A modification of the enhanced assumed strain concept is proposed to avoid volumetric locking phenomena in finite elements using higher‐order p‐shell element formulations based on Lagrangean polynomials and a linear finite shell kinematics. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

No abstract

SUMMARYThe deficiency of volumetric locking phenomena in finite elements using higher-order shell element formulations based on Lagrangean polynomials and a linear finite shell kinematics cannot be avoided by the existent enhanced assumed strain (EAS) concept established for low-order elements. In this paper a consistent modification of the EAS concept is proposed to extend its applicability to higher-order shell elements. This modification, affecting the transversal normal strain for polynomial orders p>1, eliminates pathological modes caused by volumetric locking. The efficiency of the proposed extended EAS method is demonstrated by means of eigenvalue analyses and two representative numerical examples.

The considerable progress in computational power has increased the attractivity of 3D‐p‐finite‐elements as a versatile tool in structural analysis. Due to its flexibility, the lack of various locking phenomena inherent to low order shell elements and the possibility of an a posteriori error assessment, 3D‐p‐finite‐elements have become an attractive alternative to the h‐method even for analyses of thin‐walled structures. In this paper a comparison of 3D‐p‐ and higher order shell elements concerning aspects of accuracy and efficiency is presented.