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The properties of asphalt mastic are crucial in determining the moisture sensitivity of asphalt mixtures, but the adhesion performance of the mastic has not been quantitatively described. To address this gap, this study calculated the asphalt mastic surface energy using the equation-of-state method, and established a moisture sensitivity (MS) index based on it. The effectiveness of this index was verified through Marshall testing. First, the surface energy of asphalt and filler was measured, and the critical volume fraction of the mastic was determined using the two-point method. Second, the interaction parameters of asphalt and filler were calculated using the equation-of-state method, and the surface energy of the mastic was obtained. Then the MS index was established to evaluate the moisture sensitivity of asphalt mixtures. This new index utilizes the surface energy and aggregate to quantitatively evaluate adhesion, considering the specific surface area of the aggregate and the thickness of asphalt film. Finally, the MS was validated through Marshall tests of asphalt mixtures. The results demonstrated that the MS obtained by the calculated surface energy exhibits a strong linear correlation with the moisture sensitivity of asphalt mixtures. The goodness of fit reached above 0.90 and the highest was 0.965. This study provided a novel approach to characterize the moisture sensitivity of asphalt mixtures. [ABSTRACT FROM AUTHOR]

Colored asphalt mixtures have recently found extensive applications in roads and public spaces due to their contribution to traffic management as well as aesthetics and landscaping. The development of durable colored asphalts using various materials has been a hot research topic in recent years. Colored asphalt can be developed through the durable colored slurry seal mixture (CSSM) technology. The desired quality of CSSM requires particular attention to the mechanical performance and resistance against crack propagation due to temperature variations and traffic loads. This research aimed at investigating the effect of steel slag (SS) aggregate compared with natural aggregate (NA) on the fracture behavior and performance of CSSM in five different mixtures: NA100% (control sample), SS10%+NA90% , SS20%+NA80% , SS30%+NA70% , and SS40%+NA60%. The performance of CSSM was evaluated using an edge-notched disk bend (ENDB) specimen fracture test at three different temperatures (0°C, −10°C , and −20°C). Additionally, cohesion test, wet track abrasion test, loaded wheel test (LWT)-displacement and LWT-sand adhesion were carried out to further examine the samples. Comparison of the fracture behavior of colored mixtures revealed that the SS40%+NA60% mixture outperformed other mixtures. The results of other performance tests showed that the unique characteristics of SS40%+NA60% mixture improved CSSM performance against vertical displacements, bleeding, cohesion, and moisture sensitivity by approximately 40.2%, 4 7.3%, 28.6%, and 52.7%, respectively. This comprehensive assessment offers valuable insights into the effectiveness of SS as a proper alternative to NA in CSSMs. [ABSTRACT FROM AUTHOR]

This article investigates the impact of Crumb Rubber Modified Bitumen (CRMB) and fibre additives (aramid fibre and basalt fibre) on the performance properties of Stone Matrix Asphalt (SMA) mixtures. Tests were conducted to evaluate mix design, draindown, cantabro loss, moisture sensitivity, rutting resistance and fatigue behavior. The Marshall method, the draindown parameters (ASTM D6390-11) and the cantabro loss characteristics (ASTM D 7064) were used to examine the mix design qualities. The modified Lottman test was used to assess the moisture sensitivity of SMA mixes. The roller compactor cum rut analyzer was used to assess rutting resistance. Findings showed that CRMB and fibre additives effectively controlled binder draindown and minimized abrasion loss in SMA mixtures. SMA-CRMB mixtures had higher draindown, but comparable cantabro loss than SMA-AF and SMA-BF mixtures. Incorporating CRMB and fibre additives enhanced moisture sensitivity, rutting resistance and fatigue behavior. SMA mixtures with 0.3% fibre addition displayed similar performance properties to SMA with CRMB. Further, substituting fibre additions for CRMB in SMA combinations may yield similar performance. [ABSTRACT FROM AUTHOR]

Gelatine adhesives aka 'animal glues' are water-soluble biopolymers used in historic objects such as wooden cabinets and panel paintings since ancient times. This paper investigates the correlations between microstructural features, namely triple helices, and macroscopic properties of four different types of gelatine adhesives, prevalently used in conservation practices, irrespective of the animal origin. These adhesives include bovine bone, bovine skin, rabbit skin, and fish glues. Thin adhesive films were produced via solution casting methods in controlled climate conditions and their thermal and mechanical properties, and moisture sensitivity were investigated. XRD as a non-destructive characterisation method demonstrated good agreement with DSC in the quantification of gelatine adhesive (animal glue) triple helix content irrespective of the animal origin. Linear correlations between triple helices and gel (Bloom) strength and tensile strain energy to failure (toughness) were found for all adhesive types. Dynamic vapour sorption experiments demonstrated that lower triple helix content is correlated with higher moisture sensitivity of the adhesives. Moreover, the effect of environmental RH on the thermal behaviour of adhesives was investigated by DSC. The results demonstrated that the increase in environmental RH causes a reduction in the adhesives' glass transition and denaturation temperatures whilst triple helix content did not alter. Bovine bone glue with the lowest triple helix content showed the least toughness and highest moisture sensitivity, whilst fish glue with the highest triple helix content was identified as the most flexible glue. [ABSTRACT FROM AUTHOR]

The crop drought risk assessment is an important basis for mitigating the effects of drought on crops. The study of drought using crop growth models is an integral part of agricultural drought risk research. The current Decision Support System for Agrotechnology Transfer (DSSAT) model is not sufficiently sensitive to moisture parameters when performing simulations, and most studies that conduct different scenario simulations to assess crop drought vulnerability are based on the site-scale. In this paper, we improved the moisture sensitivity of the Crop Environment Resource Synthesis System (CERES)-Wheat to improve the simulation accuracy of winter wheat under water stress, and then we assessed the drought intensity in the Beijing-Tianjin-Hebei region and constructed a gridded vulnerability curve. The grid vulnerability curves (1 km × 1 km) were quantitatively characterized using key points, and the drought risk distribution and zoning of winter wheat were evaluated under different return periods. The results show that the stress mechanism of coupled water and photosynthetic behavior improved the CERES-Wheat model. The accuracy of the modified model improved in terms of the above-ground biomass and yield compared with that before the modification, with increases of 20.39% and 11.45% in accuracy, respectively. The drought hazard intensity index of winter wheat in the study area from 1970 to 2019 exhibited a trend of high in the southwest and low in the southeast. The range of the multi-year average drought hazard intensity across the region was 0.29–0.61. There were some differences in the shape and characteristic covariates of the drought vulnerability curves among the different sub-zones. In terms of the cumulative loss rates, almost the entire region had a cumulative drought loss rate of 49.00–54.00%. Overall, the drought risk index decreased from west to east and from north to south under different return periods. This quantitative evaluation of the drought hazard intensity index provides a reference for agricultural drought risk evaluation. [ABSTRACT FROM AUTHOR]

In this study, conventional bitumen tests were performed on bituminous binder modified with Cocamide Diethanolamide chemical at different ratios. According to results of tests, the most suitable additive ratio has been determined as 5%. However, it was concluded that indirect tensile strength and resistance to moisture of samples prepared with bituminous binder modified with 5% Cocamide Diethanolamide has been adversely affected. It was desired to investigate that whether these properties could be strengthened by yarn waste fibers. Firstly, the effect of 0.1%, 0.2% and 0.3% yarn waste fibers on samples prepared with reference bituminous binder was investigated. Obtained results showed that both indirect tensile strength and resistance to moisture of samples containing 0.1% yarn waste fiber increased. Therefore, 0.1%, 0.2% and 0.3% yarn waste fibers were added to the aggregate mixture and mixing of them with bituminous binder modified with 5% Cocamide Diethanolamide was provided. According to obtained results, different ratios of yarn waste fibers added to aggregate mixture did not have a positive effect on moisture sensitivity. Tensile strength ratio values of samples containing bituminous binder modified with 5% Cocamide Diethanolamide and yarn waste fibers added to the aggregate mixture did not provide specification limit. [ABSTRACT FROM AUTHOR]

