1. Graduate Research Assistant, Dept. of Civil, Environmental, and Architectural Engineering, Univ. of Colorado Boulder, Boulder, CO 80309.
2. Associate Professor, Dept. of Civil, Environmental and Architectural Engineering, Univ. of Colorado Boulder, Boulder, CO 80309 (corresponding author).
3. Research Associate, Dept. of Civil, Environmental, and Architectural Engineering, Univ. of Colorado Boulder, Boulder, CO 80309.