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Considering the enormous amounts of virgin materials consumed in road construction and rehabilitation, recycling reclaimed asphalt pavement has aroused great interest recently. Among different modifiers, crumb rubber is a waste material that significantly enhances different characteristics of the asphalt binder. This study investigates the bonding strength of asphalt mastic of reclaimed asphalt binder modified by crumb rubber-modified binder. The study also attempts to model the mastic bonding strength and understand its mechanism. Thirty binders with different percentages of crumb rubber and reclaimed asphalt were mixed with two filler types to produce the asphalt mastics. Moreover, the two phases of the binder colloid, gel and liquid phases, created by crumb rubber modification, were separated to evaluate the crumb rubber interaction and its impact on mastic bonding. The pull-off test was used to evaluate the bonding strength of asphalt mastics and binders, while dynamic shear rheometer and Fourier-transformed infrared spectroscopy were used to evaluate the physiochemical and rheological characteristics of the asphalt binders. The results show that crumb rubber and reclaimed asphalt modifications greatly strengthen the mastic bonding. The accretion of carbonyl groups due to the reclaimed asphalt addition and withdrawal of light components due to the crumb rubber interaction improves the stiffness of the liquid phase binder, which is strongly correlated to the mastic bonding strength. Furthermore, despite its role in strengthening the binder stiffness, the crumb rubber particles as fillers no longer affect the mastic bonding, where this role is undermined by the mineral fillers. [Display omitted] • Crumb rubber and reclaimed asphalt pavement binder modifications enhance the mastic bonding strength. • Mastic bond is highly correlated to the binder bond strength. • Crumb rubber interaction with asphalt binder strengthens mastic bond. • Mastic bond increases by increasing the carbonyl intensity. • The incorporation of mineral filler undermines the crumb rubber impact as filler. [ABSTRACT FROM AUTHOR]

Rejuvenating the reclaimed asphalt pavement by crumb rubber modified binder for recycling in new pavements arouses a great interest as a sustainable paving technology that uses waste to recycle waste and hinders resource depletion. By investigating rheological and adhesion/cohesion characteristics of the asphalt binder, this study aims to divine optimal dosages of reclaimed asphalt and crumb rubber that enhance the overall performance of the binder without undermining any feature. Thirty binders produced from two types of virgin binder, two sources of reclaimed asphalt, three dosages of reclaimed asphalt, and two dosages of crumb rubber were prepared and tested. Bonding, rheological, and physiochemical characteristics of binders were investigated using pull-off test, dynamic shear rheometer, and Fourier transformed infrared spectroscopy. The results show that mixing reclaimed asphalt with rubberized asphalt greatly enhances the cohesion strength, rutting resistance, creep resistance, and colloid homogeneity. However, certain reclaimed asphalt and crumb rubber dosages undermine the fatigue cracking resistance. The physiochemical investigation revealed that the crumb rubber chains intensively swell and disintegrate simultaneously during mixing with virgin binder and further mixing with reclaimed asphalt. Through correlation analysis, it was emphasized that the improvement of cohesion strength and rheological characteristics is ascribed to the physiochemical changes caused by crumb rubber interaction and reclaimed asphalt addition. [Display omitted] [ABSTRACT FROM AUTHOR]

During the life cycle of road pavements, transportation agencies spend large funds for maintenance and rehabilitation. Additionally, vehicle operating costs and fuel consumption are extremely associated with the road pavement condition. Moreover, both rehabilitation actions and commuter usage provoke extensive environmental burdens. Thus, many studies investigated the roles of rehabilitation strategies and management systems in exploiting funds judiciously, attenuating user costs, and alleviating environmental burdens. This study summarizes the main findings of the past studies and provides some perspective reviews for compromising the economic and environmental appurtenances provoked during the road pavement life cycle. It is revealed that the management system, rehabilitation strategies, and case context have intertwined and intensive impacts on the provoked economic and environmental burdens. The review is limited to studies published in international journals over the last 20 years. The study fosters only those studies that considered the whole life cycle at the project level. [ABSTRACT FROM AUTHOR]

The number of energy users in the world is growing more significant and more prominent in the current scenario for the automotive sector. About 70% of India's energy depends heavily on non-renewable fossil fuels. The cost and demand for the fuel are incredibly high. Over and above these reasons, environmental pollution is causing great concern. Consequently, many of the present researchers are focusing on finding a renewable fuel that can become an alternative for fossil fuel that is fast depleting. Biodiesels have drawn much attention from the research community because of their natural characteristics and chemical composition. In this manuscript, we have reported the linseed oil, which is effectively used as biodiesel (B20) and pre-heated to decrease the viscosity of the fuel with the aid of heater up to 100°C. The nanoparticle used in this work is titanium dioxide because of its highest oxygen content and easy availability in the market. Different proportions of titanium dioxide nanoparticles are blended (50 ppm, 100 ppm, 150 ppm, and 200 ppm) with pre-heated linseed oil in a coated diesel engine. The coating material used is Partially Stabilized Zirconium and the preferred thickness of 0.5 mm that is achieved with plasma spray techniques guidance. The crown of the piston or the top surface of the piston is coated with Partially Stabilized Zirconium (PSZ). It is observed that pre-heated PLSNP200 linseed oil has shown the enhanced performance and lower emissions when correlated with all the other blends. Pre-heating of Linseed oil and diesel engine (DI) coating has resulted in a 5.2% increase in thermal efficiency. The combination of PLSNP 200 reduces emissions of CO, smoke, and HC by 37.78%, 25%, and 37.92%, respectively. The oxides of nitrogen are elevated drastically by 7.43% when correlated with diesel fuel. The blend PLSNP200 increased the BTE and NOx by 8.11% and 6.53% respectively when compared with PLS20. The PLSNP200 blend HC, CO and Smoke opacity emission is drastically decreased by 33.82 21.05% and 26.57% when compared with the preheated linseed oil B20 (PLS20). Image 1 [ABSTRACT FROM AUTHOR]