Most available tests of asphalt mixture performance against moisture damage or the effect of additives examined the asphalt mixture's overall performance. Considering the different mechanisms of moisture damage, studying antistripping additives' effect on failure mechanisms might provide a better view of the asphalt mixture's performance against moisture. Accordingly, herein, the effects of various antistripping additives, including a liquid antistripping additive (dodecylamine) and a nano-magnesium hydroxide additive, each at two bitumen weight percentages, with two types of aggregates with different mineralogical properties and a PG 64-16 bitumen on moisture damage mechanism were investigated. The cohesion and adhesion mechanisms of moisture damage were examined using the pull off test, and the asphalt mixture's overall performance was assessed using the indirect tensile strength (ITS) test in multiple dry and wet conditions (1, 2, and 3 freeze-thaw cycles) according to the modified Lottman test. The results revealed that the use of 0.4% dodecylamine and 1% nano-magnesium hydroxide in the mixtures made with lime aggregates increases the tensile strength ratio (TSR) from 62.67% to 85.4% and 84.8%, respectively. In mixtures made with granite aggregates, TSR increased from 54.45% to 72.49% and 71.35%, respectively. The failure mechanisms' assessment showed that the use of 1% nano-magnesium hydroxide in mixtures made with granite aggregate elevated the pull off in the adhesion failure mechanism by 80%, and the pull off increased by 70% in the cohesion failure mechanism. Moreover, the pull off increased by 63% for limestone mixtures in the cohesion failure mechanism and by 56% in the adhesion failure mechanism. The dodecylamine additive with the highest pull off and ITS ratio in all freeze-thaw cycles was more suitable than nano-magnesium hydroxide to promote the asphalt mixtures' overall performance against moisture. The statistical analysis also indicated the significant effect of dodecylamine and nano-magnesium hydroxide additives on asphalt mixtures' moisture sensitivity reduction at a 95% confidence level. The findings show that some additives have a stronger effect on adhesion strength and some effect on cohesion strength, but the additive that better improves the overall asphalt mix performance depends on mix design characteristics and aggregate and bitumen type. [ABSTRACT FROM AUTHOR]

Using modified bitumen has been one of the few reliable methods adopted for improving asphalt performance against moisture sensitivity. This research offers an approach in which both mechanical methods and micro-mechanism investigations have been employed to study the effect of bitumen modified with epoxy resin on the moisture sensitivity of asphalt mixtures. Six bitumen samples: base bitumen and bitumen modified with 1% to 5% epoxy resins, and two types of aggregates (limestone and siliceous) were selected for this study. Surface Free Energy method and Modified Lottman test were used to investigate the moisture sensitivity of asphalt mixtures containing each bitumen-aggregates combination. In the first method, surface free energy values of bitumen and aggregates were estimated and then used in predicting energy parameters related to the moisture sensitivity parameters, using which the changes in adhesion and wetting properties of each bitumen-aggregates mixture were analyzed. In the second method, the indirect tensile strength test was performed on dry and wet asphalt samples, and the tensile strength ratios were obtained for each asphalt mixture, through which the moisture resistance of samples were investigated. Based on the values obtained for the three parameters, it was concluded that epoxy resin addition decreased the moisture sensitivity of asphalt mixtures containing siliceous aggregates by increasing the bitumen and aggregates adhesion as well as increasing the wetting of the aggregates surface with bitumen. Also, in asphalt mixtures containing limestone aggregates, epoxy resin improved moisture sensitivity, but this improvement was only due to increased adhesion between bitumen and aggregates, while the impact of bitumen coating on aggregates surface did not change significantly with the addition of epoxy resin. Among the asphalt mixtures studied, the highest moisture resistance was observed in asphalt mixture containing 4% epoxy resin, at which the Tensile Strength Ratio parameter showed an increase of 11.3% and 21.5% for limestone and siliceous mixtures, respectively, compared to the base asphalt mixture. [ABSTRACT FROM AUTHOR]

The incorporation of waste glass solids, as alternative raw materials, into highway pavements provides excellent benefts such as conserving natural resources, reducing construction costs, lowering environmental pollution, and increasing the accessibility of road aggregates. Since waste glass possesses an all-around fracture, high stifness, and internal friction angle properties, it may improve the quality of asphalt mixtures. Despite these advantages, asphalt mixtures containing glass aggregates, referred to as glasphalt mixtures, sufer from several disadvantages. The poor adhesion between asphalt and glass aggregates leads to stripping and reduces the glasphalt mixture's strength under moisture and vehicle load. Therefore, a suitable additive should be used to solve the glasphalt mixture's moisture sensitivity and improve its mechanical properties. This study investigated the efect of styrene butadiene styrene (SBS) on the mechanical properties and moisture sensitivity of glasphalt mixtures. Five samples with various percentages of SBS copolymer (0%, 2%, 4%, 6%, and 8%) and waste glass particles (10%) were manufactured. The AASHTO T283, Marshall, indirect tensile fatigue, and repeated load axial tests were performed on both modifed and unmodifed samples. The results demonstrated that the use of SBS, with better adhesion between the binder and glass aggregates, reduced the modifed glasphalt mixtures' moisture sensitivity, extended their fatigue life, and enhanced their resistance to permanent deformation compared to control mixtures. [ABSTRACT FROM AUTHOR]

In this work, two commercial no clean fluxes, namely, extremely low residue no-clean flux (NCF) (NC-1) and ordinary NCF (NC-2), were used for the preparation of a fine pitch flip-chip package with a $7.6\,\times \,7.6$ mm2 Si die on a $17\,\times \,17$ mm2 organic substrate. One water-soluble (WS) flux was also used for comparison. Moisture sensitivity of the package was evaluated using JESD22-A113D (30 °C/60% relative humidity (RH), 192 h, $3\times $ reflow at 260 °C). Thermal cycling tests were performed following JESD22-A104D (−65 °C to 150 °C). The high-temperature storage life (HTSL) of the packages was investigated using JESD22-A103C (175 °C). Underfill delamination or voids in the package were investigated by confocal scanning acoustic microscopy (C-SAM). Failure characteristics of the packages were also studied using scanning electron microscopy (SEM). After moisture sensitivity level (MSL) test, vehicles prepared by NC-1 and NC-2 showed failure. SEM images revealed severe delamination between underfill and solder mask in the presence of amine/amide and carboxylic acid-based NCF residue. Solder bump crack were found at < 500 cycles for samples prepared with NC-1 which contains tertiary amine and long carbon chain (C8:C10:C12) carboxylic acid-based. However, failure occurred at < 1500 cycles for NC-2 containing secondary amide and shorter carbon chain length (C3) carboxylic acid. Samples prepared using WS did not show any failure for up to 2000 cycles. Thus, NCF-treated assemblies performed poorly in moisture sensitivity and temperature cycling tests. [ABSTRACT FROM AUTHOR]

Wax is an important factor that affects the durability of asphalt binder. In order to understand the molecular weight distribution and branching of wax on the moisture sensitivity of asphalt binder, pure wax-doped asphalt binders are prepared and the performance of model asphalt binders are evaluated by surface free-energy (SFE) and binder bond strength (BBS) tests. In addition, asphaltene is regarded as an additive in this study. The results show that the addition of eicosane, triacontane, squalane and asphaltene can reduce the moisture sensitivity of asphalt, but not necessarily improve its moisture-induced damage resistance. The physical hardening effect of high-wax asphalt and its model asphalt is stronger than that of the corresponding low-wax asphalt and its model asphalt, and its moisture sensitivity is weaker than that of the low-wax asphalt. For all the model asphalts, there is a good correlation between the cohesion work, cohesion POTS (pull-off tensile strength), POTS ratio (the BBS moisture sensitivity index) and ER (the SFE moisture sensitivity index). When using the BBS test to characterize the moisture sensitivity of high-wax asphalt, it is recommended to leave the sample for some time until it is physically hardened and stable. [ABSTRACT FROM AUTHOR]

