1. Department of Civil and Environmental Engineering, The Pennsylvania State University, 212 Sackett Building, University Park, Pennsylvania 16802, Material Research Institute, The Pennsylvania State University, 199 MRI Building, University Park, Pennsylvania 16802, Neenah Foundry Company, 2121 Brooks Avenue, Neenah, Wisconsin 54956, and Furness-Newburge, Incorporated, 376 Crossfield Drive, Versailles, Kentucky 40383