PIPELINES AND LATERALLY LOADED PILES IN ELASTOPLASTIC MEDIUM

The uplift behavior of a shallow pipeline embedded in an elastoplastic medium is examined. An analytical solution for a beam on elastoplasti c foundation is developed and a characteristic nondimensional load-dis placement and stress-displacement relationship are presented. An appro ximate three-dimensional (3D) solution is proposed that accounts for e mbedment and breakaway condition behind the pipeline making use of the load-displacement curves developed for rigid anchors by Rowe and Davi s in 1982. A comparison of these results with those obtained by 3D fin ite-element analysis indicates that the simplified solution of a beam on elastoplastic foundation is a practical alternative for analyzing t he uplift behavior of shallow pipelines. The approximate solution is a lso used to compare the behavior of a laterally loaded pile for which no separation or separation between the surrounding soil and the back of the pile is permitted as the load is monotonically increased. The r esults are presented in the form of nondimensional charts that permit hand calculations and rapid verification of structural design of the p ipeline and piles.