In this work, semi-interpenetrated polymer networks (semiIPNs) were developed coupling a supramolecular non-covalent network with a UV-cured one in a poly(dimethylsiloxane) (PDMS)-based elastomer. Ionic driven supramolecular assembly was achieved via acid-base proton transfer reaction by blending amine groups, belonging to the side chains of the PDMS-based polymer, and acidic groups, coming from methacrylic acid. Additionally, the C C double bonds were UV-cured, leading to the formation of the final semiIPNs. Multiple formulations were developed by varying the ionic bond density, namely the amine protonation degree, to study the correlation between the polymer structure and the rheological and self-healing properties. Flow curve analyses confirmed the formation of efficient ionic assemblies upon blending, showing an increase of the Newtonian viscosity of the blends at 25 °C as the ionic bond density increased. Moreover, Fourier-transform infrared spectroscopy evidenced the appearance of the peaks associated to the ammonium carboxylate ions, supporting the achievement of the supramolecular network. Particular attention was given to the study of the effect of environmental moisture on the semiIPNs properties, which was found to highly influence the rheological, the mechanical and the self-healing properties. [Display omitted] • Supramolecular and UV-cured semi-interpenetrated polymer networks are presented. • These semiIPNs are characterized by different ionic bond densities. • These semiIPNs exhibit moisture-sensitive viscoelastic and self-healing properties. [ABSTRACT FROM AUTHOR]

One of the most frequently applied materials in cold weather is deicer, which is utilized to maintain winter roads. The effect of various deicers on moisture sensitivity has been explored by researchers in the asphalt industry; however, their effect on thermodynamic parameters and fatigue behavior of asphalt has rarely been studied. In this study, the effect of NaCl, potassium acetate, and calcium magnesium acetate deicers on fatigue and moisture performances of asphalt was explored using nano hydrated lime. Two prediction models of fatigue life ratio (NfR) and tensile strength ratio (TSR) were presented using genetic programming and group method of data handling to obtain optimal nano hydrated lime content. Finally, according to the results of deicer-forming minerals, two new optimal deicers were obtained, and their effect on TSR and NfR was compared with the three above-mentioned deicers. Results showed that TSR and NfR of calcium magnesium acetate saturated samples were higher than those of NaCl and potassium acetate saturated samples. Moreover, by modifying the properties of bitumen with nano hydrated lime, adhesion free energy, cohesion free energy, and debonding energy amounts increased, which indicates an increase in locking between aggregates and bitumen. By determining the minerals that make up deicers using the energy-dispersive X-ray test, two new deicer compounds were made that had better performance over NaCl and potassium acetate. By optimizing additive percentage in genetic programming method (due to higher accuracy), 1.05% nano hydrated lime was proposed as the best optimal amount for the new optimal deicer to simultaneously increase TSR and NfR. [ABSTRACT FROM AUTHOR]

Background: Soil CO2 efflux is considered to mainly derive from biotic activities, while potential contribution of abiotic processes has been mostly neglected especially in productive ecosystems with highly active soil biota. We collected a subtropical forest soil to sterilize for incubation under different temperature (20 and 30 °C) and moisture regimes (30%, 60 and 90% of water holding capacity), aiming to quantify contribution of abiotic and biotic soil CO2 emission under changing environment scenarios. Main findings: Results showed that abiotic processes accounted for a considerable proportion (15.6−60.0%) of CO2 emission in such a biologically active soil under different temperature and moisture conditions, and the abiotic soil CO2 emission was very likely to derive from degradation of soil organic carbon via thermal degradation and oxidation of reactive oxygen species. Furthermore, compared with biotically driving decomposition processes, abiotic soil CO2 emission was less sensitive to changes in temperature and moisture, causing reductions in proportion of the abiotic to total soil CO2 emission as temperature and moisture increased. Conclusions: These observations highlight that abiotic soil CO2 emission is unneglectable even in productive ecosystems with high biological activities, and different responses of the abiotic and biotic processes to environmental changes could increase the uncertainty in predicting carbon cycling. [ABSTRACT FROM AUTHOR]

Moisture damage is a critical problem of asphalt pavements. Some factors affecting the moisture sensitivity of asphalt mixtures include bitumen properties, air void content, and the type of anti-stripping additive. This study investigated the use of nano-silica for improving the properties of different bitumens and to increase the moisture resistance of asphalt mixtures at different traffic loading conditions. Two types of bitumen (60-70 and 85-100 pen grade) were modified with various percentages of nano-silica (0, 0.2, 0.4, 0.7, and 0.9% by the weight of the bitumen), and physical and rheological tests were conducted to determine the optimum nano-content. Then, the optimal content was used to prepare asphalt mixtures at three different air void contents (4, 5, and 6%) to simulate the heavy, medium, and low traffic loading conditions. Indirect tensile strength (ITS) and compressive strength tests were performed on the specimens in dry and wet conditions, and the effect of air void content and the type of bitumen on the moisture sensitivity and compressive strength of unmodified and nano-silica-modified asphalt concrete was investigated. The results showed that nano-silica improved the moisture sensitivity of asphalt mixtures with 60-70 and 85-100 pen grade bitumens at all air void contents and the effect of nano-silica was higher on the moisture sensitivity of asphalt mixtures with 60-70 than 85-100 pen grade bitumen. [ABSTRACT FROM AUTHOR]

• Study found how multiple factors influence asphalt mixture's pore characteristics evolution. • Explored mesoscopic pore characteristics and macro mechanical strength correlation. • Built on AASHTO T283 and JTG E20-2011, proposed mesoscopic moisture-sensitivity method for asphalt. This paper explored the mesoscopic pore characteristics of asphalt mixtures by considering the coupling effects of grading segregation, dynamic pore water, and salt erosion, utilizing CT scanning technology. The study yielded the following key findings: 1) Under the coupling effects of grading segregation, dynamic pore water, and salt erosion, the sample with heavy segregation of coarse aggregate (HC) exhibited the highest variation in porosity, followed by the sample without gradation segregation (D), while the sample with heavy segregation of fine aggregate (HF) showed the least change. 2)The influence of gradation segregation on different mesoscopic pore characteristics demonstrated significant dispersion before and after the coupling effects of multiple factors. 3)From a mesoscopic scale perspective, this paper proposes a method to assess moisture sensitivity. The results obtained through this method indicate that the coordination number (CN) exhibits significantly stronger moisture sensitivity compared to other mesoscopic pore parameters. [ABSTRACT FROM AUTHOR]

Moisture damage induced by dynamic pore water pressure commonly occurs in asphalt pavement with a service environment of frequent contact with liquid water. Dynamic water environment exhibits a different mechanism of moisture damage comparing with traditional static water immersion and freeze-thaw. The influencing factors of dynamic water environment mainly include the magnitude of pore water pressure, water temperature, and conditioning duration. This paper presents a study on evaluating and quantifying these factors' degree of influence on moisture sensitivity of asphalt mixture using the orthogonal test and the gray correlation analysis method. A new method for moisture sensitivity evaluation was thus proposed based on dynamic water environment conditioning and uniaxial penetration strength test. Finally, the influence of materials' properties on moisture sensitivity were further investigated. The results indicated that the ranking of factors impacting the indicator of fracture work density was water temperature, followed by pore water pressure and conditioning duration. A representative parameter combination of 60?, 0.345 MPa, and 4000 cycles was thus recommended. It was found that dynamic water environment was harsher than static water immersion and almost equal to and even harsher than freeze-thaw. The indicator of fracture work density ratio, which took deformation feature of asphalt mixture into account, could well assess moisture sensitivity. Retained mechanical performance of water-conditioned asphalt mixture decreased with the increase of air void content. SBS modified asphalt binder significantly improved the resistance to moisture damage for asphalt mixture. [ABSTRACT FROM AUTHOR]

