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--- wikifemfuchde2019:lesson_in_an_undefined_future [2019/04/01 09:19] – creata ebertocchi
+++ wikifemfuchde2019:lesson_in_an_undefined_future [2019/04/01 09:20] (versione attuale) – ebertocchi
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+----
+Full profile properties characterization of a generic section, based on the FE model of a segment.
+**Base model**: 2 rows of elements, 10 mm thick in the z direction profile segment.
+{{ :wikifemfuchde2019:asymm_sez_base_v000.mfd |}}
+Profile wall overall midcurve length: 391.65525 mm.
+Profile wall thickness: 4 mm.
+Material properties are set, along with the local element orientations.
+Symmetry (''symm_pxy_nz'') and skew-symmetry (''skewsymm_pxy_nz'') constraints are set for the nodes at z=0, and two RBE2 are set for the nodes at z=t=10mm,
+  * one with free warping displacements, and constrained in plane motions, named ''rbe2_skewsymm'';
+  * the other, complementary to the first and named ''rbe2_symm'', exhibits constrained o.o.p. displacements, and free in plane motion.
+Material is set as isotropic, linearly elastic aluminum (E=70000,$\nu$=0.3, $G=E/(1+\nu)$); however, the following procedure is valid for a generic monoclinic material, for which the xy plane, normal to the z profile axis direction, is a symmetry plane.
+**Axial stiffness and centroid position**
+''symm_pxy_nz'' b.c. and the ''rbe2_symm'' RBE2 are activated.
+A positioning constraint is added with respect to the xy in plane translations, and the o.o.p. rotation.
+A z displacement equal to $t/E$ is imposed at the RBE2 control node, while its other degrees of freedom are constrained to zero.
+A uniform unit stress condition should be obtained if the material is homogeneous.
+A z reaction force component is obtained, that for an homogeneous material equates the cross sectional area. Such force is here called $F$.
+Being the control node not positioned at the centroid, x and y components of the reaction moment at such control node are expected to be nonzero, and equal to