Stability of Embankments Founded on Soft Soil Improved with Deep-Mixing-Method Columns Michael P. Navin Dissertation submitted to the faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy In Civil and Environmental Engineering Dr. G.M. Filz (Chair) Dr. J.M. Duncan Dr. M.S. Gutierrez Dr. R.D. Kriz Dr. M.P. Singh August 1, 2005 Blacksburg, VA Keywords: Numerical analysis, deep mixing, slope stability, ground improvement