1. Senior Research Scientist, FM Global, Research Division, 1151 Boston-Providence Turnpike, P.O. Box 9102, Norwood, MA 02062 (corresponding author).
2. Associate Professor and Associate Chair for Undergraduate Studies, Dept. of Civil and Environmental Engineering, Northeastern Univ., 427 Snell Engineering Center, 360 Huntington Ave., Boston, MA 02115.