EAS PhD Proposal Defense by Mazen Kandil
Abstract:
This dissertation addresses critical challenges in pavement engineering for the Massachusetts Department of Transportation (MassDOT), focusing on improving asphalt pavements’ longevity and safety.
This research evaluates the transition from Superpave4 to Superpave5 mix design methodology to address persistent field compaction challenges. MassDOT requires an in-place density of 95% of the maximum theoretical specific gravity (Gmm), corresponding to 5% air voids. However, Superpave4 mixtures, when placed in the field, typically achieve 6-8% air voids. To address this, MassDOT increased the minimum Voids in the Mineral Aggregate (VMA) requirement by 1% above AASHTO M 323 specifications to raise the effective binder content and improve compactibility, yet contractors continued to struggle meeting the target density. Therefore, Superpave5, which targets 5% air voids in both laboratory and field applications, will be explored as a potential solution. This research will compare 12.5-mm Nominal Maximum Aggregate Size mixtures designed using both methodologies: Superpave4 with 14% and 15% VMA, and Superpave5 with 15% and 16% VMA. The research will utilize the Bailey Method and Distance to Maximum Density Line parameter to shift mix gradations from the traditional Superpave4 mixtures to the Superpave5 mixtures. The study will evaluate the mixtures in terms of compactibility, rutting performance, cracking performance, permeability, and long-term performance prediction using FlexPAVE™ software simulations. Compactibility will be assessed using the Construction Densification Index, Workability Energy Index, and locking point density. Rutting performance will be evaluated through the Hamburg Wheel Tracking Test. Cracking performance will be evaluated using the Indirect Tensile Cracking Test (IDEAL-CT) and the Texas Overlay Test for intermediate-temperature cracking, and the Thermal Stress Restrained Specimen Test (TSRST) for low-temperature cracking. Furthermore, dynamic modulus, cyclic fatigue, and stress sweep rutting tests will be conducted to apply FlexPAVE™ simulations for predicting long-term performance. Results so far have demonstrated that Superpave5 mixtures exhibited significantly improved compactibility and workability while meeting MassDOT's rutting criteria, the Texas Overlay Test results aligned with CTIndex findings, showing inconsistent cracking behavior between mix types, and TSRST results showed no significant differences between mixture types, indicating that binder rheological characteristics influence low-temperature performance rather than mix design methods.
Additionally, this dissertation investigates alternative friction measurement technologies to address the limitations of MassDOT's current Locked Wheel Tester (LWT). The LWT is expensive, labor-intensive, and disruptive to traffic flow. This research compares friction measurements from invasive sensors, non-contact road sensors, the Dynamic Friction Tester, the Ames Laser Texture Scanner, and crowdsourced vehicle data against the LWT standard. Crowdsourced friction data from equipped vehicles traversing roadway sections enables comparison across measurement methodologies, aiming to identify safer, faster, and more cost-effective alternatives for statewide friction monitoring.
Together, these efforts contribute to MassDOT's ongoing initiatives to enhance pavement durability and safety through evidence-based specification development and innovative monitoring technologies.
Advisor: Commonwealth Professor Walaa Mogawer, Department of Civil & Environmental Engineering
Committee members:
- Professor Benjamin Shane Underwood, Civil & Environmental Engineering, N.C State University
- Dr. Raymon Bonaquist, Advanced Asphalt Technologies
- Professor Radhavi Samarakoon, Civil & Environmental Engineering
- Professor Wenzhen Huang, Mechanical Engineering
Note: All EAS Students are encouraged to attend.
UMassD Center of Innovation and Entrepreneurship, Conference Room 3
: Mazen Kandil Research Proposal Defense (Comprehensive Exam) | Meeting-Join | Microsoft Teams
Professor Walaa Mogawer
wmogawer@umassd.edu