Pipe-soil interaction for segmented buried pipelines subjected to dip faults

This paper describes an investigation of pipe-soil interaction equations suggested by currently used pipeline seismic design codes and the applicability of these equations to segmented pipelines. The results of computer-aided analyses were compared to results obtained in full-scale experiments on a segmented ductile iron pipeline 93mm in diameter and 15m in length. The pipeline was installed 600mm below the ground surface in a sandy soil compacted to two different subgrade reaction values. The type of fault considered was a reverse fault with an intersection angle of 60 degrees with the pipeline, and the fault movement was a total of 350mm in three same steps in the fault trace direction. The findings of this study demonstrate the necessity of considering the nature of soil behavior in pipe-soil interaction equations and the effects of connection joints on the integrated response of pipelines to fault-induced ground deformations. A new combination of equations constituting a direction-wise selection from among the equations proposed by currently used guidelines is introduced as a new series to describe pipe-soil interaction for segmented pipelines and is verified using the results of full-scale experiments. Copyright (c) 2014 John Wiley & Sons, Ltd.