1. Zachry Dept. of Civil Engineering, Texas A&M Univ., 199 Spence St. 501H CE/TTI, College Station, TX 77843, US (Corresponding author), e-mail: kaiwei@e-mail.tamu.edu
2. Ph.D., Texas A&M Transportation Institute, Texas A&M Univ., 199 Spence St. 501B CE/TTI, College Station, TX 77843, US, e-mail: anol@e-mail.tamu.edu