1. NSF Fellow, Doctoral Candidate of Civil and Environmental Engineering, Univ. of Illinois, 205 N. Mathews Ave., Urbana, IL 61801 (corresponding author).
2. Professor of Civil and Environmental Engineering and Diplomate, Geotechnical Engineering, Univ. of Illinois at Urbana-Champaign, 205 N. Mathews Ave., Urbana, IL 61801.
3. Senior Research Engineer, Heritage Research Group, 7901 W. Morris St., Indianapolis, IN 46231.