A study funded by the Plastics Pipe Institute Inc. (PPI) that evaluated the successful use of corrugated, high-density polyethylene (HDPE) pipe for use under heavy rail car loads with shallow cover, is now available on-line: www.plasticpipe.org/drainage/cppa_technical.html.
The test was conducted by the Transportation Technology Center at the Facility for Accelerated Service Testing (FAST) in Pueblo, CO, where it operates a test bed for railroad track. The methodology of the project included repeatedly running a train consisting of four locomotives with 80 rail cars weighing 315,000 pounds over 48-inch corrugated HDPE pipe with just four-feet of cover from the top of the pipe to the bottom of the rail. In addition, the long-term impact of heavy, static loads on the pipe was assessed by parking the cars, with one set of wheels on the track directly over the same pipe for six weeks. The corrugated HDPE pipe used in the test was manufactured by Advanced Drainage Systems Inc., a PPI-member company.
“The instrumented pipes performed perfectly after 96 million gross tons of heavy axle loading, with measured strains and deflections well below the material limits,” stated Michael Plumier, director of engineering for PPI’s Corrugated Plastic Pipe Division. “The maximum measured combined deflection from construction and dynamic loading was less than 1.5 percent and the maximum deflection due to dynamic loads alone was 0.14 percent. The maximum measured tensile strains were negligible, and the maximum measured compressive strains were less than one percent. Operators noted that track ride quality was acceptable, and no track geometry maintenance was required at the conclusion of the test.”