Date of Award

Fall 2025

Project Type

Thesis

Program or Major

Civil Engineering

Degree Name

Master of Science

First Advisor

Eshan V. Dave

Second Advisor

Mohamed Elshaer

Abstract

The incorporation of additives in asphalt mixtures is an innovative method of improving the performance of asphalt pavement and promoting economic and environmental sustainability in asphalt pavement construction and maintenance. However, the long-term performance of various additive-modified mixtures under different climatic and traffic conditions, as well as the aging effect of additives, is still being studied. The various types of additives and processes for incorporating additives into asphalt mixtures significantly impact the performance of asphalt pavements modified with additives. This study focused on the low-temperature cracking performance of various additives, including rubber, plastic, and aramid fibers, incorporated into asphalt mixtures through both wet and dry processes. Control mixtures, designed with different traditional asphalt binder grades, such as an unmodified, softer binder, a Superpave 5.0-designed binder, and an SBS-modified binder, were compared to additive-modified mixtures. A suite of tests was conducted on reheated and aged plant-produced and laboratory-compacted mixtures, including the Uniaxial Thermal Stress-Strain Test (UTSST), Complex Modulus, and Disk-Shaped Compact Tension (DC(T)) test. These laboratory tests provide a comprehensive evaluation of the mixtures, obtaining their mechanical and thermal properties. Furthermore, mechanistic-empirical tools such as IlliTC and FlexPAVETM were used to model the thermal cracking and thermal fatigue performance of the mixtures. Results indicate that additive-modified asphalt mixtures have significantly better low-temperature cracking resistance compared to the control mixtures studied. Additionally, some additive-modified mixtures were more susceptible to aging than others, and the methods of incorporating these additives affect their properties. Overall, the findings from this study suggest that additive-modified mixtures have the potential to enhance the long-term low-temperature performance of asphalt pavements.

Download

Share

COinS