1. Associate Member, ASCE
2. Dept. of Civ. and Envir. Engrg., Georgia Inst. of Technol., Atlanta, GA 30332.
3. School of Civ. Engrg., Purdue Univ., West Lafayette, IN 47907.
4. Prof., School of Civ. Engrg., Purdue Univ., West Lafayette, IN. E-mail: govind@ecn.purdue.edu