1. Research Assistant, Dept. of Civil and Environmental Engineering, Univ. of Washington, Seattle, WA 98195-2700 (corresponding author).
2. Design Engineer, ABKJ Consulting Civil and Structural Engineers, Seattle, WA 98104; formerly, Washington State Dept. of Transportation, Olympia, WA 98504-7300.
3. Assistant Professor, Dept. of Civil and Environmental Engineering, Univ. of Washington, Seattle, WA 98195-2700.
4. Associate Professor, Dept. of Civil and Environmental Engineering, Univ. of Washington, Seattle, WA 98195-2700.