Field Demonstration of Post-Consumer Waste Plastics and Ground Tire Rubber in Columbia, Missouri

MoDOT Project #TR202125Research has shown that asphalt pavements can serve as a destination for some of the major streams of waste materials around the globe, such as scrap tires and plastics. Heightened restrictions imposed by China in terms of waste stream contamination in 2018has catalyzed research on incorporating post-consumer recycled (PCR) plastics into asphalt pavements. On the other hand, Ground tire rubber (GTR) from scrap tires have been used in asphalt pavements since the 1960s, but has not achieved its full potential in terms of market adoption. A field demonstration project is underway in Columbia, MO, to evaluate the incorporation of modern recycled plastic and GTR in asphalt mixtures

The Future of Online Graduate Education in 21st Century Research Universities

Presented on May 26, 2015 at 2:00 p.m. in the Mason Building.William G. Buttlar is a Professor and holds the title of Narbey Khachaturian Endowed Faculty Scholar in the Department of Civil and Environmental Engineering (CEE) at the University of Illinois at Urbana-Champaign. He is also the founder and director of Online and Blended Programs in CEE at Illinois. He also serves on the campus MOOC Review Committee (which oversees Coursera RFP process – Provost appointed), the campus MOOC/Online Strategy Advisory Committee (Provost/Chancellor appointed).Runtime: 71:09 minutesThe nature and demand for graduate and undergraduate education is rapidly evolving. Some fields, such as Civil and Environmental Engineering, are closing in on requiring a Master’s degree or equivalent graduate coursework as a requirement for obtaining licensure to practice in the profession. Employers are looking to universities to provide additional professional or transferable skills to their graduate students, as evidenced by the rise in Professional Science Master’s and other professionally-oriented Master’s programs. Students are looking for ways to reduce or eliminate additional student loan debt as they pursue graduate degrees, and are hungry for opportunities to work while they pursue graduate certificates and degrees. The contemporary student expects to float seamlessly between synchronous and asynchronous learning environments, expects a flexible curriculum allowing interdisciplinary study, and expects teaching technologies and social media to be fully integrated into their collegiate educational and networking experience. These factors suggest that online undergraduate and graduate education will play a pivotal role in the transformation of the 21st century research university. This seminar will provide a case for the development and inclusion of online graduate STEM education at 21st century research universities, and will review lessons learned in developing and deploying ‘traditional’ online and massive open online courses (MOOCs) and programs at the University of Illinois at Urbana-Champaign. Preliminary findings from an ongoing NSF ECR grant will also be presented. Last-but-not-least, a call for collaboration amongst leading research universities in the area of online graduate education will be presented and discussed

Micromechanical modeling approach to predict compressive dynamic moduli of asphalt mixtures using the distinct element method

A clustered distinct element method (DEM) approach is presented as a research tool for modeling asphalt concrete microstructure. The approach involves the processing of high-resolution optical images to create a synthetic, reconstructed mechanical model that appears to capture many important features of the complex morphology of asphalt concrete. Uniaxial compression tests in the laboratory were employed to measure the dynamic modulus of sand mastic (a very fine sand-asphalt mixture) and asphalt mixtures at three temperatures and four loading frequencies. For a coarse mixture considered in this study, it was found that a two-dimensional (2-D) clustered DEM provided good estimates of mixture dynamic modulus across a range of loading temperatures and frequencies without calibration. However, for a fine-grained mixture, the uncalibrated predictions of the 2-D model were found to reside near the lower theoretical bounds and well below experimentally determined moduli, most likely because of current limitations in scanning and modeling resolution and the nature of the 2-D microstructural description. Work is under way to extend the model to three dimensions and to consider linear viscoelastic behavior in the mastic. That notwithstanding, the current modeling approach was successfully implemented in recent follow-up studies to portray bulk material behavior hi conjunction with fracture models to study crack behavior hi hot-mix asphalt

Summary: chapter 5. In: Mechanisms of Cracking and Debonding in Asphalt and Composite Pavements

This chapter presents a summary of the key findings of this state-of-the-art report on the mechanisms of cracking and debonding in asphalt and composite pavements. Some of these key findings have been presented during the 8th Rilem International Conference on Mechanisms of cracking and Debonding in Pavements in Nantes (MCD 2016). It also contains the key recommendations developed by the TG2 group, which produced a RILEM recommendation document as a culminating activity in the final year of the RILEM Technical Committee TC241-MCD. Remaining challenges in the area of asphalt and composite pavement cracking and debonding and recommendations for further study are then summarized

Aggregate effect on asphalt mixture properties by modeling particle-to-particle interaction

A number of researchers have studied aggregate characteristics including elongation, flatness, and other shapes that are believed to affect asphalt mixture properties such as internal resistance, rutting resistance, tensile strength, and complex modulus etc. However, the aggregate modulus also affects the asphalt mixture modulus significantly, which has not been taken into consideration. In this paper, the effect of aggregate particle-to-particle interaction was studied through numerical modeling using the discrete element modeling (DEM) approach. The individual material phases (e.g., aggregates and mastic) were modeled with clusters of discrete elements based upon laboratory testing of the individual phases. For a given set of material parameters for each phase, the degree of particle-to-particle contact in an asphalt mixture was found to have a profound influence on overall mixture modulus. A parametric investigation of aggregate modulus revealed that the contribution of aggregate modulus to overall mixture modulus was very significant. Pending further experimental verification on asphalt mixtures, this finding may shed new light on the importance of aggregate stiffness on overall mixture properties. Copyright ASCE 2007

Distance Technology Transfer Course Content Development

The Illinois Department of Transportation (IDOT) offers multiple technology transfer courses for engineering, project design, and safety training for state and local agency personnel. These courses are often essential to the agency mission. Because of resource constraints, IDOT has been limited in its ability to deliver courses to statewide participants in a timely, standardized, and cost-effective manner. With telecommunications advances and electronic course delivery technologies, universities have developed and implemented multiple methods to effectively deliver highly technical content online to a diverse population of students. Distance course delivery allows individuals to complete courses from almost any geographic location, enabling cost efficiencies and flexible scheduling. The objective of this research was to investigate the efficacy of the development and implementation of online course content for several high-benefit IDOT technology transfer training courses and short courses. This research project assessed learning management system (LMS) options and investigated multiple online methods to deliver course content incorporating Department knowledge and expertise. In addition, this research produced a summary of findings with recommendations for future electronic technology transfer course development efforts at IDOT.Illinois Department of Transportation R27-73published or submitted for publicationnot peer reviewe