1. Project Engineer, Earth Tech Inc., 200 Indiana Ave., Stevens Point, WI 54481 (corresponding author). E-mail: jian.yang@earthtech.com
2. Associate Professor, Dept. of Civil and Environmental Engineering, Univ. of Wisconsin-Madison, Madison, WI 53706. E-mail: gwharrin@facstaff.wisc.edu
3. Professor, Dept. of Civil and Environmental Engineering, Univ. of Wisconsin-Madison, Madison, Madison WI 53706. E-mail: noguera@engr.wisc.edu