Finite element stress analysis of unilaterally supported submarine pipelines

Non-linear finite element simulations of highly curved submarine pipelines

“…The ®rst involves the modelling of pipe laying along shallow strait crossings. 5,6 In this case, since both boundary points are on-shore, the Poisson eect is assumed to be the dominant factor in evaluating pipe deformations during pressurization, resembling the analysis procedures of onland sections. 29 The second type of problem concentrates on deep sea horizontal pipelines.…”

“…The mathematical problem formulation is next complemented by the contact or suspension condition 5,6 of…”

“…If f w and f q are set equal to w and q, respectively, then vector linearization is achieved and as a consequence the seabed±pipeline contact problem is reduced to a standard determination of either the unknown reactions (¯exibility method) or displacements (stiness method) using QP, 1±3 or the pipe elevations and relevant derivatives using SOR. 5 Once an initial pipe pro®le has been computed through the use of linear theory, the load vectors are then re-evaluated and a new random contact problem is solved. Convergence of the non-linear procedure is assumed to be reached when the maximum percentage dierence of the pipeline elevation, between non-linear iterations, falls below a prescribed tolerance limit.…”

“…By considering full soil-pipe contact, Bianchi and Oliveri 4 used a node-by-node negative seabed reaction elimination method for identifying the free pipeline span development along the complete subsea route. With the aid of an SOR algorithm and ®fth-order ®nite elements, Kalliontzis et al 5 examined the static installation bending stresses developed in a pair of highly pressurized submarine pipelines along a strait crossing. By adopting linear cubic ®nite elements, the author 6 performed dynamic stress calculations using a point iterative solution algorithm to investigate the response of submarine pipelines to earthquake generated motions in the vertical plane.…”

“…optimization, 1±3 negative support reaction monitoring 4 and successive over-relaxation (SOR). 5,6 Maier and Andreuzzi 1 analysed elastic and elasto-plastic structural deformations by formulating a linearly complementary problem leading to a pair of dual quadratic programming (QP) optimization problems. Using a similar technique, Stavroulakis et al 2 expanded the optimal control theory so as to include the seabed-pipeline frictional eects during the random contact process.…”