1. Assistant Professor, Dept. of Civil, Environmental, Architectural Engineering, Univ. of Colorado at Boulder, 1111 Engineering Dr. 428, UCB, ECOT 422, Boulder, CO 80309-0428 (corresponding author).
2. Professor, Dept. of Civil, Environmental, Architectural Engineering, Univ. of Colorado at Boulder, 1111 Engineering Dr. 428, UCB, Boulder, CO 80309-0428.