1. Graduate Research Student, Dept. of Civil, Architectural and Environmental Engineering, Missouri Univ. of Science and Technology, 1304 Pine St., 201 Pine Bldg., Rolla, MO 65409.
2. Professor, Dept. of Civil, Architectural, and Environmental Engineering, Missouri Univ. of Science and Technology, 305 McNutt Hall, 1400 N. Bishop Ave., Rolla, MO 65409 (corresponding author).