Lateral Buckling of Pipe-in-Pipe Systems under Sleeper-Distributed Buoyancy—A Numerical Investigation

The crude oil in pipelines should remain at high temperature and pressure to satisfy the fluidity requirement of deep-sea transportation consequently lead global buckling pipelines. Uncontrolled is accompanied by pipeline damage leakage; therefore, active control needed. Pipe-in-pipe (PIP) systems have been widely used because protection insulation characteristics outer pipe inner pipe. In this study, sleeper-distributed buoyancy as an method for PIP with initial imperfections. accuracy technique verified comparing finite element model a 3D experimental data. effects density, pipe–soil friction coefficient, imperfection, stiffness ratio pipes, unit interval on performance are also analyzed. critical force lateral displacement studied using analytic solution, relevant calculation formulas obtained provide basis its engineering application.