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This research addresses the significant challenge posed by early water damage in highway asphalt pavement, a critical concern affecting pavement service performance. To counteract this issue, the utilization of anti-stripping agents in asphalt is explored as a highly effective technical intervention. In this investigation, a carefully selected amine-free additive was employed to modify the asphalt binder. A comprehensive array of physical and rheological tests, covering aspects such as storage stability, penetration, softening point, ductility, elastic recovery, rolling thin-film oven, retained penetration, the ductility of residue, and rotational viscometer assessments, were conducted to examine the multifaceted impact of the anti-stripping agent on the asphalt binder. Additionally, we assessed the asphalt mixture's sensitivity to moisture through Marshall stability tests after conditioning for 40 min and 24 h, followed by an enhanced immersion test and moisture susceptibility measurement. The results reveal a nuanced interplay of chemical and physical mechanisms influencing the behavior of the asphalt binder. Notably, the incorporation of an anti-stripping agent at a concentration of 0.25–0.5% (by weight of asphalt binder) led to a substantial improvement in the tensile strength ratio (TSR) to 94.9%, a noteworthy enhancement compared to the 80.6% observed with virgin asphalt mixture. Furthermore, the retained stability index (RSI) exhibited a remarkable increase to 98.1%, surpassing the 87.6% recorded for virgin asphalt. This study not only provides crucial insights into the intricate dynamics of asphalt binder performance but also emphasizes the pivotal role of anti-stripping agents in augmenting the structural integrity and resilience of asphalt pavement. [ABSTRACT FROM AUTHOR]

This research studied the sustainable utilization of waste ceramic in asphalt mixtures by substituting fine aggregate with treated and untreated waste ceramic produced from construction and demolition activities. To improve its adhesion to the asphalt binder and lower the moisture susceptibility of Superpave asphalt mixes, the waste ceramic was treated with a silane anti-stripping agent. The Marshall quotient (MQ), Marshall stability (MS), indirect tensile strength (ITS), retained Marshall stability (RMS), and tensile strength ratio (TSR) were used to assess the mechanical performance and moisture susceptibility of all mixes. The changes in the chemical composition, synergy, physical state, and microstructure of the studied composites were also investigated using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The results revealed that substituting fine aggregate with 50% silane-treated waste ceramics reduced permanent deformation by 46%. Moreover, integrating silane-treated ceramics reduced asphalt mixture moisture susceptibility, with an RMS value of 87.7% obtained for asphalt containing 75% treated ceramic particles. The application of a silane anti-stripping agent resulted in high adhesion between the ceramic particles and bitumen as well as the production of fewer air voids in the mixes due to the formation of strong CH aromatic linkages, as well as Si-O and Si-O-Si bonds. The possibility of employing waste ceramics in asphalt mixes as a sustainable alternative to virgin aggregates while decreasing environmental impacts and improving resource efficiency is highlighted in this paper. [ABSTRACT FROM AUTHOR]

This research addresses the significant challenge posed by early water damage in highway asphalt pavement, a critical concern affecting pavement service performance. To counteract this issue, the utilization of anti-stripping agents in asphalt is explored as a highly effective technical intervention. In this investigation, a carefully selected amine-free additive was employed to modify the asphalt binder. A comprehensive array of physical and rheological tests, covering aspects such as storage stability, penetration, softening point, ductility, elastic recovery, rolling thin-film oven, retained penetration, the ductility of residue, and rotational viscometer assessments, were conducted to examine the multifaceted impact of the anti-stripping agent on the asphalt binder. Additionally, we assessed the asphalt mixture’s sensitivity to moisture through Marshall stability tests after conditioning for 40 min and 24 h, followed by an enhanced immersion test and moisture susceptibility measurement. The results reveal a nuanced interplay of chemical and physical mechanisms influencing the behavior of the asphalt binder. Notably, the incorporation of an anti-stripping agent at a concentration of 0.25–0.5% (by weight of asphalt binder) led to a substantial improvement in the tensile strength ratio (TSR) to 94.9%, a noteworthy enhancement compared to the 80.6% observed with virgin asphalt mixture. Furthermore, the retained stability index (RSI) exhibited a remarkable increase to 98.1%, surpassing the 87.6% recorded for virgin asphalt. This study not only provides crucial insights into the intricate dynamics of asphalt binder performance but also emphasizes the pivotal role of anti-stripping agents in augmenting the structural integrity and resilience of asphalt pavement.

