By: Punyaslok Rath, Joshua E. Love, William G. Buttlar, and Henrique ReisRead More
The usage of Ground Tire Rubber (GTR) in asphalt pavements has gained renewed interest due to its potential sustainability, economic, and performance benefits. This study focuses on asphalt mixtures designed with three different rubber modifier products including (1) a terminal-blend GTR, (2) a dry-process, chemically processed rubber product, and (3) a terminal-blend rubber-polymer hybrid product.
By: Amir H. Alavi , William G. ButtlarRead More
Modern smartphones are equipped with various sensors along with on-board storage, computing and communication capabilities. Owing to these features, they can become an intelligent, scalable, autonomous and potentially cost-free component of the next generation civil infrastructure monitoring systems in future smart cities. Over the past few years, there has been a growing interest in the
By: Behzad Behnia, William G. Buttlar, and Henrique ReisRead More
An acoustic-emission approach to evaluate the low-temperature cracking performance of asphalt binders is presented. The acoustic activity of a thin film of asphalt binder bonded to a granite substrate is monitored while the layer is exposed to decreasing temperatures from around 20°C to approximately −50°C. Results of eight different asphalt binders at three different aging
By: William G. Buttlar, Jim Meister, Behnam Jahangiri, and Hamed MajidifardRead More
A comprehensive lab and field investigation was carried out to evaluate the performance of recycled asphalt mixtures in Missouri by researchers at the University of Missouri-Columbia, in collaboration with the Missouri Department of Transportation and the Midwest Transportation Center. Sixteen field sections were evaluated, including a number of sections from the recent Long-Term Pavement Performance
By: Oliver Giraldo-Londoño, Daniel W. Spring, Glaucio H. Paulino, William G. ButtlarRead More
Rate-dependent fracture processes can be investigated by means of cohesive zone models (CZMs). For instance, one approach enhances existing CZMs with phenomenological expressions used to represent the fracture energy, cohesive strength, and/or maximum crack opening as a function of the crack opening rate. Another approach assumes a viscoelastic CZM in front of the crack tip.