The Microscopic Mechanism and Rheological Properties of SBS-Modified Asphalt with Warm Mixing Fast-Melting

Double bituminous surface treatment (DBST) has been a widely utilized pavement maintenance material due to its capability to restore the surface roughness of existing pavement and provide a layer of protection against weathering, aging, and moisture. However, DBST is highly prone to aggregate loss at an early stage, which is a very common problem experienced by surface treatment. Therefore, to lessen the aggregate loss and prolong the service life of DBST, fiber additive can be incorporated to strengthen the adhesion between the asphalt emulsion and aggregates. This study investigated the performance of glass fiber-reinforced polymer-modified DBST against aggregate loss by conducting laboratory tests using typical DBST as the benchmark of the test results. Four laboratory tests were chosen to represent different loading applications on the surface of the pavement: the bitumen bond strength (BBS) test, the sweep test, the Hamburg wheel-track test (HWT test), and a one-third-scale model mobile load simulator (MMLS3) model. Furthermore, the curing time of the asphalt emulsion was considered in the BBS test and sweep test. Based on all results from the conducted laboratory tests, polymer-modified DBST with glass fiber reinforcement presented an increased resistance to aggregate loss compared with typical DBST. Moreover, it was found that a longer curing time of the asphalt emulsion, whether it was typical or modified, strengthened the surface treatment’s resistance to aggregate loss.

Section: Asphalt Emulsionmentioning

confidence: 99%

Effect of Simultaneous Application of Glass Fiber Reinforcement and Polymer-Modified Asphalt Emulsion on DBST’s Resistance to Aggregate Loss Using Laboratory Investigation

Kim,

Elipse

2024

Research on Fatigue Performance of Fast-Melting SBS/Epoxy Resin Composite-Modified Asphalt

Men,

Li,

Sha

et al. 2024

A high-performance composite modifier ER-SBS-T was prepared through the mixing of epoxy resin with a fast-melting styrene–butadiene–styrene modifier (SBS-T) to enhance material properties. This study evaluated the fatigue characteristics of ER-SBS-T-modified asphalt using a linear amplitude sweep test, and 70# base asphalt, SBS-modified asphalt, and SBS-T-modified asphalt were used as control groups. The fatigue life of ER-SBS-T-modified asphalt was determined according to viscoelastic continuous damage (VECD) theory. The findings indicated that as the ER-SBS-T modifier content increased, both the maximum value and the cumulative damage limit value increased, while the rate of change of decreased. At strain levels of 2.5% and 1%, the fatigue life of the modified asphalt improved with increasing ER-SBS-T content. However, at a strain level of 5%, the modified asphalt exhibited no significant trend in fatigue life across different ER-SBS-T contents. ER-SBS-T-modified asphalt with a modifier content of >10% demonstrated favorable fatigue performance suitable for practical engineering applications.

Fatigue-Healing Performance Analysis of Warm-Mix Rubber Asphalt Mastic Using the Simplified Viscoelastic Continuum Damage Theory

Li,

et al. 2024

As a green and low-carbon road material, warm-mix rubber asphalt (WMRA) has received extensive attention from scholars for its road performance. In the in-depth study of its properties, the fatigue characteristics of WMRA are particularly critical. However, in current studies on asphalt fatigue performance, its self-healing ability is often underestimated or neglected. Furthermore, the simplified viscoelastic continuum damage theory (S-VECD), with its accuracy, speed, and convenience, provides a powerful tool for analyzing asphalt fatigue performance. Therefore, to analyze the fatigue and self-healing performances of WMRA in practical applications, four sample materials were selected in this study: virgin asphalt mastic (VAM), rubber asphalt mastic (RAM), Sasobit rubber asphalt mastic (SRAM), and Evotherm rubber asphalt mastic (ERAM). Subsequently, the samples were subjected to a comprehensive experimental design with frequency sweep tests, linear amplitude sweep tests, and multiple intermittent loading time sweep tests under different aging conditions. The fatigue and self-healing performances of different aging degrees and different types of WMRA were evaluated based on the S-VECD theory. The results show that aging reduces the fatigue and self-healing performances of asphalt mastic to a certain extent, and at a 7% strain, the fatigue life of SRAM after long-term aging is only 30.7% of the life of the unaged sample. The greater the aging degree, the more pronounced the effect. Under different aging levels, the warm-mix agent can significantly improve the fatigue and self-healing performances of rubber asphalt mastic. After undergoing ten fatigue intermittent loading tests, the recovery rate of the complex shear modulus for the long-term aged VAM was 0.65, which is lower than that of SRAM under the same conditions, and the warm mix can further extend the fatigue life of rubber asphalt by improving the self-healing properties of the asphalt. The role of Sasobit in enhancing the fatigue and self-healing performances of rubber asphalt mastic is more significant. This study can provide a theoretical basis for the promotion and application of WMRA pavements and contribute to the sustainable development of road construction.