Mar 23, 2015 · [1] Federal Highway Administration, “Manual on Use of Self-Propelled Modular Transporters to Remove and Replace Bridges”, U.S. Department of Transportation, June 2007. [2] M.L. Ralls, “Introduction on Use of Self-Propelled Modular Transporters (SPMTs) to Move Bridges”, Real Solution Webinar, National Highway Institute, June 2008.