1. Department of Civil and Environmental Engineering, University of Illinois at Urbana−Champaign, 205 North Matthews Avenue, Urbana, Illinois 61801, United States
2. Department of Materials Science and Engineering, University of Illinois at Urbana−Champaign, 1304 West Green Street, Urbana, Illinois 61801, United States
3. Department of Mechanical Science and Engineering, University of Illinois at Urbana−Champaign, 1206 West Green Street, Urbana, Illinois 61801, United States