Civil and Environmental Engineering Department, University of California, Berkeley, Berkeley, CA 94720-1710, United States
Department of Geology and Geologic Engineering, Colorado School of Mines, Golden, CO 80401, United States ; Atmospheric, Earth, and Energy Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA 94551-0808, United States
Civil and Environmental Engineering Department, University of California, Berkeley, Berkeley, CA 94720-1710, United States