INSTALLATION OF RAILBED DRAINAGE CASINGS IN EXTREME CONDITIONS UTILIZING THE PIPE RAMMING METHOD

摘要

Water is a powerful force. Drainage culverts direct water away from areas that need protection from erosion. In Ardmore, Oklahoma, the Burlington Northern Santa Fe Railway Company identified three failed drainage culverts that were in dire need of replacement and chose the pipe ramming process to facilitate the replacement with a 95' section of 60" casing at a 2% grade and 2 - 80' sections of 48" casing at a 1 % grade. The pipe ramming process has been successfully used to install steel casing for more than thirty years. When project specifications call for little to no soil displacement, pipe ramming is the cost effective alternative to other methods such as auger boring, open cutting, and micro-tunneling. Open cutting as simply not an option as the rail line could not suspend train activity on the line. The job site was located at the bottom of a 200' rock wall bluff with the tracks between the bluff wall and a river. Access to the site was limited to using the train tracks to get equipment in and out of the jobsite. In addition to these extreme conditions, the casings had to be installed through soil conditions that included rock (2' +/-) and cobble (8" +/-). All this had to be done without stopping the rail traffic that had as many as 56 trains moving through it a day. This paper will discuss the pipe ramming process and challenges related to the installation or replacement of culvert drainage pipes under railroad beds with a special focus on the project completed in Ardmore, Oklahoma for the Burlington Northern Santa Fe Railway Company.