Aging Characteristics of Rubber Modified Asphalts in Different Environmental Factors Combinations

Abstract

Two kinds of rubber modified asphalts were investigated and compared with virgin asphalt. In order to get closer to engineering practice, different combinations of four environmental factors were merged into the laboratory aging simulation. Subsequently, conventional property tests, including softening point, viscosity, creep stiffness, creep rate, and fatigue cracking were conducted on asphalt samples. The performance difference of asphalt before and after aging was selected as an evaluation index for asphalt aging degree. The results indicate that two kinds of rubber modified asphalts show stronger resistant ability to temperature deformation and better resistance to traffic loading than virgin asphalt in all kinds of environmental factors combinations. Tests on chemical analyses were conducted to investigate the asphalt aging characteristics. The apparent morphology of rubber modified asphalts are described in detail under an environment scanning electron microscope (ESEM). The damage condition reflected in images reveals the aging degree caused by multiple environmental factors. Moreover, the thermogravimetric analysis (TG) confirms that three kinds of asphalts can maintain thermal stability in various environments. Additionally, new characteristic functional groups were not detected in the infrared (IR) spectra of rubber modified asphalts, which means they have stable antioxidant properties given that their oxidation degrees change slightly throughout the aging processes.

Physical, rheological and microscopic properties of AAT nanomaterial/crumb rubber powder composite-modified asphalt and SBS-modified asphalt

“…Sun and his associates [4,5] conducted a pioneer work in identifying the advantages of nanomaterials in asphalt modification and proved nanomaterial modified asphalt pavement performance in large-scale road test in several freeways. They also conducted a comprehensive and extensive study on nanomaterial modification and nano-composite material modification, on mechanical properties of asphalt mixtures [6][7][8][9][10][11][12][13][14][15][16][17][18]. Nano-montmorillonite with a special layered structure can be used to block contact be-tween the asphalt and the outside to improve the ageing resistance of asphalt materials [19].…”

High Temperature Performance of Rubber-Modified Asphalt Mixtures in Water-Light-Heat Coupled Environment

“…For example, moisture is introduced into the PAV pressure aging vessel through a water addition device to model the combination of long-term aging and moisture damage. simulate the coupling of long-term aging and water damage [7]. However, it is limited by the aging equipment.…”

Laboratory Investigation of Aging Resistance for Rubberized Bitumen Modified by Using Microwave Activation Crumb Rubber and Different Modifiers

“…The incorporation of CR to bitumen transforms rubberized bitumen to a solid–liquid two-phase system at high temperature, which significantly complicates the aging process of bitumen [ 14 , 15 ]. The aging of bitumen, continuous swelling, and the degradation behavior of CR determine the aging process of rubberized bitumen [ 16 ]. Therefore, multiple factors have great influence on the aging resistance of rubberized bitumen such as aging conditions, CR content, CR particle size, and source of base bitumen [ 17 ].…”