductility, and storage stability tests were used to explore the effect of different contents of WPU on composite-modified emulsified asphalt. Meanwhile, the rheological properties of five modified emulsified asphalts were analyzed by temperature scanning test, multiple stress creep recovery test, and low-temperature bending creep test. The results show that the addition of WPU improved the performance of SBR emulsified asphalt, and the improvement effect varied with the addition amount. With the increase of WPU content, the penetration and unrecoverable creep compliance Jnr of WPU-SBR-modified emulsified asphalt gradually decreased, and the softening point, rutting factor G*/sinδ , and creep recovery rate R gradually increased, indicating that the high-temperature stability of modified emulsified asphalt was enhanced, and when the WPU content was 9%, the best improvement effect was obtained. However, excessive content of WPU will deteriorate the low-temperature performance of WPU-SBR-modified emulsified asphalt, and thus the content of WPU should be appropriately selected in practical engineering applications. [ABSTRACT FROM AUTHOR]

• Evolution of CRMA-aggregate interface molecular behavior before and after water intrusion was revealed. • The real interfacial damage characteristics of compacted mixtures were investigated by DCT test. • The effect of water on CRMA-aggregate interfacial failure patterns was investigated. The incorporation of crumb rubber (CR) makes the asphalt-aggregate interfacial properties highly complex and uncertain, while water is a key environmental factor causing interfacial failure. This paper aims to evaluate the characteristics of crumb rubber modified asphalt (CRMA)-aggregate interaction and the interfacial failure mechanism under the influence of different material properties and water at ambient temperature. Firstly, the CRMA-aggregate interfacial behavior before and after water intrusion is investigated using molecular dynamics simulations at the molecular scale. Next, the failure process and characteristics of the CRMA-aggregate interface were analyzed using the disk-shaped compact tension (DCT) test at the macro scale. Finally, the effect of water intrusion on the interface failure mode was analyzed through image processing. The results show that CR enhances binder cohesion and significantly affects its adhesion to aggregates with high CaO and MgO contents regardless of the presence of water. The asphalt concentration distribution on the CaO and MgO surfaces is more concentrated with higher peak concentration, leading to superior interfacial adhesion and water damage resistance with binder, while Al 2 O 3 and SiO 2 were inferior. The use of asphalt with higher creep stiffness, high-strength alkaline aggregates, and smaller CR particle size is beneficial for enhancing the CRMA binder-aggregate interfacial fracture performance. Water intrusion severely affected the interfacial adhesion, resulting in a significant increase in the proportion of adhesion failure, which is the main cause of the deterioration of the interface properties. The findings of this study provide insights into the factors affecting the CRMA-aggregate interfacial behavior, which facilitate the accurate design and application of high-strength durable CRMA mixtures. [ABSTRACT FROM AUTHOR]

The bonding quality of the mixture is critical to the longevity and durability of the asphalt pavement. This paper aims to investigate the influence patterns and intrinsic relationships of various factors including binder, aggregate, moisture, and anti-stripping agents on asphalt-aggregate bonding performance and mixture failure characteristics. Specifically, the influence of various factors on asphalt-aggregate bonding strength was investigated through binder bonding strength (BBS) tests. Next, the disk-shaped compact tension (DCT) and indirect tensile (IDT) tests were used to investigate the influence of different factors on the bonding failure characteristics of mixtures from the perspectives of fracture failure and water damage, respectively, and finally the correlation between the asphalt-aggregate bonding and the mixture failure characteristics was explored. The BBS test results show that crumb rubber significantly deteriorates the bond strength while SBS incorporation shows an insignificant effect on bond strength, and aggregates containing more alkaline components favor bond strength enhancement. The DCT and IDT test results reveal that SBS enhances the fracture and water damage resistance of the mixture, while crumb rubber is detrimental to it. Water causes deterioration of asphalt-aggregate adhesion and reduces the fracture resistance of the mixture. Mixtures containing anti-stripping agents and alkaline aggregates exhibit enhanced resistance to fracture failure and water damage. The fracture energy ratio is preliminarily validated as a new evaluation index for water damage resistance of asphalt mixtures. The correlation analysis shows that the pull-off tensile strength (POTS) correlates well with fracture resistance under consistent asphalt conditions, and the POTS ratio (R p) could effectively reflect the moisture damage resistance of the mixture. This study provides valuable insights into selecting the optimal material combination for superior bonding performance in engineering practice and enhancing pavement durability. • The effect of various factors on asphalt-aggregate bonding was evaluated. • The bonding failure behavior of mixtures was explored from the perspectives of fracture and water damage. • A novel index was proposed to evaluate the water damage resistance. • The correlation of asphalt-aggregate bonding with mixture failure characteristics was analyzed. [ABSTRACT FROM AUTHOR]

