Pretreatment of Crumb Rubber with a Silane Coupling Agent to Improve Asphalt Rubber Performance

Abstract

There are known problems of dissolution, consistency of performance, segregation, and instability with the crumb rubber currently used in asphalt for road engineering. A silane coupling agent (KH550) solution was therefore used to pretreat the crumb rubber so as to improve its interfacial characteristics. The effects of KH550 on the properties of asphalt rubber were studied using high- and low-temperature performance tests, temperature sensitivity test, and compatibility test. On the basis of these tests, the optimum concentration of KH550 pretreated crumb rubber is 1.0%. The surface properties and micromodifications of the treated crumb rubber were analyzed using scanning electron microscopy and an infrared spectrometer. The performance and economic benefit of the modified asphalt rubber was compared to styrene-butadiene-styrene (SBS) modified asphalt, and it was found that KH550 pretreated crumb rubber is able to significantly improve the high-temperature performance of asphalt rubber, thus offering notable potential economic benefits.

Performance evaluation of Asphalt Rubber Gap-graded mixture

“…As the number of vehicles on the road grows, so does the number of tires. According to estimates, around the globe billions of tires are produced each year, the most of which will end up as waste tires (Chen et al, 2020;Liu et al, 2021). To keep up with the increased volume of traffic, asphalt concrete must evolve as well in order to improve the material's resistance to rutting and cracking and also increase its durability (Wiranata & Malik, 2021).…”

“…Ground Tire Rubber (GTR) or Crumb Rubber (CR), which has been utilized in the paving industry since the 1960s, is one way of recycling scrap tires. Since then, it has grown in popularity around the world as a solution to a severe waste management problem and an improvement in asphalt surface performance (Chang et al, 2020;Liu et al, 2021). No matter how much tire composition differs from one manufacturer to another and from one type of vehicle to another, the primary components of all tires are nearly identical.…”

“…Premature rutting and fatigue cracking under repeated stress as a result of mix design and construction flaws are common challenges that AR pavements face. Liu et al (2021) evaluated fatigue resistance. In this study, it has been discovered that the best AR content may be achieved by analyzing the resistance to high temperature and fatigue of gap graded AR mixtures through the use of flow testing, Marshall stability testing, wheel tracking testing and fatigue testing.…”

The Properties of Sodium-Hypochlorite-Activated Crumb Rubber and the Influence of Aging on the Rheological Properties of Activated Asphalt Rubber

“…At the same time, chemical activation has good application prospects because of its high reaction efficiency and low energy consumption. Studies have shown that H 2 O 2 , the silane-coupling agent, and ethylene vinyl acetate can increase the solubility of crumb rubber in asphalt [11][12][13]. Ren [14,15] analyzed the influence of the expansion-degradation degree of crumb rubber in asphalt on the chemical and rheological properties of rubber asphalt, and considered that the degradation of crumb rubber increased the formation of free hydroxide groups.…”