In previous research efforts, it has been shown that at elevated temperatures, the wax content in bitumen does not have a significant impact on rutting behaviour of asphaltic mixes. However, presence cause physical hardening effect lower which encourages propagation cracks. Using waxy bitumen, asphalt mixtures tended to exhibit higher fracture temperature. The study implied quality and mixture performance depended many factors, such as precise chemical composition particularly nature wax....

One of the challenges in designing recycled asphalt mixtures with a high amount reclaimed pavement (RAP) is estimating blending degree between RAP binder and added virgin bitumen. The extent crucial because concrete response influenced by final properties. This paper focuses on evaluation interaction bitumen studying microstructures zone atomic force microscopy (AFM). AFM used to probe change microstructural properties from these two. Averaged have been observed thin-film blends pure...

The microstructure and chemical composition of asphalt binders have a significant effect on their rheological properties and, therefore, performance as road paving binders. This study aims to investigate the effects warm-mix (WMA) additives, organic type type, internal structure base crumb rubber modified (CRMA). A set dynamic shear rheometer (DSR) tests was conducted obtain parameters (e.g., complex viscosity, modulus, phase angle) flow activation energy calculated from Arrhenius equation...

Warm mix asphalt (WMA) technology has been increasingly utilised in rubberised pavements to reduce the production and compaction temperatures incidental fumes odours. This study aims investigate high, intermediate low-temperature performance of crumb rubber modified binders containing WMA additives. The asphalt-rubber interactions under various mixing combinations temperature time were investigated through both microscopic mechanical methods obtain optimum procedure. effects additives...

Countermeasures to the aging of bituminous asphalt binders is a highly important topic for service-life extension in field and recycling old pavements into new structures with similar functional requirements as original structure. are usually achieved by applying additives that restore adhesive mechanical properties binder. The commonly termed (asphalt) rejuvenators. This study examined performance two very distinct rejuvenating agents. effectiveness rejuvenators measured comparing...

Past experimental studies show that tire–pavement friction values are related to conditions surrounding the tire such as pavement temperature, ambient contained air and surface characteristics of pavement. For measurements taken in different temperature conditions, road agencies generally apply correction factors. These factors based primarily on experience previous field test have very limited transferability under conditions. This paper frictional behavior tires using finite element...

Bitumen ageing has a significant impact on the mechanical performance of asphalt concrete. This study utilises dynamic tests (frequency sweep, fatigue, and relaxation) to investigate effect viscoelastic characteristics bitumen. As progressed, shift Black diagrams curves towards lower phase angles was observed; at same time shape changed straight line curvature reduced. Interestingly, based standard fatigue analysis criteria, appears have positive bitumen life. Consequently, it occurs that...

“Aging” is the accumulation process of diverse detrimental changes in molecular structures with advancing age. Resistance to aging termed “durability.” Complex systems such as asphalt binder (AB) need be protected against aging. This paper provides a state-of-the-art review antiaging technologies used prohibit or rejuvenate aged asphaltic materials. The kinetics during and group molecules that mainly are affected discussed. latest developments antioxidation rejuvenation presented, well...

Bitumen undergoes ageing, which leads to changes in its chemical and rheological properties, causing it become harder more brittle with time. This study aims compare the effects of different laboratory ageing methods on chemistry rheology three bitumen types: a Pen 40/60, 70/100, polymer-modified (PmB). Four protocols were applied: at room temperature, oven pressure vessel (PAV), rolling thin-film test (RTFOT) combined PAV ageing. The pressure, time studied using dynamic shear tests infrared...

This work presents an experimental program developed to evaluate the effect of epoxy-asphalt binder, used as replacement bitumen, on durability and fatigue life asphalt concrete mix. The use epoxy-type binder tack coat has been explored well thus experiments have conducted quantify epoxy interface strength two-layer samples. Results indicated that mixes had higher tensile than control mixes, increase was noticed with increasing proportionally amount in bitumen. Additionally, four-point...

Oxidative aging is responsible for the irreversible asphalt stiffening and embrittlement leading to pavements of increased susceptibility fatigue thermal cracking. In recent years, various flexible binders have been introduced in industry produce long-life epoxy are among them. Nevertheless, in-depth understanding oxidative mechanism binding systems still needed enable reliable predictions material degradation through service life. this research, compositional rheological changes asphalt,...

Oxidative aging takes place in bituminous materials during the construction and service life of asphalt pavements has a significant effect on their performance. In this study, porous cores were obtained from field test sections each year 2014 to 2017. The evolution properties recovered bitumen with time was investigated. Cyclic indirect tensile tests performed determine changes mechanical behavior due aging. Additionally, extracted 13 mm slices along depth cores. rheological chemical...

The development and finite element (FE) implementation of a stress-dependent elastoviscoplastic constitutive model with damage for asphalt is described. includes elastic, delayed viscoplastic components. strains (and strain rates) each component are additive, whereas they share the same stress (i.e., series model). This formulation was used so that stress-based nonlinearity sensitivity to confinement could be introduced into without affecting behavior elastic A simple continuum mechanics...