The incorporation of rubber powder leads to a high degree of complexity in the CRMA binder-aggregate interfacial properties, which directly affects the interfacial adhesion performance. The objective of this study is to investigate the variation of SARA fractions of CRMA binder during the adhesion process and to explore the intrinsic relationship between the components and the adhesion properties. To this end, the staged extraction tests were performed to extract CRMA binder layers on the aggregate surface. After each extraction, the binder layer was evaluated in terms of its SARA fraction contents and molecular weight distribution. Additionally, the pull-off tensile strength (POTS) was used to assess the adhesion of the binder-aggregate interface through the binder bond strength (BBS) test. Finally, the correlation between the SARA fractions of CRMA binder and interface adhesion of CRMA binder-aggregate system was analyzed. The results showed that the CR tends to absorb the lighter components of base asphalt, the variations in SARA fractions and molecular weight distribution during the aggregate adhesion to CRMA binders occurred mainly in the third and fourth elution layers. Pen 70 CRMA binder and limestone show the best adhesion properties among all the binder and aggregate types. The increase in CR size and the decrease in CR dosage are favorable for the adhesion of CRMA binders to aggregates. Furthermore, asphaltenes and resins are positively correlated with adhesion, while aromatics and saturants are negatively correlated with adhesion. The correlation between SARA content and adhesion varied depending on the aggregate type. • An equal-mass staged extraction test procedure for CRMA binder was proposed. • The SARA fractions changed drastically in the third and fourth elution layers. • The effect of different factors on CRMA binder-aggregate adhesion was evaluated. • The correlation between adhesion and the SARA fractions of CRMA was analyzed. [ABSTRACT FROM AUTHOR]

Bitumen materials will occur a physical hardening effect when stored isothermally in a low-temperature environment, and ignoring the physical hardening factor has become one of the important reasons for premature cracking of asphalt pavement during the service period. This paper investigates the response of bitumen binder and bitumen mastic to physical hardening effects at different storage temperatures and times using the bending beam rheometer and dynamic shear rheometer. The response of the material to physical hardening effects is analyzed through temperature index system changes, mathematical model fitting, and stiffness master curve fitting. Results indicate that the response of the material to physical hardening effects can be classified into two stages: the rapid growth and the gradual stabilization periods. The response time of these two stages is related to factors such as aging degree and storage temperature. The physical hardening effect will cause the temperature loss of the material at low temperature, and its influence law on T S 60 = 300 MPa and T m 60 = 0.300 is different. It is recommended to extend the isothermal storage time specified in the test from 1 h to 9 h, considering the time cost and the change in temperature index. Moreover, the stiffness master curve study revealed the occurrence of the "tail drift" phenomenon. • Physical hardening effects cause temperature loss in bitumen, even over a grade. • Recommend extending BBR test storage to 9 h for better scientific validity. • "Tail drift" occurs during the fitting of the stiffness master curve. • The Logistic model can well fit the S and m values in the physical hardening process. [ABSTRACT FROM AUTHOR]

• A novel de-icing fiber permeable mixture (DFPM) is prepared. • The water permeability, road performance and de-icing performance of DFPM were evaluated. • A long-term performance test process was designed to predict the de-icing longevity of DFPM. • DFPM with 0.3% fiber and 5% de-icing agent shows superiority in performance and cost. The complex and changeable service conditions require pavements with greater functional diversity and environmental adaptability. In this paper, the de-icing fiber permeable asphalt mixture (DFPM) that satisfied the multiple service requirements of rapid drainage and ice melting in various seasons was proposed. Various performance characterization tests were utilized to evaluate the permeability and de-icing properties and the pavement performance of the mixtures with different contents of de-icing agents and fibers. Meanwhile, the high temperature dynamic water scouring experiment was designed to predict the effective de-icing life. The results show that adding de-icing agents and fibers slightly affects the water permeability of the mixtures. The incorporation of de-icing agents is beneficial to the high temperature performance yet detrimental to the low temperature behavior and water stability, while the incorporation of fibers compensates for the negative effect; the de-icing performance of the mixture correlates positively with the amounts of de-icing agents and correlates negligibly with the fiber incorporation. DFPM with 0.3% fibers and 5% de-icing agent shows superiority in performance and cost and is recommended for practical applications. Therefore, building a composite functional asphalt pavement with excellent performance appears feasible while creating a pavement micro-ecology by applying de-icing fibers permeable asphalt mixtures. [ABSTRACT FROM AUTHOR]