The modern road network is of the most important requirements of the present life. The filler is regarded as one of its major components, and it has great importance in the mixture. When improving its properties and specifications, the hot mixing properties of the asphalt mix are improved . The results of the tests conducted for this research showed that the addition of 1.5% H.L to the control mixture led to a significant increase in the stability of Marshall and air voids, with a rise in (20.4 and 7%), respectively, with an increase in the optimum asphalt content. Moreover, the increase in the tensile strength ratio (TSR) was at the same rate and amounted to 13.6% when compared to the control mixture. The mixtures containing cement kiln dust also led to an increase in the stability of Marshall and air voids. The most significant increase was when replacing it by 50% (23.5 and 6%), respectively, with an increase in the asphalt content. The ratio of indirect tensile strength to tensile strength when CKD is 25% and 50% increases by (6.4% and 12.3%) respectively. These properties deteriorate when the cement kiln dust content increases or hydrated lime increases.

In this study, it has been attempted to use thermodynamics theories and the surface free energy (SFE) method to evaluate the effect of anti-stripping additives on the asphalt binder cohesion and asphalt binder–aggregate adhesion under dry and wet conditions. Two types of aggregate, granite and limestone, AC 60–70 and two additives (a polar copolymer and an ethylene copolymer with mineral asphalt binder) used are among the materials used in this study. The results indicate that the use of both types of polymer has increased the cohesion of the asphalt binder and reduced failure in the asphalt binder film. The results show that the polar copolymer increases the basic components and decreases acidic component of the asphalt binder surface free energy that increases the adhesion with acidic aggregates that are susceptible to moisture-induced damage. Ethylene copolymer material also increased the asphalt binder surface free energy that strengthens the non-polar asphalt binder–aggregate bonds. Both polymer materials have reduced the separated free energy and increased the adhesion free energy that reduces the desire for the stripping process in the asphalt mixture. The results of mechanical tests also show that the use of polymeric additives has improved the asphalt mixtures strength against moisture-induced damage. [ABSTRACT FROM AUTHOR]

The mechanical performance of epoxy asphalt concrete has been well reported in existing studies. This study investigated the surface characteristics of asphalt concrete, including the permeability, friction coefficient, moisture damage resistance and surface texture. The permeability test, dynamic friction test, Cantabro test, Hamburg test and laser texture scanning test were carried out for such investigations. Test results show that the permeability of the epoxy asphalt concrete was very low, which is desirable for protecting the steel deck. The friction coefficient can satisfy the requirement for steel deck bridge according to the Pendulum Number. However, it was found that the skid resistance could be a concern when the vehicle speed is higher than a certain level according to the dynamic friction test. The results suggested to control the traffic speed when epoxy asphalt concrete is applied as steel bridge pavement. In terms of the raveling and stripping, it was found that the epoxy asphalt mixture has an excellent anti-stripping performance based on the Cantabro test and Hamburg wheel tracking test results. The yield point was not reached after 20,000 loading cycles at 60 °C in the immersed Hamburg wheel tracking test. The mean profile depth of the epoxy asphalt concrete is 0.305 mm, much lower than conventional asphalt concrete indicating a very fine surface texture. [ABSTRACT FROM AUTHOR]

