Projects

ADOT is interested in evaluating pre- and post-project pavement performance data for ADOT pavement designs. This study would examine recent and new ADOT construction projects and rehabilitation projects to verify the reliability, suitability, and acceptability of the results and recommendations provided by AASHTOWare Pavement ME Design 3.0 software for the performance of rigid and flexible pavements on Arizona’s roads.

The objective of this study is to evaluate the predictive performance results from PaveME compared to the actual pavement performance results on past pavement rehabilitation projects.

Reflective cracking in asphalt concrete (AC) overlays on existing jointed concrete pavements is considered a major pavement distress. The movement of the PCC slabs below the overlay due to the combination of thermal and traffic loading leads to reflective crack growth through the AC overlay.

Sponsored by the Federal Aviation Administration (FAA), Arizona State University, in collaboration with the University of Illinois Urbana-Champaign, is proud to launch the next phase of a groundbreaking project to solve this challenge. Building on our successful initial research, this new initiative will develop state-of-the-art and validated models to predict and joint reflective cracking in AC overlays on rigid airfield pavement structures.

The Arizona Department of Transportation (ADOT) is responsible for building, operating, and maintaining the roads and bridges of the state highway system; the primary source of funding comes from fuel taxes. What are the impacts of heavier and over-dimension/overweight (OD-OW) vehicles on Arizona’s transportation infrastructure compared to other vehicle classes? This research study will identify and document the current impact on Arizona’s roads and bridges by motor vehicles classified in the following three categories: passenger vehicles, commercial vehicles, and OD-OW vehicles. The study will determine the consumption costs (i.e., the costs to build, maintain, and repair the roads and bridges) for each vehicle category.

Arizona Department of Transportation (ADOT) is currently engaged in a research project to assess innovative test methods to predict the cracking resistance of ADOT asphalt mixes across the state. The ADOT Materials Laboratory (Lab) obtained an apparatus known as the IDEAL-RT, which is used to conduct the shear rutting tests that predict the resistance to rutting (permanent deformation) of asphalt mixes. The Lab is interested in this test method to determine if it is acceptable for regular use in future rutting-resistance assessments of ADOT asphalt mixes. To refine its mix designs and improve resistance to cracking and rutting, the Lab needs valid, reliable methods to test and predict asphalt performance. This project will focus on assessing the IDEAL-RT as a tool for predicting rutting resistance. 

Durability cracking in asphalt pavements is a major deterioration mechanism for asphalt concrete (AC) pavements in areas experiencing temperature and precipitation extremes. In this study, we develop a case study example of thermal and durability cracks widely observed in the Southwest of United States. Significant factors and root causes influencing occurrences of thermal durability cracks are presented using data compiled from forensic investigation of sites, field core characterization and mechanistic assessment of the conventional flexible pavement structures.

Field aging of asphalt concrete (AC) mixtures is a complex phenomenon resulting in significant changes in the rheological properties and chemistry of binders and impacting key performance characteristics of asphalt mixtures. Laboratory simulation of the field aging characteristics of asphalt concrete (AC) mixes is essential in characterizing its long-term performance. Hence, long-term aging protocols have become a key part of the Balanced Mix Design (BMD) framework adopted by many state and local agencies.

Although cracking resistance research has been carried out extensively in other states, a large amount of the work is not immediately applicable to Arizona, where the climate is substantially more extreme both in heat and in cold than many other parts of the country.
Main goal of this is to develop a balanced mix design framework that can be used in diverse climatic regions and develop a better understanding of fracture behavior of polymer modified mixes. 

The in-place density of asphalt pavements is a key indicator of construction quality, durability, and long-term performance. Pavement construction requires coordination and monitoring to ensure proper compaction which in-turn achieves the targeted in-place density. Two major factors hindering targeted in-place density are uniform mat temperature and uniform rolling pattern. The objective of this study is to develop an automated monitoring protocol with use of aerial images using uncrewed aerial vehicle (UAV).

Fiber reinforcement is considered to improve the cracking resistance of asphalt concrete (AC). Fibers can delay the crack propagation and improve fracture resistance through various crack bridging mechanisms.
Main goal of this study is to investigate the cracking performance of Fiber Reinforced Asphalt Concrete (FRAC) based on comprehensive fracture characterization performed through a series of monotonic and fatigue fracture type of experiments.


 

Reflective cracking in hot-mix asphalt (HMA) laid over existing jointed concrete airfield and highway pavements is considered as a major pavement distress. Reflective cracking mechanisms are complex due to intertwined effects of temperature and vehicular loading conditions causing intensified stresses in overlays.
The proposed study presents an HMA overlay thickness design model for reflective crack growth.

Automation technology offers numerous advantages to the trucking industry in terms of fuel savings, operational efficiencies and preventing fatal crashes. Truck spacing is one of the key parameters of a truck platoon that can be optimized to balance fuel savings and impact to the pavements. Rest period defining the duration between the loading applications from two consecutive trucks can impact permanent deformations and fatigue cracking in asphalt pavements.
Main challenge with this new type of loading scenario is the uncertainty of the stress state configurations that may be generated during the loading phase of the platoons.