[Display omitted] • Effects of various factors on asphalt-aggregate adhesive property were evaluated. • The pull-off test was improved to precisely control the asphalt film thickness. • SARA composition had the most significant effect on interfacial bond strength. • C value correlated significantly with bond strength of asphalt-aggregate interface. The performance of the asphalt binder-aggregate interface is an essential guarantee of the stability and durability of asphalt pavements. The objectives of this paper are to investigate the effects of various factors (test conditions, material properties) on the interfacial adhesive properties of asphalt binder-aggregate systems and to analyze the correlation between the bond strength and interface interaction. For this purpose, the improved pull-off tests under various temperatures, loading frequencies and asphalt film thickness were carried out to determine the test conditions for interfacial adhesion failure. The interfacial bond strength of various asphalt binders-aggregates and the corresponding interaction values were tested according to the determined test conditions and the correlation between them was analyzed. The results show that the bond strength between asphalt binder and aggregate was negatively correlated with temperature and positively correlated with loading rate, and there was an optimal film thickness. Among the selected minerals and aggregates, calcite and limestone presented the best bonding properties with asphalt binder respectively. Asphaltenes and resins enhanced the bond strength of asphalt binder-aggregate, while saturates and aromatics weakened the bond strength of asphalt binder-aggregate. The short-term aging of asphalt binder was beneficial to the bonding of binder and aggregate, whereas the long-term aging of asphalt binder was detrimental. Among the material properties factors, the SARA composition had the most significant effect on interfacial bond strength. A significant correlation was found between the C value (the preferred interaction parameter) and the bond strength of the asphalt binder-aggregate interface. [ABSTRACT FROM AUTHOR]

With the development of E-commerce, online advertising began to thrive and has gradually developed into a new mode of business, of which Click-Through Rates (CTR) prediction is the essential driving technology. Given a user, commodities and scenarios, the CTR model can predict the user's click probability of an online advertisement. Recently, great progress has been made with the introduction of Deep Neural Networks (DNN) into CTR. In order to further advance the DNN-based CTR prediction models, this paper introduces a new model of FO-FTRL-DCN, based on the prestigious model of Deep&Cross Network (DCN) augmented with the latest optimization technique of Follow The Regularized Leader (FTRL) for DNN. The extensive comparative experiments on the iPinYou datasets show that the proposed model has outperformed other state-of-the-art baselines, with better generalization across different datasets in the benchmark. [ABSTRACT FROM AUTHOR]

Liquid rubber (LR) has been proven to be a valuable asphalt modifier capable of addressing the existing deficiencies associated with crumb rubber–modified asphalt (CRMA), including poor workability and storage stability. Therefore, an accessible preparation method based on olefin metathesis was explored to produce optimal LR from crumb rubber (CR) in the laboratory. This research established the optimal laboratory preparation conditions for LR and investigated the performance of liquid rubber–modified asphalt (LRMA) mixture when used in pavement. A total of 32 LR samples were generated by olefin metathesis and physical swelling under various catalytic and swelling conditions. The physical properties, viscosity, and storage ability of LRMA were evaluated to select the optimal preparation parameters for LR. A comprehensive analysis was performed to compare the physicochemical characteristics of LR and the original CR through microscopic examinations with scanning electron microscopy (SEM), Fourier-transform infrared spectrometry (FTIR), and gel permeation chromatography (GPC). An in-depth evaluation assessed the stability at high temperatures, the properties at low temperatures, and the moisture stability of LRMA and CRMA mixtures. Experimental results showed that the optimal laboratory preparation conditions for LR were a catalyst dosage between 3‰ and 5‰, a catalytic duration of 48 h, a swelling temperature of 160°C, and a swelling time of 8 h. Moreover, LR possessed a smooth surface without rubber particles. The molecular weight and distribution of LR were considerably reduced compared with those of CR after olefin metathesis and physical swelling. The introduction of LR significantly enhanced the cracking resistance of the base asphalt mixture. However, the enhancement effect of LR on the base asphalt mixture to resist high-temperature rutting and moisture damage was inferior to that of CR. [ABSTRACT FROM AUTHOR]

