Abstract



A numerical method of simulation the response of a submarine pipeline during launching and pullin operations is presented in this work. These operations involve severe geometric nonlinear effects due to large displacements. Also, buckling phenomena may eventually arise. Both hydrodynamic forces and fluidstructure interaction make this problem to be modeled as a dynamic 3D approach. For practical purposes, the problem is discretized in space by the finite element method. First, a brief review of several beamcolumn element formulations as well as of different approaches for including water effects employed in pipeline models is outlined in this paper. Hermitian shape functions are used in the model, assuming cubic bending displacement variations, and a linear variation in axial displacements. So, both 2D and 3D beamcolumn element formulations are implemented in the model The single span pipeline is assumed to have caps at both ends. Given an initial static equilibrium configuration of the pipeline, the simulation procedure calculates a sequence of equilibrium configurations. For each configuration, the nonlinear solution procedure consists of an incremental iterative formulation of the equilibrium equation. The computational system takes into account the changes in both intensity and direction of buoyancy forces and hydrostatic pressures. These are often called ?follower forces? which are accounted for by the load stiffness matrix concept. An updated lagrangian formulation that assumes large displacements and small strains is used. Hence, the GreenLagrange strain tensor is used. The simulation procedure is extended to perform some parametric studies. Hence, the effects of some aspects (the pipeline caps) and parameters (material properties, slenderness, among others) on global structural response are studied. Also, a brief discussion regarding whether applying 2D or full 3D beamcolumn models is included. An illustrative example is also shown. Finally, some conclusions regarding singlespan pipelines stability analysis are drawn.  
International

Si 
Congress

IV International Conference on Computational Methods for Coupled Problems in Science and Engineering  COUPLED PROBLEMS 2011 

960 
Place

Kos, Grecia 
Reviewers

Si 
ISBN/ISSN

9788487867590 


Start Date

20/06/2011 
End Date

22/06/2011 
From page

1 
To page

1 

Proceedings of the IV International Conference on Computational Methods for Coupled Problems in Science and Engineering  COUPLED PROBLEMS 2011 