1. Emeritus Professor, Dept. of Civil and Environmental Engineering, Colorado State Univ., Fort Collins, CO 80523-1372.
2. Graduate Research Assistant, Dept. of Civil and Environmental Engineering, Colorado State Univ., Fort Collins, CO 80523-1372.
3. Associate Professor, Dept. of Architecture, Design and Urban Planning, Faculty of Architecture, Univ. of Sassari, Palazzo del Pou Salit, Piazza Duomo 6, 07041 Alghero, Italy (corresponding author).
4. Assistant Professor, Civil Engineering Technology, Metropolitan State College of Denver, Campus Box 61, P.O. Box 173362, Denver, CO 80217-3362.