STEEL PIPE WRINKLING DUE TO LONGITUDINAL PERMANENT GROUND DEFORMATION

The behavior and design of a straight buried steel pipe subject to per manent ground deformation (PGD) where the movement is parallel to the pipe axis is considered. The PGD zone is characterized by the amount o f movement, delta, and the length or spatial extent, L, of the zone. B ecause of the ability of steel pipe to deform in tension well beyond t he effective yield strain, wrinkling of the pipe wall in compression i s taken as the failure mode of interest. Critical values for delta and L, which result in wrinkling of the pipe wall in compression are dete rmined for five different pipe materials and various burial conditions . In most situations, it is found that the behavior and onset of wrink ling are governed by the length of the PGD zone. The utility of this i nformation is illustrated by a design example.