[Display omitted] • Interface behavior of rubber asphalt-aggregates was evaluated using MD simulations. • Impact of aggregate types on the interface is more significant than rubber contents. • Electrostatic contributes a considerable of energy, while van der Waals is limited. • Microcline shows favorable moisture resistance while calcite is the poorest. This paper investigates the interface property between rubber asphalt and aggregates using molecular dynamics simulations to address the adhesion and debonding properties. The effect of aggregate types and rubber contents on rubber asphalt-aggregate systems' adhesion and debonding properties were investigated. The work of adhesion characterized the adhesion property while debonding characteristics were evaluated by the work of debonding and energy ratio (ER). The results show that the impact of aggregate types on the adhesion and debonding between rubber asphalt and aggregates is much more significant than rubber contents. The work of adhesion between four aggregates and rubber asphalt is evaluated as follows: microcline > albite > quartz > calcite. The reason is that the electrostatic energy can considerably contribute to the adhesion at the interface for strong alkali aggregates (microcline, albite) and rubber asphalt, while the van der Waals energy can only contribute nearly 100 mJ/m2 energy for the adhesion. The work of debonding for the four aggregates with rubber asphalt follows the order: microcline > quartz > albite > calcite. Therefore, microcline presents extraordinary performance, while calcite shows the poorest response in moisture resistance. [ABSTRACT FROM AUTHOR]

This article aims to propose an asphalt mixture with deicing and permeable functions to address the dilemma of excessive stormwater runoff during summer and ice accumulation in winter for pavement in southwest China. A peeling test and ice melting test were first conducted to select one powder and one granular anti-icing additive for better deicing performance. Then the effects of anti-icing additive contents on deicing and pavement performance of deicing permeable mixtures were investigated to select the best content. Additionally, the effect of immersion treatment on the pavement performance of deicing permeable mixture was analyzed. The results showed that the rise in additives content would help to improve deicing performance, as expected, regardless of additive type. The optimal content of the powder additive was reached by replacing 80% of the mineral powder, and the optimal mass ratio of granular type was 5% of the mixture. The addition of additives weakened the low-temperature performance and water-stability performance of the permeable mixture, whereas a high-temperature performance was observed when granular additive was adopted. The pavement performance of the mixture with granular additive was better than the mixture with powder additive under different immersion treatments. Overall, the granular anti-icing additive is recommended for use in a permeable mixture. This research is helpful and may provide guidance for the design of deicing permeable asphalt mixtures. [ABSTRACT FROM AUTHOR]

Conventional gradation-based pavement design makes the constructed pavement surface too complex to quantify the contribution of texture on the tire-pavement friction accurately. This study aims to investigate the influence of regular macro-texture characteristics and environmental factors on friction using three-dimensional (3D) printing technology. The variation of friction with different texture shapes, heights, and gaps was investigated under dry and wet conditions. The evolutions of friction under different water film thicknesses and temperatures were also quantitatively analyzed. The results show that all specimens with different texture shapes, heights, and gaps can contribute to large friction under dry conditions, where the British pendulum number (BPN) is larger than 90. The friction sharply decreases under wet conditions, especially for the semi-circular texture specimens. The specimens with positive textures are much better than those with negative textures. The impact of texture shapes is more significant than texture height and gaps under wet conditions, where the texture gaps are relatively insignificant. The friction is slightly linearly increased with the water film thickness while slightly decreasing with the temperature. This study provides a friction-oriented pavement texture design method and manufacturing techonology. [Display omitted] • Evolution of friction with macrotexture and environmental factors were investigated. • Specimens with different shapes, heights, and gaps contribute large dry friction. • Friction sharply decreases under wet conditions, especially for semicircle texture. • Friction is slightly linearly increased with water film thickness. • Friction is slightly decreases with temperature. [ABSTRACT FROM AUTHOR]

To realize the resourceful utilization of roadway waste for recycling and low-carbon construction, two environmental-friendly pavement technologies pertaining to cold recycled foamed asphalt mixture and crumb rubber asphalt (CRA) were combined to prepare foamed rubberized asphalt cold recycled mixture (FRA-CRM). The results indicate that pre-swelled activated crumb rubber (CR) by waste oil with foaming agent can enhance the foaming effect of CRA and reduce the manufacturing temperature by 15 °C, and it presents better fatigue resistance and low-temperature performance. Moreover, the moisture susceptibility, high-temperature rutting resistance, and low-temperature cracking resistance of FRA-CRM have been substantially ameliorated in comparison with traditional foamed matrix asphalt cold recycled mixture. Life cycle assessment analysis shows that compared with conventional hot mix CRA mixture, the production demand of FRA-CRM per 1 t contributes to approximate 45.13 % reduction in greenhouse gas emissions and 51.38 % of energy saving. [ABSTRACT FROM AUTHOR]