Addition of reactants under an inert atmosphere is a fundamental but extremely important technique in synthetic chemistry. Although this is achievable in many cases by using a glove box or a Schlenk-and-syringe technique, the direct addition of powder (solid) materials without contamination by air or moisture has been difficult, especially in the later stages of a reaction. Here, we offer a simple and small apparatus to realize powder addition with easy handling. Use of this apparatus permitted one-pot glycosylation reactions that required extremely dry conditions to be performed in a highly reproducible manner. [ABSTRACT FROM AUTHOR]

• The effects of using two waste materials (ACP and GTR) in hot mix asphalt are investigated. • Laboratory performance tests and statistical analysis are presented and discussed. • Amorphous carbon powder increases the moisture resistance of rubber asphalt mixtures. • Asphalt mixtures containing GTR and ACP have high rutting and fatigue resistance. In recent years, the significant importance of solid waste management, increase in the cost of bitumen and polymer modifiers have encouraged the pavement engineers to use reusable alternative sources. Ground tire rubber (GTR) and amorphous carbon powder (ACP) are considered as two industrial waste which their using in asphalt mixture prevents their releasing in the environment. This study aims to analyze moisture sensitivity, fatigue performance, and rutting resistance of asphalt mixture influenced by using GTR (8, 12, and 16% of bitumen weight) as the modifier of bitumen properties, and ACP (25, 50, and 75% of filler weight) as filler. The results of this study shows that the ACP increases the resilient modulus and indirect tensile strength of rubberized asphalt concrete (RAC) mixtures. The results revealed that despite the negative effect of GTR on the moisture resistance of asphalt mixture, ACP improves the moisture performance. The results of fracture energy also implies that using ACP decreases the fracture energy, but using the GTR improves the fatigue resistance of asphalt mixture. Furthermore, the results of dynamic creep and wheel track tests indicates that 16GTR + 50ACP has the lowest permanent deformation and highest rutting resistance. The results of ANOVA analysis demonstrates that using GTR and ACP has a considerable effect on the performance properties of asphalt mixture. Finally, the results of this study illustrate the simultaneous use cleaner production and wasted materials decreases the environmental damages in addition to improvement of physical properties of the asphalt mixture. [ABSTRACT FROM AUTHOR]

• 0.1% of Zycotherm has the most decrease in dry ITS followed by 0.12, 0.08 and 0%. • Zycotherm has not significant effect on fatigue life of rubberized asphalt. • Zycotherm has not significant effect on rutting resistance of rubberized asphalt. The aim of this study is to investigate effect of a liquid Nanomaterial antistripping agent, namely Zycotherm, as asphalt mixture (AM) additive on fatigue life and rutting resistance of rubberized asphalt at intermediate and high temperatures, respectively. With regard to fatigue performance, indirect tensile strength (ITS) and four-point beam fatigue tests were performed at 25 °C on unmodified and 15% rubberized mixtures containing Zycotherm at concentrations of 0.08, 0.1 and 0.12% by weight of total bitumen. Moisture susceptibility was also examined using wet/dry ITS and, for rutting performance, dynamic creep and wheel tracking test were employed. Results of fatigue-related tests indicated that 0.1% Zycotherm content improves fatigue performance of warm mix asphalt the most as a result of increasing fatigue life and dissipated energy along with reduction in ITS. Furthermore, results of performing dynamic creep and wheel tracking tests at 50 °C proved the high potential of Zycotherm at preserving the rutting performance of rubberized asphalt mixtures. [ABSTRACT FROM AUTHOR]

Copper Slag (CS) is a by-product obtained during the matte smelting and refining of copper. It is classified as waste materials and, therefore, is considered as an environmental issue to cope with. It can be effectively used for construction of pavement layers. On the other hand, in order to save energy and reduce the amount of pollutants released during asphalt production, Warm Mix Asphalt (WMA) technology can also be employed. This paper presents the influence of replacing limestone aggregates by copper slag on the performance of warm mix asphalt. Optimal Binder Contents (O.B.C) of asphalt mixes containing CS proportions of 0, 10, 20, 30 and 40% by total weight of aggregate were determined using Marshall procedure. Results of Indirect Tensile Strength, resilient modulus, flow number and wheel tracking tests indicated that 20% CS in WMA enhances resilient modulus, Marshall stability, rutting and cracking resistance the most and has substantial positive effect on moisture susceptibility. [ABSTRACT FROM AUTHOR]

Highlights • ITS of modified asphalt is higher than conventional asphalt. • Model values showed a very good regression with the experimental results. • Performance of HMA modified with silica is improved. • Nano-silica can improve moisture sensitivity of asphalt Mixtures. • Use of nano silica resulted in a significant increase in compressive strength. Abstract The primary objectives of the design and implementation of asphalt pavement on road and road surfaces are to achieve the best performance in different climatic conditions. Asphalt pavement performance depends on the adhesion and bonding of binder and aggregates that the moisture causes it to disappear and it results in bleeding and stripping. Although the moisture susceptibility mechanism is not fully known, factors such as binder properties, aggregates properties, asphalt mixture properties, quality control during congestion, the dynamic effect of traffic load and the type of anti-stripping additive play a significant role in creating a moisture susceptibility and aggravation of failures. In this paper, Group Method of Data Handling (GMDH)-type neural networks have been used for modeling and prediction of moisture susceptibility of nano silica-modified asphalt concrete. To achieve this goal, 5 types of mixtures with different percentage of nano-silica (0, 0.2, 0.4, 0.7 & 0.9%) were prepared and the moisture susceptibility of modified mixtures was evaluated. Results showed that nano-silica can improve the moisture susceptibility of asphalt mixtures. For modeling, the experimental data were divided into train and test sections (70% for training and 30% for testing). The predicted values were compared with those of experimental values in order to estimate the performance of the GMDH-neural network. The model values showed a very good regression with the experimental results. [ABSTRACT FROM AUTHOR]

Road quality is one of the most important factors concerning the safety of transportation. Adequate skid resistance of a road surface allows drivers to maintain effective control on their vehicles and maneuver when necessary to avoid accidents. Using waste glass in asphalt mixtures is advantageous from the point of technical, environmental and economic perspectives. This study focuses on the topic of asphalt containing crushed glass, also known as glasphalt, by evaluating the skid resistance and moisture sensitivity of these mixtures. Therefore, a laboratory method was used, in which two types of continuous gradation of hot mix asphalt were chosen based on the Iranian highway asphalt paving code (Code No. 234). The fine aggregates, up to 15% of the total aggregate content, were replaced with glass particles in three different gradations. Skid resistance was evaluated in a British pendulum tester, moisture sensitivity by modified Lottman test, and resilient modulus in a UTM machine. Specimens with a moisture sensitivity problem were improved by using zycotherm as an anti-stripping agent. It was found that the crushed glass particles improved skid resistance by up to 20%. The moisture sensitivity test showed that some glasphalts were susceptible to stripping issue, which can be solved by using 0.1% zycotherm in terms of bitumen weight. Finally, findings revealed that glass particles improved resilient modulus of specimens. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • PVC and EAFD improved aging resistance, rutting performance, and fatigue behavior of asphalt binder. • PVC and EAFD increased the rutting resistance and decreased the permanent deformation of the asphalt mixtures. • PVC and EAFD modified asphalt mixtures are more resistant to moisture sensitivity. • Using EAFD and PVC in pavement industry, improves the environmental, technical and economical performance. Abstract Considering the increase in the amount of industrial waste in recent years, the reuse of recycled materials has become commonplace in various industries. In the pavement industry, such recycled materials can be used as a modifier of the asphalt mixtures. Electric arc furnace dust (EAFD) and waste polyvinyl chloride (PVC) are two industrial waste materials that are hazardous to the environment. This study aimed to investigate the effect of EAFD and PVC materials on the physical, mechanical, and chemical properties of asphalt binders and mixtures. For this purpose, chemical properties, microstructural characteristics, fatigue life, and rutting resistance of EAFD and PVC modified asphalt binders were studied using FTIR, SEM, LAS, and MSCR tests, respectively. In addition, the effect of PVC and EAFD additives on tensile strength, moisture sensitivity, and rutting performance of asphalt mixtures were evaluated. The results of the FTIR test showed that the addition of EAFD and PVC additives to asphalt binder significantly reduce the carbonyl index of neat asphalt binder and improve the moisture sensitivity and aging resistance of asphalt binders and mixtures. The results of the MSCR test indicated that EAFD and PVC additives reduce asphalt binder strain and subsequently increase rutting resistance, especially at high stress levels. Also, according to the results of the LAS test, adding PVC and EAFD powders to neat asphalt binder increase the fatigue resistance of asphalt binder against micro-crackers at low strain levels. The results of experiments on asphalt mixtures showed that EAFD and PVC additives improve tensile strength, moisture susceptibility, and rutting performance of asphalt mixtures. Overall, the results of this study illustrated that using EAFD and PVC waste materials in pavement industry, not only eliminate environmental problems caused by these materials and reduce the cost of stabilizing them, but also improve the technical performance of asphalt binders and mixtures. [ABSTRACT FROM AUTHOR]

