A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Civil Engineering

Thesis (M.Eng.) - Asian Institute of Technology, 2000

Rubber asphalt is a new highway material that can greatly improve the durability of pavement structure. An investigation is made into a suitable mixture design for pavement applications. First, engineering properties of rubber asphalt material will be examined based on a number of laboratory experiments, leading to a Marshall mix design that observes the behaviors of voids, flow, and stability of the mixture. To study hysteretic behaviors of the rubber asphalt concrete, a triangular low frequency was generated in the controlled-strain and controlled-stress modes. Both modes were tested in compressive condition. In the controlled strain case, the stress history obtained in compressive and tensile paths due to the viscoelastic properties of rubber asphalt concrete and damage was obtained by the reduction of secant pseudo stiffness. In the case of stress mode, the s tress history was generated in compressive direction and the damage growth can be described by the permanent strain in each cycle. In term of durability, the 20% of added rubber is found to be the best mixture that can greatly extend the fatigue life of the pavement. The constitutive modeling of rubber asphalt concrete was obtained in controlled strain mode based on the correspondence principle that allows the evaluation of damage growth and relaxation to be performed separately.