Analytical Model for the Structural Behavior of Pipelines During Lowering-In

Abstract

Since pipelines experience the largest deformation during lowering-in, structural analysis for this construction sequence should be performed to ensure structural safety. In this study, a new analytical model named the “segmental pipeline model” was developed to predict the structural behavior of the pipeline. This analytical model consists of several segmental elements to represent various boundary and contact conditions. Therefore, the segmental pipeline model can consider the geometric configuration and characteristics of pipelines that appear during lowering-in. Adopting the Euler-Bernoulli beam and two-parameter beam on elastic foundation theory, the new model takes the effect of the soil and axial forces acting on the pipelines into account. This paper compares the displacements, sectional bending moments and shear forces of the pipeline obtained from the analytical model and finite element (FE) analysis, where good agreement was demonstrated. Also, the paper presents three examples to demonstrate the applicability of the analytical model.