1. Department of Civil Engineering, MingHsin University of Science and Technology, No. 1, Hsin-Hsing Road, Hsin-Fong, Hsin-Chu 304, Taiwan.
2. Material and Pavements Section, Texas Department of Transportation, 4203 Bull Creek Road, Austin, TX 78731.
3. Department of Civil Engineering, National Central University, ChungLi Taoyuan, 320, Taiwan.