.. _v6.01.129: **v6.01.129** SSNA129 - Elastoplastic tubes subject to axisymmetric internal/external pressures ===================================================================================================== **Summary:** This test case makes it possible to compare finite elements of plates and shells (kinematics, methods of integration into the thickness) and pipes to model homogeneous elastoplastic cylindrical tubes subjected statically to representative axisymmetric pressure loading paths, producing a solution independent of the axial direction of the tube. Three tube geometries are treated: * :math:`\mathit{h}/\mathit{R} = \mathrm{0.05}= \mathrm{1/20}`, * :math:`\mathit{h}/\mathit{R} = \mathrm{0.10}= \mathrm{1/10}`, * :math:`\mathit{h}/\mathit{R} = \mathrm{0.20}= \mathrm{1/5}` The axisymmetric pressure loading paths are: * alternating asynchronous internal/external pressures until complete discharge of the elastoplastic tube with isotropic work hardening, * monotonic internal pressure increasing up to the ruin limit, with controlled radial displacement of the elastoplastic tube without work hardening. The reference solutions are obtained by modeling using axisymmetric massive finite elements on a mesh that is very refined in terms of thickness: see modeling A. These solutions are also compared with partial analytical results. The finite elements of plates and shells tested are: * modeling B: the "DKT" [:external:ref:`r3.07.03 `] plates, * C modeling: the volume shells "COQUE_3D" [:external:ref:`r3.07.04 `]. * D modeling: the solid shells "COQUE_SOLIDE" [:external:ref:`r3.07.10 `], * E modeling: the "TUYAU_3M" [:external:ref:`r3.08.06 `] pipes, with their ability to treat swelling (radial). We compare respectively: * the radial displacement over time, * axial displacement over time, * the circumferential and radial stresses in the thickness at certain times, * the cumulative plastic deformations in the thickness at certain times. .. toctree:: :hidden: self .. toctree:: :maxdepth: 2 :numbered: Probleme_de_reference Solution_de_reference Modelisation_A Modelisation_B Modelisation_C Modelisation_D Modelisation_E Synthese_des_resultats Description_des_versions_du_document Bibliographie