1. Graduate Engineer, WDP & Associates, Inc., 402 West Seventh St., Austin, TX 78701.
2. Engineer, Architectural Engineers Collaborative, Littlefield Building, 106 East Sixth St., Suite 450, Austin, TX 78701.
3. Assistant Professor, Dept. of Civil, Architectural, and Environmental Engineering, The Univ. of Texas at Austin, 1 University Station C 1748, Austin, TX, 78712 (corresponding author).
4. Joe J. King Chair in Engineering No. 2, Director of the International Center for Aggregates Research, The Univ. of Texas at Austin, 1 University Station C 1755, Austin, TX 78712.