Pipeline Supported on a Nonuniform Winkler Soil Model

After a buried bell-and-spigot pipeline was installed at a site, an interior survey showed that some of the pipe sections were as much as 450  mm above the intended grade. One proposed explanation for this phenomenon was that the pipe sections were acting like teeter-totters, with one end settling and the other heaving, due to the variable foundation conditions. Later, when a similar pipeline was planned for the same vicinity, analyses were made utilizing a nonuniform Winkler soil model with randomized spring constants. The analyses showed that the calculated settlements were negligibly small; and there was no predicted teeter-totter behavior. Subsequent measurements confirmed the analyses.