Effect of Short-Term Aging on Asphalt Modified Using Microwave Activation Crumb Rubber

Abstract

Effective approaches are required to be developed to solve the poor compatibility and thermal stability problems of crumb rubber-modified asphalt (CRMA). This study focuses on a method called microwave activation. However, seldom researches pay attention to the properties of MACRMA after aging. The objective of this study was to prepare microwave-activated CRMA (MACRMA) and investigate the performance of asphalt after aging. The samples were subjected to thin-film oven test (TFOT) at different times and temperatures. The effect of heat aging on the properties of MACRMA was evaluated by three indicator tests: viscosity, dynamic shear rheology test (DSR), and repeat creep recovery test (RCRT). The test results indicated that the MACRMA after two aging conditions had noticeably lower performance values (e.g., penetration, ductility) compared to unaged samples, and thus, the need to control temperature and time for mixing and construction was verified to be important. In addition, the G*/sin δ and phase angle values were largely influenced by the TFOT aging temperature and time. The MACRMA’s ability to recover was improved after aging. Compared with the aging temperature, the aging time had a more significant effect on the deformation and recovery ability of MACRMA.

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

“…The rubberized bitumen contained CR with 40-mesh size had a smaller ∆ T 1 compared with the rubberized bitumen contained CR activated by microwave. During the STA at 163 °C, the swelling reaction and degradation of CR will gradually advance [ 36 , 44 ]. Therefore, the main reactions happening in STA can be divided into the aging of bitumen and the swelling and degradation of CR.…”

“…Xiaolong Yang [ 20 ] determined that CR modified by microwave activation had a more efficient swelling reaction than CR. The recoverability of microwave-activated rubberized bitumen was improved after aging [ 36 ]. However, the desulfurization and degradation give rise to the attenuation of CR’s elastic property, which decreased the resistance to fatigue cracking for rubberized bitumen after aging.…”

Low-Temperature Rheological Properties and Microscopic Characterization of Asphalt Rubbers Containing Heterogeneous Crumb Rubbers

“…An increasing number of studies have been carried out on asphalt rubber for use as a road material [ 3 , 4 , 5 ]. Multistress creep recovery and frequency sweep tests were used to determine the rheological properties, i.e., the high-temperature and fatigue properties, of asphalt rubber mixed with a warm agent and a liquid antistripping agent, as well as of SBS (styrene-butadiene-styrene) biorubber asphalt [ 6 , 7 , 8 ].…”

Microscopic Properties of Hydrogen Peroxide Activated Crumb Rubber and Its Influence on the Rheological Properties of Crumb Rubber Modified Asphalt

“…Xu introduced that an activated crumb rubber method using an ultrasonic focusing apparatus could more significantly improve the compatibility between the activated crumb rubber and neat asphalt binder [19]. Recently, microwave irradiation has been used for CRM pre-treatment before blending with an asphalt binder to improve the properties of rubber-asphalt blends in China [20,21]. Many studies have confirmed that higher surface activity and improved compatibility with asphalt due to microwave radiation treatment cleft the surface vulcanization network of the CRM [22].…”