The rapid development of global industry has led to the generation of large quantities of industrial waste, resulting in inefficient resource usage and environmental contamination. To improve the utilization of industrial waste, this study developed ultra-high-performance geopolymer concrete (UHPGC) by incorporating ground granulated blast furnace slag (GGBS), steel slag, silica fume, quartz sand, and steel fiber. Furthermore, the study explores the mechanical properties, durability, microstructural characteristics, and environmental benefits of UHPGC of steel slag (0 %, 10 %, 20 %, 30 %, and 40 %) and steel fiber (0 %, 1 %, 2 %, and 3 %) contributions. Results show that as the amount of steel slag increased from 0 % to 40 %, the flowability increased by 25.0 %, while compressive and flexural strengths decreased by 15.9 % and 30.1 %, respectively. With an increase in steel fiber dosage from 0 % to 3 %, flowability decreased from 222 to 162 mm, but mechanical strength gradually increased. The steel slag exhibited excellent durability properties after 300 freeze-thaw cycles and 18 sulfate attack cycles when the steel slag dosage was 40%. The compressive strength and the relative dynamic modulus of elasticity remained at 84.8 MPa and 75.1%, respectively. Microscopic analysis revealed that all specimens formed relatively dense microstructures with few pores and produced a large amount of gel, contributing to the enhanced durability of UHPGC. However, increasing the dosage of steel slag resulted in a gradual increase in the diffraction peaks of chromite (Cr 2 O 4), indicating an increase in unreacted steel slag. Steel fibers significantly improved the mechanical strength and durability of UHPGC. GGBS, steel slag, and steel fibers were the major environmental factors, particularly in terms of GWP and PED. The development of UHPGC using industrial waste slag as raw material can significantly promote the extensive utilization of steel slag in concrete and contribute to environmental sustainability. [Display omitted] • The steel slag improves the flowability, sulfate resistance, and freeze-thaw resistance of UHPGC. • Steel fiber improves the mechanical strength, sulfate resistance, and freeze-thaw resistance of UHPGC. • All the UHPGC have formed relatively dense microstructures with few pores. • GGBS and steel slag cooperate to promote the formation of late-stage C-S-H gel. [ABSTRACT FROM AUTHOR]

Energy consumption is caused by the rolling resistance of tires as a vehicle moves forward, which contributes to resource consumption and the greenhouse effect. The objective of this paper is to investigate the variation of tire-pavement rolling energy consumption under different operating condition factors. For this purpose, a rolling finite element dynamic model was developed based on real tire and road contact. The correlation between the effective radius and free angle is determined during the free rolling process. The variations of different working conditions on rolling energy consumption under tire-road coupling were analyzed according to both tire and pavement factors, and the influence factors were analyzed by grey correlation analysis. The results show that the factors affecting the significance of rolling energy consumption in descending order are tire load, tire pressure, coefficient of friction, pavement stiffness, and rolling speed. Specifically, energy consumption can be increased by increasing the tire load or friction coefficient, the cumulative increase of rolling energy consumption reaches 68.3% and 14.51%, respectively. Energy consumption can be decreased by increasing the tire pressure or pavement stiffness, the cumulative decrease in energy consumption is 20.45% and 5%, respectively. In addition, the rolling energy consumption increases and then decreases within an increasing speed range(10–80 km/h). The speed trend inflection point is 20 km/h. The research results can provide a technical reference for the development of a low-energy consumption design scheme for tire-pavement systems. To better serve the construction needs of green low-carbon and sustainable road transportation. • Tire-pavement FE rolling model was built using ABAQUS with good reliability. • The rolling energy consumption linearly increases with tire load and friction coefficient. • Tire load has the highest impact on dissipation energy, followed by tire pressure, friction coefficient, rolling speed, and pavement stiffness. • The tire and pavement influence factors were analyzed by grey relational analysis. [ABSTRACT FROM AUTHOR]

