Date of Award

2020

Document Type

Open Access Dissertation

Degree Name

Doctor of Philosophy in Civil Engineering (PhD)

Administrative Home Department

Department of Civil and Environmental Engineering

Advisor 1

Zhanping You

Committee Member 1

Jacob Hiller

Committee Member 2

Patricia Heiden

Committee Member 3

Xinfeng Xie

Abstract

The accumulation of waste tires generates severe environmental issues. Using crumb rubber processed from waste tires on the pavement could relieve the pressure of waste tire on the environment and improve the performance of the pavement as well. The application of crumb rubber on the pavement using the dry process was proved to be a cost-effective strategy in some projects, however, the interaction between the rubber and asphalt binder was unknown in the rubber modified asphalt mixture using the dry process, especially when reclaimed asphalt pavement was adopted. The performance improvement of the rubber particle to the asphalt mixture was closely related to the interaction. The influence of aging on the characteristics of rubber modified asphalt mixture using the dry process is critical to its long-term performance. The scope of the dissertation is to evaluate the performance of rubber modified asphalt mixture using a dry process when reclaimed asphalt pavement was adopted. The influence of aging on the characteristics of the rubber modified asphalt mixture and the extracted asphalt binder were investigated.

This dissertation proposed the volumetric design of rubber modified asphalt mixture using the dry process. The aggregate gradation determination, rubber modified asphalt mixture preparation, design binder content determination, and moisture susceptibility evaluation were proposed. The quality control of the laboratory mixture design procedure was critical to guarantee the consistency of the asphalt mixture design in the laboratory and the results of mixture construction in the plant. The high temperature rutting performance and the low temperature cracking performance of plant mixed and laboratory compacted asphalt mixture was evaluated. The influence of various factors, which included mixture design parameters of the asphalt mixture (nominal maximum aggregate size, reclaimed asphalt pavement content, and asphalt content), rubber modification, mixture air void content, test temperature, and aging procedure, on the rutting and low temperature characteristics of asphalt mixtures were evaluated. Based on the evaluation of different assessment parameters, the rubber addition and the rubber addition and aging were the two most critical factors that influenced the rutting and low temperature cracking performance of different asphalt mixtures.

The effect of the Trichloroethylene solvent in asphalt binder was investigated, and the extracted asphalt binder was assessed and compared with the base asphalt binder and rubber modified base asphalt binder. Both the existence of Trichloroethylene and the content of Trichloroethylene had a significant influence on the |G*| of unaged and PAV aged asphalt binder. The Trichloroethylene in the extracted asphalt binder significantly influenced the actual performance of the asphalt binder in the reclaimed asphalt binder, thus potentially compromising the success mixture design. The modified extraction procedure was proposed to improve the accuracy of the extraction procedure. The rubber particles in the asphalt mixture using the dry process were not totally interacted with asphalt binder, only the interacted rubber particles were extracted, and the influence of the interacted rubber particle was assessed. The aged asphalt binder weakened the low temperature performance of the extracted asphalt binder. The aged asphalt binder and rubber in extracted asphalt binder guaranteed the asphalt binder to sustain heavy traffic load, thus improved the permanent deformation resistance of asphalt binder.

Share

COinS