1. Research Assistant, Dept. of Civil Engineering, Univ. of Akron, Akron, OH 44325 (corresponding author).
2. Professor, Dept. of Civil Engineering, Univ. of Akron, Akron, OH 44325.
3. Research Aerospace Engineer, National Aeronautics and Space Administration Glenn Research Center, 21000 Brookpark Rd., Cleveland, OH 44135.