1. Ph.D. Student, School of Civil and Environmental Engineering, Oklahoma State Univ., 207 Engineering South, Stillwater, OK 74074.
2. Associate Professor, School of Civil and Environmental Engineering, Oklahoma State Univ., 207 Engineering South, Stillwater, OK 74074 (corresponding author).
3. Formerly, Graduate Student, School of Civil and Environmental Engineering, Oklahoma State Univ., 207 Engineering South, Stillwater, OK 74078.
4. Research and Development Project Manager, Charles Machines Work, Perry, OK 73077.