1. Postdoctoral Fellow, Dept. of Civil and Environmental Engineering, Rice Univ., 6100 Main St., Houston, TX 77005.
2. Associate Professor and Frank M. Freimann Collegiate Chair in Structural Engineering, Dept. of Civil and Environmental Engineering and Earth Sciences, Univ. of Notre Dame, 156 Fitzpatrick Hall, Notre Dame, IN 46556 (corresponding author).
3. Assistant Professor, Dept. of Civil and Environmental Engineering and Earth Sciences, Univ. of Notre Dame, 156 Fitzpatrick Hall, Notre Dame, IN 46556.