Emulsified asphalt cold recycled technology has received great attention for its low carbon and environmental protection. There have been many researches on the performance improvement of emulsified asphalt cold recycling mixture (CRME) and its achievements, but there lacks systematic sorting. Based on this, this study summarizes the related research from the performance formation mechanism and influencing factors. Firstly, the demulsification mechanism of emulsified asphalt and the performance formation mechanism of CRME are summarized. Secondly, the influence of asphalt material (type and content), aggregate type (new aggregate, RAP), gradation, additives (regenerant, cement, fiber, etc.), water consumption and fabrication methods on CRME performance is analyzed. Finally, the future development of CRME is prospected. In the future, the fusion characteristics of old and new asphalt on RAP surface can be studied from multi-scale perspective. Besides, we can combine genome to construct CRME material library and improve the preparation technology standard of CRME pavement. • The development status of emulsified asphalt cold recycling technology was reviewed. • The influence of different factors on the strength of recycled mixture was analyzed. • The optimal dosage range of different influencing factors was summarized. • The development of emulsified asphalt cold recycling technology was prospected. [ABSTRACT FROM AUTHOR]

• Three-dimensional preset depth crack fatigue propagation models were established. • The propagation of the crack tip section was monitored through the probe. • The fatigue propagation of crack tip inside the semi-rigid base was investigated. Nowadays, it is of non-negligible importance to extend the service life of in-service pavements. As the base form, shrinkage fractures and plate faults are the main reasons for the failure of semi-rigid base and it is of practical significance to study the cracking mechanism of the fracture damage from the microscopic point of view. In order to obtain the fatigue propagation law of the cracks inside the semi-rigid base, a three-dimensional preset depth crack fatigue propagation model was established based on the finite element quasi-static method and ground-penetrating radar detection data, and monitors the propagation of the crack tip section through the probe, obtaining the number of load actions and the crack propagation depth during the destabilization. Subsequently, this paper investigates the stress field distribution and fatigue propagation failure law of crack tip section inside the semi-rigid base based on the ensemble analysis method of stress intensity factor, combined with the macroscopic modulus change of the base structure. The propagation form of single-crack cracks within the base layer is mainly dominated by type I (opening type) cracks, but there are also the remaining two crack propagation trends at the tip. The analysis shows that the smaller the modulus of the semi-rigid base, the less likely the crack is to undergo an initial tip change. In the case of four preset depths, the preset depth of 50 mm is the most vulnerable to crack tip change. Relatively speaking, and the 200 mm preset depth cracks expand the maximum depth when the structure fails in all preset depths. It can be seen from the experiments that the strain field at the crack tip of 50 mm presetting depth is stronger. The strength of stress and strain fields near the crack tip at 200 mm and 150 mm preset depths is mainly related to the modulus of the base layer. The larger the modulus, the stronger the stress and strain fields. The distribution of the field strength at the crack tip of 100 mm and 50 mm presetting depth is less affected by the base layer modulus. In this study, the three-dimensional simulation of the fatigue action of the internal cracks in the semi-rigid base is innovatively proposed, which helps to clarify the distribution of the stress field and the fatigue failure of the internal crack tip of the semi-rigid base, and provides a new way of thinking for the assessment of the service performance of the long-life pavements and the failure mechanism of the microscopic damages. [ABSTRACT FROM AUTHOR]

• Sound absorption characteristics were studied by macro and meso analysis. • The macroscopic influence factors were analyzed by grey relational analysis. • The CT scanning and 3D reconstruction technology were used. • The microscopic void characteristics are analyzed. To explore the sound absorption characteristics of porous asphalt mixture, the effects of macroscopic parameters of asphalt mixture on sound absorption coefficient (SAC) were studied by the sound absorption coefficient test, and the mesoscopic void structure was investigated by industrial computed tomography (CT) and three-dimensional (3D) reconstruction techniques. The results show that the SAC can be increased by increasing the porosity or thickness and reducing the NMAS. The increase of porosity and the decrease of pavement thickness can better absorb high frequency noise (above 1000 Hz). Through the grey correlation analysis, it can be seen that the SAC of porous asphalt mixture is most affected by the porosity. There is a strong linear relationship between the microscopic void characteristic of porous asphalt mixture and the peak and mean value of SAC. [ABSTRACT FROM AUTHOR]

• Airport pavement preventive maintenance three-level evaluation index system is established. • PM decisions are considered as the binary classification problem. • The asphalt pavement decay model is developed based on PCI. • Project-level asphalt pavement PM timing was determined through confusion matrix. Accurate evaluation of the performance of airport pavement can help managers make scientific and systematic preventive maintenance (PM) decisions, ensuring pavement safety and extending service life. To this end, firstly, this paper sorted out the pavement performance evaluation index system, based on which a multi-dimensional evaluation system for PM was proposed, including control indexes, macroscopic indexes, and microscopic indexes. Then, the pavement decay model based on the pavement condition index (PCI) was developed, and the regression model between PCI and International roughness index (IRI) and friction coefficient (μ) was established. Finally, by converting the PM decisions for project-level pavement into a binary classification problem in machine learning, the optimal maintenance thresholds and intervals for PM of each index were determined using receiver operating characteristic (ROC) curve and Kolmogorov-Smirnov (K-S) curve. The optimal threshold represents the threshold when the index can separate the binary classification problem (PM decisions) with maximum probability. Based on confusion-regression model, the pavement performance can be evaluated more comprehensively, and the timing of PM can be accurately determined. The model helps airport managers develop accurate PM plans to address future maintenance needs. [ABSTRACT FROM AUTHOR]