A dielectric moisture meter is described in which moisture content is determined from the phase shift angle between the increments in the total conductivity of the measurement capacitor of the probe of the moisture meter and its reactive component. These increments are produced by introducing sample material into the capacitor. This kind of moisture meter is shown to be insensitive to the mass of the sample, but is quite sensitive to its moisture content. By comparison with other mass-insensitive moisture meters, this meter has a simpler design and has smaller measurement errors because of a reduced number of measurement and computational operations. [ABSTRACT FROM AUTHOR]

Arid and semiarid ecosystems make up approximately 41% of Earth's terrestrial surface and are suggested to regulate the trend and interannual variability of the global terrestrial carbon (C) sink. Biological soil crusts (biocrusts) are common dryland soil surface communities of bryophytes, lichens, and/or cyanobacteria that bind the soil surface together and that may play an important role in regulating the climatic sensitivity of the dryland C cycle. Major uncertainties exist in our understanding of the interacting effects of changing temperature and moisture on CO2 uptake (photosynthesis) and loss (respiration) from biocrust and sub-crust soil, particularly as related to biocrust successional state. Here, we used a mesocosm approach to assess how biocrust successional states related to climate treatments. We subjected bare soil (Bare), early successional lightly pigmented cyanobacterial biocrust (Early), and late successional darkly pigmented moss-lichen biocrust (Late) to either ambient or + 5°C above ambient soil temperature for 84 days. Under ambient temperatures, Late biocrust mesocosms showed frequent net uptake of CO2, whereas Bare soil, Early biocrust, and warmed Late biocrust mesocosms mostly lost CO2 to the atmosphere. The inhibiting effect of warming on CO2 exchange was a result of accelerated drying of biocrust and soil. We used these data to parameterize, via Bayesian methods, a model of ecosystem CO2 fluxes, and evaluated the model with data from an autochamber CO2 system at our field site on the Colorado Plateau in SE Utah. In the context of the field experiment, the data underscore the negative effect of warming on fluxes both biocrust CO2 uptake and loss—which, because biocrusts are a dominant land cover type in this ecosystem, may extend to ecosystem-scale C cycling. [ABSTRACT FROM AUTHOR]

Asphalt mixtures exhibit deterioration in properties due to several factors; one of these factors is the moisture damage. Many kinds of research have focused on this matter in Iraq; however, up to now, the pavement is suffering from moisture failure due to the penetration of surface water. Asphalt concrete is modified in this research by adding anti-stripping agent and polymer to withstand the moisture damage that occurs in the pavements. Key factors to enhance the mixtures to withstand the damages due to moisture are aggregate–binder cohesion and adhesion. Therefore, the aim of this research is to evaluate the effect of the addition of the anti-stripping agent and the polymer on the moisture susceptibility of asphalt concrete mixtures before and after conditioning. Indirect tensile strength test, Marshall test, and double punching shear test are used to satisfy the evaluation of the mixture properties. The anti-stripping agents that are used were WetFix with styrene butadiene styrene (SBS) polymer with different percentages. It is found that the modified asphalt mixture has good mixture properties in terms of Marshall stability, retained Marshall stability, and better resistance of moisture and stripping. It has been found that the addition of 0.5% WetFix and 3% SBS polymer maximizes the properties among other percentages. It is also observed that the mixing technique of modifiers is important to the resulting performance of asphalt mixtures. [ABSTRACT FROM AUTHOR]

The bond strength between bituminous binder and aggregate is fundamental to evaluate the performance and durability of cold bitumen emulsion mixtures (CBEM). The interaction developed at binder-aggregate interface is strongly dependent on the properties of aggregate, residual bitumen and emulsifiers, as well as on the environmental conditions affecting emulsion breaking. When reclaimed asphalt (RA) aggregate is used in the production of CBEM, the adhesion issue becomes more complex because the residual bitumen interacts with the aged bitumen film coating the RA aggregate surface. In this research, the binder bond strength (BBS) test was performed to evaluate the bonding between a bitumen emulsion, a cold mastic prepared using limestone filler and artificial RA substrates produced using two aggregate sources. The moisture sensitivity along with the effect of curing temperature and time on the bond strength development were also evaluated. The results showed good affinity between both cold bitumen emulsion composites and the aged bitumen film coating the RA substrate, also highlighting a reduced moisture sensitivity for most of the tested systems. Moreover, the BBS results allowed to properly discriminate the effect of curing temperature and time on bond strength between the artificial RA aggregate and the cold bitumen emulsion composites. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to present an experimental study to characterize the mechanical behaviour of warm mix asphalt (WMA) mixtures designed with Chilean natural zeolite and different amounts of reclaimed asphalt pavement (RAP) for sustainable pavement construction. Five WMA mixtures were evaluated and compared with one reference hot mix asphalt (HMA). Two WMA mixtures were fabricated with 0.3% and 0.6% w/a natural zeolite; and three WMA mixtures were fabricated with 0.6% w/a natural zeolite and 10%, 20% and 30% RAP content. The binder contents and volumetric properties were obtained according to Chilean standards. The mechanical properties evaluated were stiffness modulus, cracking resistance, moisture sensitivity, resistance to rutting and fatigue behaviour. The results showed that WMA mixtures with natural zeolite can be manufactured at a temperature of 20 °C lower than reference HMA, fulfilling the design specifications. Likewise, recycled asphalt mixtures can be fabricated at a lower temperature using natural zeolite, showing good performance properties to be used for sustainable pavement construction. [ABSTRACT FROM AUTHOR]

The complex and diversified asphalt modification makes it harder for the assessment of testing methods capable of characterizing the performance of different modified asphalt in the presence of water. In this study, three representative test methods addressing the moisture performance of asphalt were evaluated and compared: surface free energy (SFE) test, binder bond strength (BBS) test and Hamburg wheel tracking device (HWTD) test. Results indicate that the HWTD test can be a benchmark test while the BBS test is a screening test in characterizing the moisture performance of various modified asphalt. In addition, the surface energy component obtained from the receding procedure in the Wilhelmy Plate Method correlated better with the adhesion property of asphalt than those based on the advancing procedure did. The various indices obtained from the three tests were classified as suitable or unsuitable indices on the basis of the analysis of specific additives. Furthermore, based on the degree of their improvement in the moisture performance, additives were classified into three grades: (1) the first grade including linear styrene–butadiene–styrene (SBS), branched SBS and gilsonite; (2) the second grade including high-density polyethylene, and polyphosphoric acid; (3) the third grade including asphalt rubber and terminal blend asphalt. Finally, it was found that base binders with shorter-chain structures and lower aromatics contents showed better moisture resistance in the HWTD test. High mobility of base asphalt binder negatively influenced the corresponding mixture’s moisture sensitivity. [ABSTRACT FROM AUTHOR]

