1. Engineer, Thurber Engineering Ltd., Suite 190, 550-71 Ave. S.E., Calgary AB, Canada T2H 0S6 (corresponding author).
2. Adjunct Professor, Bituminous Materials Chair, Univ. of Calgary, 2500 University Dr. N.W., Calgary AB, Canada T2N 1N4.
3. Professor, Bituminous Materials Chair, Univ. of Calgary, 2500 University Dr. N.W., Calgary AB, Canada T2N 1N4.