1. Asst. Prof., School of Civ. and Environ. Engrg., Georgia Institute of Technology, Atlanta, GA 30332-0355.
2. Prof., Dept. of Civ. and Environ. Engrg., Univ. of Illinois at Urbana-Champaign, Urbana, IL 61801.
3. Prof., Dept. of Civ. and Environ. Engrg., Louisiana State Univ., Baton Rouge, LA 70803.