• The impact of asphalt components on the rheology of asphalt was explored. • The impact of asphalt components on the interface interaction was explored. • The impact of asphalt aging degree on rheology and interaction was analyzed. • The impact of filler characteristics on the interface interaction was studied. The strength of the interface between asphalt and filler is relatively low, making it susceptible to stress concentration and damage, which can affect the service life of the asphalt pavement. Current research indicates that there is a significant relationship between the interfacial interaction behavior and the properties of both asphalt and filler. Based on this, this study investigated the influence of both asphalt and filler properties on the interaction behavior of the asphalt-filler interface. Firstly, this study conducted research on existing interaction evaluation indicators and selected Palierne C as the optimal evaluation indicator for this study, which has the weakest correlation with filler volume fraction, in order to avoid the influence of filler volume fraction on experimental results. Secondly, this study analyzed the effects of asphalt SARA components and aging degree on the interface interaction ability between asphalt and fillers, as well as the rheological properties of asphalt. The research results found that the asphaltenes and resins fractions can enhance the interaction ability between asphalt and filler, as well as the high-temperature performance of asphalt. The content of these fractions was positively correlated with the interaction between the interfaces. In contrast, the content of aromatics and saturates fractions was negatively correlated with the interaction capacity. The strength of the interaction was negatively correlated with aging time, and long-term aging inhibited interface interaction to a greater extent than short-term aging. Finally, the mineral and chemical composition of common fillers were analyzed by X-ray diffraction (XRD) and X Ray Fluorescence (XRF). Subsequent studies were carried out on the interaction of the asphalt-filler interface in terms of the mineral composition, chemical composition, and particle size of the filler. It was found that in terms of mineral composition, albite and asphalt have the strongest ability to interact at the same temperature, followed by calcite and the weakest by quartz. In terms of chemical composition, the strongest interaction was between MgO and asphalt, followed by CaO, Fe 2 O 3 and Al 2 O 3 , and the interaction between SiO 2 and asphalt was the worst. In addition, the smaller the particle size of the filler, the greater the interaction capacity. [ABSTRACT FROM AUTHOR]

The feasibility of using ultrasonic Nakagami imaging to evaluate thermal lesions induced by microwave ablation (MWA) in ex vivo porcine liver was explored. Dynamic changes in echo amplitudes and Nakagami parameters in the region of the MWA-induced thermal lesion, as well as the contrast-to-noise ratio (CNR) between the MWA-induced thermal lesion and the surrounding normal tissue, were calculated simultaneously during the MWA procedure. After MWA exposure, a bright hyper-echoic region appeared in ultrasonic B-mode and Nakagami parameter images as an indicator of the thermal lesion. Mean values of the Nakagami parameter in the thermal lesion region increased to 0.58, 0.71 and 0.91 after 1, 3 and 5 min of MVA. There were no significant differences in envelope amplitudes in the thermal lesion region among ultrasonic B-mode images obtained after different durations of MWA. Unlike ultrasonic B-mode images, Nakagami images were less affected by the shadow effect in monitoring of MWA exposure, and a fairly complete hyper-echoic region was observed in the Nakagami image. The mean value of the Nakagami parameter increased from approximately 0.47 to 0.82 during MWA exposure. At the end of the postablation stage, the mean value of the Nakagami parameter decreased to 0.55 and was higher than that before MWA exposure. CNR values calculated for Nakagami parameter images increased from 0.13 to approximately 0.61 during MWA and then decreased to 0.26 at the end of the post-ablation stage. The corresponding CNR values calculated for ultrasonic B-mode images were 0.24, 0.42 and 0.17. This preliminary study on ex vivo porcine liver suggested that Nakagami imaging have potential use in evaluating the formation of MWA-induced thermal lesions. Further in vivo studies are needed to evaluate the potential application. [ABSTRACT FROM AUTHOR]

