Abstract
In linear isogeometric analysis of beams, the success of selective reduced integration and projection methods in mitigating the locking phenomenon has been proved. This study further extends these methods to the geometrically nonlinear analysis with two isogeometric Timoshenko–Ehrenfest beam formulations, that is,
-continuous NURBS selective reduced integration and
formulations. Three numerical examples are presented examining overall structural responses, strain energy, recovery of cross-sectional stress resultants, and convergence properties. Although the two proposed formulations exhibit the locking-free behavior for highly flexible beam structures, the
formulation offers higher accuracy, and the proper recovery of strain measures and cross-sectional stress resultants.
Acknowledgment
The first author acknowledges the Postdoctoral Fellowship awarded by the Second Century Fund (C2F) from Chulalongkorn University, Thailand.