Human daily life activities in various industries and agriculture result in increasing a continuous production of waste materials, which cause major environmental problems, consequently. This study examines performance of an asphalt in which modified bitumen is used. Modified bitumen is prepared by adding 3% of waste plastic and 3% of crumb rubber to bitumen. These percentages of waste plastic and crumb rubber were identified as optimum percentages after performing various classic and functional tests. After preparation of asphalt samples using unmodified and modified bitumen, initial asphalt tests including Marshall stability and moisture sensitivity tests as well as functional tests including resilient modulus, dynamic creep, and indirect tensile strength (fatigue) tests were carried out on the samples. The results show improvements in the behavior of modified asphalt with regard to rutting and fatigue cracking. [ABSTRACT FROM AUTHOR]

Sisal fibre is a natural fibre, which runs along the length of sisal leaves, extraction of which yields fibre. These fibres, which are spared from decomposition, may find significant application in pavement engineering. In this study, an attempt has been made to evaluate the application of sisal fibres in improving the behaviour of bituminous mixes. The effects of addition of four different lengths (5, 10, 15 and 20 mm) with four different dosages (0.05, 0.1, 0.2 and 0.3% by weight of aggregate) on stability, flow and air voids in the bituminous concrete mixes were investigated. The optimum bitumen content was obtained for different combinations. To arrive at the optimal dosage of fibre and length, laboratory performance tests such as stiffness modulus, fatigue life and moisture sensitivity were carried out for all the combinations. The fibre length of 15 mm at 0.05% dosage by weight of aggregate with an optimum bitumen content of 5.4% by weight of mix was seen to provide better performance. [ABSTRACT FROM AUTHOR]

This study explores the materials used in the preparation layers of nine paintings from the Danish Golden Age as a first approach to understanding the variation in use of materials in the nineteenth century as well as the potential for their degradation. Paintings on canvas have traditionally been suspected to be particularly sensitive to high moisture levels because of the changing quality of materials in the nineteenth century. The explanations have partly included the mechanisation of production methods and partly a more experimental approach to painting. Additionally, collagen-based glue sizing of the canvas is suspected to respond dimensionally to changes in relative humidity. In this study, pigments, fillers and binding media in the preparation layers of nine paintings by different artists were identified using scanning electron microscopy with energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry. The study shows a relatively low degree of variation in materials used in grounds. Surprisingly, no collagen-based binder was found in any of the nine paintings, suggesting that the canvases were not glue sized. All paintings contained calcium, lead, a drying oil and egg, even though only few contemporary recipes in painter's manuals included egg as an ingredient for preparation layers. These results suggest that the commercial producers of prepared canvas may not have followed the manuals that were written for painters. Egg may have been added in order to increase flexibility and durability of ready primed canvases that were stored and sold in rolls. Moreover, the egg-oil emulsion has the advantage of being more viscous than a pure oil paint and could thus be used without sizing the canvas, rendering the primed canvas less stiff and less responsive to changes in relative humidity. The advantages of using egg in the ground are obvious, and this use, as well as the lack of glue size, has implications for the long-term preservation of the paintings in changing environmental conditions. These results imply that these particular paintings might be less sensitive to relative humidity changes than expected due to the lack of hygroscopic glue. [ABSTRACT FROM AUTHOR]

This study focuses on the performance analysis of mine roof rock due to moisture variation using a case study, which experienced roof falls. The roof layer types, thicknesses, and properties were determined using extensive lab and field data. A novel numerical model is developed using site information and observed field performance to incorporate: (1) the interaction between roof rock unit beddings, (2) the interaction of roof bolts and rock units, and (3) the effect of moisture increase on roof deformation and failure. Using the proposed methodology, the mine roof layers’ allowable maximum moisture contents prior to failure can be estimated. [ABSTRACT FROM AUTHOR]

Present study deals with applying surface free energy theory in evaluating the possibility of using date seed ash as a bitumen modifier of hot mix asphalt mixtures against moisture damage. For this purpose, pure bitumen as well as ash containing samples was employed to produce mixtures having two different aggregate types (namely, limestone and siliceous). Prediction of surface energy was well supported by the laboratory method (AASHTO T-283) and proves the potential use of ash as a modifier. The achieved results indicated that using date seed ash will improve TSR of limestone and siliceous mixtures (i.e. 12.65% and 20%, respectively). [ABSTRACT FROM AUTHOR]

Extratropical extreme precipitation events are usually associated with large-scale flow disturbances, strong ascent, and large latent heat release. The causal relationships between these factors are often not obvious, however, the roles of different physical processes in producing the extreme precipitation event can be difficult to disentangle. Here we examine the large-scale forcings and convective heating feedback in the precipitation events, which caused the 2010 Pakistan flood within the Column Quasi-Geostrophic framework. A cloud-revolving model (CRM) is forced with large-scale forcings (other than large-scale vertical motion) computed from the quasi-geostrophic omega equation using input data from a reanalysis data set, and the large-scale vertical motion is diagnosed interactively with the simulated convection. Numerical results show that the positive feedback of convective heating to large-scale dynamics is essential in amplifying the precipitation intensity to the observed values. Orographic lifting is the most important dynamic forcing in both events, while differential potential vorticity advection also contributes to the triggering of the first event. Horizontal moisture advection modulates the extreme events mainly by setting the environmental humidity, which modulates the amplitude of the convection's response to the dynamic forcings. When the CRM is replaced by either a single-column model (SCM) with parameterized convection or a dry model with a reduced effective static stability, the model results show substantial discrepancies compared with reanalysis data. The reasons for these discrepancies are examined, and the implications for global models and theoretical models are discussed. [ABSTRACT FROM AUTHOR]

The Hamburg Wheel-Track Device (HWTD) test has recently gained popularity among many state highway departments of transportation (DOTs) for use in hot mix asphalt (HMA) moisture sensitivity evaluation. In this paper, suggestions are presented to improve and provide more consistent and representative results for this test as described in AASHTO T 324 – Hamburg Wheel-Track Testing of Compacted Hot Mix Asphalt (HMA). In the AASHTO T 324 specification, either a cylindrical or a slab specimen can be tested. Use of a two-dimensional micromechanics finite element (2D-MMFE) analysis has demonstrated significant gap/bonding and specimen shape effects on HWTD test results for the cylindrical specimen setup. In addition, the analysis suggests the best method for defining the “rut depth” to ensure consistent results between two specimen setups. Results of this study have concluded that: (1) slab specimens can provide more reliable test results due to larger size and uniform geometry; (2) two cylindrical specimens (cores) should be glued together to prevent localized failure due to larger peak maximum principal strains when there is no bonding; (3) measurements of average rut depth should be collected from stations near the centers of cylindrical specimens to keep the specimen shape effects to the lowest possible level; and, (4) an agency should not allow both specimen setups to be used interchangeably in the HWTD specifications. The investigation also suggests that the average rut depth evolution curve fitted using a three-stage Weibull approach can define the number of passes to failure and define the stripping initiation point ( SIP ) better than the visually determined SIP . [ABSTRACT FROM AUTHOR]

• Bitumen aging increased the moisture sensitivity of asphalt mixture. • The NHL had a better performance in raising the specimens' TSR. • Long-term aging of bitumens increased their free energy of cohesion. • Long-term aging to the bitumens generally increased their cohesion free energy. • Long-term aging to the bitumens generally decreased their adhesion free energy. WMA due to its softer structure and high content of oils is more exposed to aging. Herein, the behavior of WMA in two states of control (unaged) and long-term aging in different compositions was examined and compared. The effect of factors contributing to WMA moisture sensitivity was minimized by utilizing suitable additives. Thermodynamic and mechanical approaches were adopted for this purpose. Two types of aggregates (granite and limestone) and bitumens (PG 58-22 and PG 64-16) were modified with nano-hydrated lime (NHL) and nano-calcium carbonate (NCC). The application of long-term aging increased the cohesion strength of both types of bitumen. Bitumen modification with the additives reduced the bitumen-aggregate debonding energy in the presence of water in control and long-term-aged specimens, which indicated the improved moisture damage resistance of the asphalt mixes By fitting the long-term aging results, the correlation coefficients between the indirect tensile strength ratio and free debonding energy increased from 0.6 to 0.7 in the first, and 0.8 to 0.9 in the third and fifth cycles. Thus, increasing the freeze–thaw cycles led to a stiffer bitumen with greater contribution to bearing the applied load, thereby promoting the validity and precision of mechanical and thermodynamic test results. [ABSTRACT FROM AUTHOR]