• Effects of ASAs on moisture resistance behavior of mastic was evaluated. • Additive B provided the best moisture resistance followed by additive C and A. • The failure mode of BBS experiment was mainly cohesion failure. • The POTS of specimens containing granite had higher than limestone ones with ASA. Commonly referred to as stripping, moisture sensitivity is described as the stripping of bitumen from the surface of aggregates. This phenomenon occurs when adhesion bonds between asphalt mastics and the surface of aggregates are fractured mainly due to cohesion failures in the asphalt cement. For evaluating the effect of bitumen-aggregates adhesion and also asphalt mastic cohesion, the bitumen bonding strength (BBS) test on wet and dry conditions was implemented, with regard to a few studies in this field. The experimental program for this study consists of using one binder source Flint Hills PG 64-22, three liquid anti stripping additives (ASA), and two aggregate substrate (limestone and granite). This research aimed to examine the effect of various ASA and mineral fillers on moisture failure resistance in asphalt mastic by the use of BBS experiment. The findings indicated that in dry condition, samples with no additive and containing limestone filler had higher pull-off tensile strength (POTS) than those with granite. While, by addition of ASA, all specimens containing granite had higher POTS compared to those with limestone. In addition, the failure of most of the asphalt mastics was cohesive, except asphalt mastics containing granite filler and the one with limestone filler and additive C. [ABSTRACT FROM AUTHOR]

The presented study explores the effects of decreased temperatures utilized in rolling thin-film oven (RTFOT) laboratory short-term ageing of asphalt binders based on 35/50- and 50/70-penetration paving-grade bitumen. Additionally, the effects of three additives used with these binders at different concentrations are evaluated: liquid anti-stripping agent, liquid warm-mix additive, and solid warm-mix additive. The resulting asphalt binders were subjected to basic (penetration at 25 °C, softening point, dynamic viscosity) and functional high-temperature characterization (G*/sin(δ), high critical temperature, non-recoverable creep compliance). It was found that the decreased short-term ageing temperatures may detrimentally impact the high-temperature grade of bituminous binders, but this effect can be mitigated by the use of appropriate additives. What is more, it was found that bituminous binders may respond differently to the aforementioned factors. Based on the results, it is advised that asphalt binders intended for use in warm-mix asphalts should be thoroughly tested to appropriately simulate the mixture production process and its effects. [ABSTRACT FROM AUTHOR]

• A pure case study (tests on loose as well as compacted asphalt mixture) was performed to access moisture sensitivity of asphalt mixture. • Three different type of anti-stripping modifiers and aggregate sources were selected to prepare the asphalt mixture. • Filler and chemical based modifiers were found relatively better than waste plastic modifiers. • Moisture damage index shows a strong correlation between qualitative and quantitative test regime to access moisture damage of asphalt mixtures. The main purpose of this research study was to predict moisture damage probability of asphalt mixtures using pure case study i.e. tests on loose as well as compacted asphalt mixtures. Polymer, chemical, filler-based modifiers and four aggregate sources i.e. calcium carbonate, dolomite, dolerite and granite minerals were selected to ascertain their effect on moisture damage of asphalt mixtures. Laboratory test results of both test regimes were compared to develop moisture damage index. The analysis of test data showed that filler-based modifiers were better anti-stripping followed by chemical-based modifiers. Moreover, granite minerals showed more loss of adhesion due to less polarity, hydrophilic and acidic nature of aggregates. Basic aggregates (calcium carbonate and dolomite) with its hydrophilic nature were relatively better antistripping. This is mainly due to its high polarity to make relatively stronger bond with asphalt binder. Boiling water test was easy to perform and less time consuming while rolling bottle test was found relatively more reliable in comparison with other tests on loose coated asphalt mixture. In compacted asphalt mixtures test regime, although Marshal stability was easy to perform, but Modified Lottman test as well as Hamburg wheel track test were found relatively better to access moisture susceptibility with reasonable confidence level. A pure case study was compromises of qualitative (tests on loose coated asphalt mixture) as well as quantitative (tests on compacted asphalt mixture) to ascertain relative accuracy of each test on moisture damage. [ABSTRACT FROM AUTHOR]