In this study, the rheological properties and adhesion characteristics of foamed CRA binder were studied. Firstly, the optimum foaming conditions of foamed CRA binder with different crumb rubber powder (CRP) content and foaming agent were studied. Secondly, stress creep recovery (MSCR) test, temperature scanning and frequency scanning tests were carried out by using dynamic shear rheometer (DSR), and the high temperature performance, temperature sensitivity and viscoelastic characteristics of each asphalt binder sample before and after aging were studied. Finally, the surface free energy theory was used to evaluate the adhesion characteristics of each sample. The results showed that the commonly used foaming agent cetyl trimethyl ammonium bromide has no effect on the foaming of CRA binder. With the increase of CRP content, the foaming temperature became higher, and it was difficult to foam successfully when the rubber powder content was higher than 15%. Increasing the content of CRP in a certain range can improve the high temperature performance and adhesion of foamed CRA binder and reduce its temperature sensitivity. With the aging process of the sample, the high temperature performance of foamed CRA binder increased, and the temperature sensitivity and adhesion characteristics decreased. The surface free energy of foamed CRA binder is mainly composed of dispersion component, and the polarity component is relatively small. The surface free energy of foamed CRA binder increased with the increase of CRP content. In addition, foaming agent B (water-in-oil emulsifier) would reduce the temperature sensitivity and high-temperature performance of foamed CRA binder, but it had no obvious effect on adhesion. • Optimal foaming conditions for rubber asphalt are discussed and the commonly used cetyltrimethylammonium bromide does not enhance its foaming effect. • The amount of crumb rubber powder used has an effect on the rheological properties of the foamed crumb rubber asphalt binder. • Aging reduces the surface free energy of the foamed rubber asphalt binder and reduces its adhesion properties. • The amount of crumb rubber powder mixed affects the surface free energy of the foamed crumb rubber asphalt binder. [ABSTRACT FROM AUTHOR]

In order to further broaden the application scope of basalt fiber reinforced concrete (BFRC), prolong service life in complex environment, master development status and sort out development needs, the durability of BFRC in complex environment was systematically summarized. First of all, the reason and damage mechanism of concrete deterioration in a variety of harsh environment are analyzed and grasped. Secondly, the strengthening mechanism of basalt fiber (BF) structure in permeability, carbonization, sulfate erosion, alkali environment, freeze-thaw cycle and high temperature is reviewed in detail, and the strengthening effect and performance of BFRC are discussed from the perspective of macroscopic properties and microscopic pore structure. The addition of BF reduces the generation and development of early microcracks in concrete structures, promotes the densification of structures on a microscopic scale. What's more, the permeability, carbonation resistance, acid and alkali corrosion resistance, frost resistance and high temperature resistance of concrete structures can be significantly improved. Finally, the problems in the current research are summarized and research ideas to cope with the environmental complexity are proposed to provide a research basis for BFRC to maintain excellent performance in the actual complex application scenarios. This paper focuses on the strengthening effect of basalt fiber on cement-based materials, and mainly introduces its strengthening effect and action mechanism from several aspects in the figure. [Display omitted] [ABSTRACT FROM AUTHOR]

• Inexpensive emulsified asphalt is used in the Self-compacting concrete. • The modification mechanism of EA on the improved mechanical properties of self-compacting concrete was studied. • Laboratory tests show that flexural strength and fatigue performance improved with the EA content. • Suitable EA content is confirmed under the comprehensive consideration of performance and cost. Polymer emulsion is commonly used to prepare the high-performance concrete, including the self-compacting cement concrete (SCC), but the cost obviously increased. One of the alternative emulsions is the inexpensive emulsified asphalt (EA), which has been applied in SCC in recent years. However, the effects of EA on the improved mechanical properties of self-compacting concrete are still unclear. In order to study the mechanical properties of SCC with emulsified asphalt (EASCC), five groups of SCC concrete specimens with different emulsified asphalt content were prepared, and four kinds of tests were performed to evaluate the compressive strength, compressive elastic modulus, flexural strength and fatigue performance. The results revealed that the compressive strength and the elastic modulus of EASCC decrease with the increased poly-cement ratio (PC ratio). On the contrary, the flexural strength and fatigue life of EASCC increased with the incorporation of EA, indicating that the emulsified asphalt can effectively improve the flexural strength and crack resistance of concrete pavement and prolong the pavement service life. And the better toughness performance was achieved when the PC ratio reaches ten percent. To sum up, the EASCC with ten percent content has better performance and more suitable to apply in the pavement under the. [ABSTRACT FROM AUTHOR]