[Display omitted] • Crumb rubber was used as a modifier to enrich the waste oils. • CR modified rejuvenators could not hurt the cracking resistance of RAP mixtures. • CR modified rejuvenators could not diminish the moisture damage resistance. • CR modified rejuvenators increase the rutting resistance of RAP mixtures. The asphalt mixtures containing Reclaimed Asphalt Pavement (RAP) materials are commonly stiffer than the conventional mixtures, and a rejuvenating agent may be used to maintain their flexibility. However, the use of rejuvenators could decrease the rutting resistance. In this study, to overcome this issue, crumb rubber (CR) was used as a modifier to rectify the effect of rejuvenators on rutting resistance in recycled mixtures. In this manner, two types of waste oils (waste cooking and engine oils) were mixed with CR separately, and the final manufactured materials were used as CR-modified rejuvenators. Then, the CR modified rejuvenators and pure rejuvenators (i.e., waste cooking oil and engine oil) were added to the asphalt mixture containing 25, 50, and 75% RAP materials. The cracking resistance at intermediate temperature, the rutting resistance, and the moisture sensitivity of different samples was evaluated by performing the semi-circular bending, dynamic creep, and moisture sensitivity tests. The results showed that CR-modified rejuvenators remarkably increase the rutting resistance of rejuvenated mixtures without compromising the cracking resistance and moisture sensitivity. Additionally, the statistical analysis indicated that the type of rejuvenators and RAP content are significant variables for cracking resistance, rutting resistance, and moisture sensitivity. [ABSTRACT FROM AUTHOR]

Linear friction welding of wood is a bonding process applied to wood and during which a stiff bond line is formed by the softening and rehardening of wood components to form a composite material composed mainly of wood fibres embedded in a modified lignin matrix. Unfortunately, the bonds tend to spontaneously delaminate or lose their strength when exposed to moist conditions. Some approaches were previously applied to overcome this problem, but so far a suitable solution has not been found. This paper presents results of applying post-welding thermal modification to reduce the moisture sensitivity of welded wood. The experiments included welding of birch wood, thermal modification under superheated steam at atmospheric pressure, internal bond (IB) and tensile-shear strength testing and soaking tests. As supposed, the non-modified reference specimens performed poorly after the seven days soaking test (on average 0.33 MPa IB strength), whereas the thermally modified specimens yielded almost the same IB strength in dry and wet condition (on average e.g. 1.15 and 0.93 MPa, respectively). Such a similar load bearing capacity in very different moisture conditions was previously reported only in the case of paduk wood. Similar to the reduction of IB strength occurred during the soaking test, also delamination was observed more clearly in non-modified reference specimens (e.g. 4 vs. 0 total delaminations after seven days soaking). Therefore, the authors suggest that post-welding thermal modification could provide a suitable bond-stabilisation method against moisture, although the process parameters must be optimised in further research, for instance, to ensure scalability. [ABSTRACT FROM AUTHOR]

A new silane coupling agent was synthesized based on γ-(methacryloyloxy) propyltrimethoxysilane (KH570). The surface of basalt rocks was modified by KH570 and the new silane coupling agent (NSCA), and the interfacial interaction between silane coupling agent and basalt was also studied. Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) analysis showed that the silane coupling agent molecule bound strongly with basalt rocks. Scanning electronic microscopy (SEM) observation showed that a thin layer of coupling agent was formed on the surface of modified basalt. The boiling test and immersion Marshall test confirmed that the moisture sensitivity of basalt modified with the new silane coupling agent increased more significantly than that untreated and treated with KH570. The Retained Marshall Strength of basalt modified with the new coupling agent increased from 71.74% to 87.79% compared with untreated basalt. The results indicated that the new silane coupling agent played an important role in improving the interfacial performance between basalt and asphalt. [ABSTRACT FROM AUTHOR]

Understanding in situ enzyme activities could help clarify the fate of soil organic carbon (SOC), one of the largest uncertainties in predicting future climate. Here, we explored the role of soil temperature and moisture on SOM decomposition by using, for the first time, modelled in situ enzyme activities as a proxy to explain seasonal variation in soil respiration. We measured temperature sensitivities (Q10) of three enzymes (β-glucosidase, xylanase and phenoloxidase) and moisture sensitivity of β-glucosidase from agricultural soils in southwest Germany. Significant seasonal variation was found in potential activities of β-glucosidase, xylanase and phenoloxidase and in Q10 for β-glucosidase and phenoloxidase activities but not for xylanase. We measured moisture sensitivity of β-glucosidase activity at four moisture levels (12%-32%), and fitted a saturation function reflecting increasing substrate limitation due to limited substrate diffusion at low water contents. The moisture response function of β-glucosidase activity remained stable throughout the year. Sensitivity of enzymes to temperature and moisture remains one of the greatest uncertainties in C models. We therefore used the response functions to model temperature-based and temperature and moisture-based in situ enzyme activities to characterize seasonal variation in SOC decomposition. We found temperature to be the main factor controlling in situ enzyme activities. To prove the relevance of our modelling approach, we compared the modelled in situ enzyme activities with soil respiration data measured weekly. Temperature-based in situ enzyme activities explained seasonal variability in soil respiration well, with model efficiencies between 0.35 and 0.78. Fitting an exponential response function to in situ soil temperature explained soil respiration to a lesser extent than our enzyme-based approach. Adding soil moisture as a co-factor improved model efficiencies only partly. Our results demonstrate the potential of this new approach to explain seasonal variation of enzyme related processes. [ABSTRACT FROM AUTHOR]

The Supercell coater was developed as an in-line small batch tablet coater which uses air-fluidization for tablet coating. Coating time is very much reduced, with improved heat and mass transfer. It was hypothesized that the quasi-continuous Supercell coating process was more suitable for the aqueous coating of tablets containing moisture-sensitive drugs. Acetylsalicylic acid (ASA) was used as the model drug in this study. The extent of ASA degradation in Supercell coating was compared against that of tablets coated using the conventional pan coater. Less than 0.3% of ASA was degraded at the end of the coating process using either coater. The extent of ASA degradation was found to be more pronounced during storage. The Supercell coated tablets exhibited comparable or smaller percentage of ASA degradation than the pan coated tablets at the end of a storage period of 6 months under accelerated stability conditions (40 °C/75% RH) and 3 years under ambient conditions (25 °C/50% RH). The extent and rate of ASA degradation during storage were dependent on the processing conditions employed during Supercell coating. Increase in temperature generally led to a reduction in ASA degradation, while increase in spray rate and coating level caused more degradation. Greater extent of ASA degradation was observed on the surface of pan coated tablets compared with Supercell coated tablets due to greater moisture contact and the slower and wetter coating process. Changes to the processing conditions also influenced the residual moisture content (0.55–2.86%) of the tablets. However, no direct correlation between the residual moisture content of the tablets after coating and the extent of ASA degradation during storage was found. [ABSTRACT FROM AUTHOR]

