1. Senior Technical Staff Member, Dept. of Structural Engineering, B&W Y-12, Y-12 National Security Complex, P.O. Box 2009 MS8106, Oak Ridge, TN 37831-8106.
2. Associate Professor, Dept. of Civil and Environmental Engineering, Utah State Univ., 4110 Old Main Hill, Logan, UT 84332-4110 (corresponding author).
3. Associate Professor, Dept. of Civil and Environmental Engineering, Utah State Univ., 4110 Old Main Hill, Logan, UT 84332-4110.