The main objective of this study was to investigate the effects of loading frequency and temperature on the moisture sensitivity of dense-graded polymer-modified asphalt mixtures using the creep curves derived from the dynamic creep tests. For this purpose, 96 Marshall specimens containing siliceous crushed stone aggregate with penetration bitumen, modified with 4.5% of styrene-butadiene-styrene (SBS) polymer modifier, were fabricated and tested at four different loading frequencies, four temperatures, and two moisture conditions, dry and wet, with three replicate specimens for each experimental combination. The results showed that both the variables of loading frequency and temperature had significant effects on the permanent strains of both the dry and wet asphalt mixtures. As loading frequency increased under the dry condition, permanent strain decreased, and among the four temperatures, the highest permanent strain was measured at the lowest loading frequency. On the other hand, as loading frequency increased under the wet condition, permanent strain increased too and among the four temperatures, the highest permanent strain was measured at the highest loading frequency. [ABSTRACT FROM AUTHOR]

Highlights: [•] Moisture sensitivity of HMA under various environmental and traffic conditions were evaluated. [•] Dynamic creep test was performed to compare permanent deformation of dry and wet samples. [•] At 40°C with decreasing frequency, percent of increase in permanent strain was more in wet samples. [•] At 40°C moisture has more detrimental effect on the HMA compared to 5°C. [•] Ratio of creep to resilient modulus can be a good indicator for evaluating moisture susceptibility. [ABSTRACT FROM AUTHOR]

The use of Warm Mix Asphalt (WMA) for the construction of roads around the world is growing rapidly. This paper presents a new organic WMA product that has been recently introduced to the US market, which is Polyethylene (PE) Wax-based WMA additive with crystal controller to increase the low temperature cracking resistance and anti-stripping agent to enhance moisture susceptibility. To determine the optimum dosage rate, the viscosities of the binder with varying amounts of additive were measured. Based on the Asphalt Binder Cracking Device (ABCD) test, it was found that the low-temperature cracking temperature of asphalt binder would not be affected by the amounts of the additive up to 3.0%. The new Polyethylene (PE) Wax-based WMA mixtures with Reclaimed Asphalt Pavement (RAP) materials were also tested using the Hamburg wheel tracking device and the wheel passes were significantly higher with WMA mixtures PG 64-28 binder, Minnesota aggregates and 25% RAP than the ones with 64-22 binder, Iowa aggregates and 10% RAP. The Hamburg test results seemed to be influenced by more on the characteristics of aggregates and RAP materials than the WMA additive. Two in-service roads in Iowa and Minnesota were successfully rehabilitated using the PE Wax-based WMA mixtures. The average void of 3.8-cm (1.5-inch) WMA overlay (9.0%) was higher than that of HMA overlay (7.0%) placed on an urban street in Iowa City. It was partly due to asphalt temperature that was lowered to match the lower aggregate temperature. However, it is interesting to note that the average air void of the cores obtained from the rehabilitation section of the same street using the same WMA was significantly lower (6.0%). In Minnesota's state highway, the average air voids of four WMA and HMA cores for quality control were 5.85% and 5.29%, respectively and those of four other WMA and HMA cores for quality assurance were 6.05% and 6.01%, respectively. The WMA pavements were easier to reach 94% density with fewer passes of a compactor than the HMA. [ABSTRACT FROM AUTHOR]

Porous asphalt (PA) mixtures are designed with a high air void (AV) (i.e., 18~22%) content allowing rainwater to infiltrate into their internal structures. Therefore, PA mixtures are more sensitive to moisture damage than traditional densely graded asphalt mixtures. However, the moisture damage evolution of PA mixtures is still unclear. The objective of this study was to investigate the moisture damage evolution and durability damage evolution of PA mixtures. The indirect tensile test (ITT), ITT fatigue test, and Cantabro loss test were used to evaluate the moisture sensitivity and durability of PA mixtures, and a staged ITT fatigue test was developed to investigate the damage evolutions under dry and wet conditions. Indirect tensile strength (ITS), fatigue life, indirect tensile resilience modulus (E), and durability decreased with the increment of moisture damage and loading cycles. The fatigue life is more sensitive to the moisture damage. The largest decrements in ITS and E were found in the first 3000 loading cycles, and PA mixtures tended to fail when the decrement exceeded 60%. Damage factors based on the ITS and E are proposed to predict the loading history of PA mixtures. The durability damage evolution and damage factors could fit an exponential model under dry conditions. Moisture had a significant influence and an acceleration function on the moisture damage evolution and durability damage evolution of PA mixtures. [ABSTRACT FROM AUTHOR]

• The CFA and BG modification increased binder stiffness. • The CFA and BG modification increased mxiture dynamic modulus. • The CFA and BG modification improved mxiture fatigue resistance. The main purpose of incorporating waste into asphalt binder is due to their excellent properties and low cost as binder modifiers, in contrast to the impracticability of typical binder in the current flexible asphalt pavement by the increase of heavy traffic loads and volumes. The focus of this study is to use coal fly ash (CFA) with bone glue modified asphalt to check the effect of coal fly ash (CFA) towards fatigue resistance and moisture sensitivity. This study combined 60/70 penetration grade binder with optimum percentage of bone glue (10%) and 2%, 4%, 6% and 8% of fly ash. After conducting consistency tests and some mixture tests, it is concluded that fly ash gives superior fatigue life to flexible asphalt pavement and the effect towards moisture sensitivity is slightly good. [ABSTRACT FROM AUTHOR]

[Display omitted] • Copper slag and reclaimed asphalt pavement were used in sustainable asphalt mixtures. • Macrotexture, initial stiffness, fatigue, ITS, ITSR and rutting tests were used. • The use of RAP increases the stiffness of HMAs and CS modifies the phase angle. • Proper use of RAP and CS reduces water damage in asphalt mixtures with RAP. • Proper use of RAP and CS shows improved performance in fatigue and rutting tests. The use of reclaimed asphalt pavement (RAP) in the construction of hot mix asphalt (HMA) pavements is a widely used alternative in the development of sustainable road infrastructure. For this reason, the use of higher RAP contents continues to be a topic of interest. This study evaluated the performance of semi-dense asphalt mixtures incorporating 50% to 70% RAP and 7.5% and 15% copper slag (CS) as partial replacement of aggregate, to determine the influence of CS on the effective increase of RAP in the design of sustainable asphalt mixtures. The mixtures were evaluated using macrotexture, fatigue strengths, water sensitivity, and the Hamburg wheel tracking test. The results show that the use of RAP improves the permanent deformation resistance (RD) and fatigue life of the mixtures, while the mean texture depth (MTD) and indirect tensile strength ratio (ITSR) decrease. The incorporation of CS in the mixtures with RAP improved MTD and ITSR compared to the mixtures including only RAP and allowed higher RAP contents in fatigue and Hamburg wheel tests without showing a negative influence. [ABSTRACT FROM AUTHOR]

• The bonding properties at different aging levels and moisture conditions were evaluated. • The failure patterns between asphalt binder-aggregate in the BBS test were analyzed. • The correlation between the surface energies and failure patterns was investigated. • The new energy parameters were defined considering SFE energies and failure patterns. • Correlations between new energy parameters, bond strength, and SFE were identified. The bonding potential is one of the imperative parameters of the asphalt binder-aggregate compositions and significantly affects the resistance of the asphalt mixtures against moisture damages. The properties of asphalt binder and aggregate have considerable effects on the moisture sensitivity and bond strength of the asphalt binder-aggregate composition. In the present study, the effects of the aging and stiffness of the asphalt binder, aggregate type, and their interactions on the bond strength and moisture susceptibility of the asphalt binder-aggregate systems were evaluated. The binder bond strength (BBS) test with a new approach of analyzing the failure pattern and the surface free energy (SFE) method were carried out to characterize the bond strength and bond energy parameters. The relationship between the bond strength, failure pattern in the BBS test, and SFE properties were presented. The results indicated strong and meaningful correlations between the SFE properties, failure patterns, and bond strength under dry and wet conditions. The meaningful and good correlations between the failure patterns and bond energies under dry and wet conditions demonstrate that the changes in the adhesive and cohesive failures in the asphalt binder-aggregate compositions highly depend on the SFE properties. Besides, according to SFE results and the failure patterns under dry and wet conditions, new energy parameters were introduced to evaluate the bond strength and moisture sensitivity. [ABSTRACT FROM AUTHOR]