Shell structures—a sensitive interrelation between physics and numerics

It is apparent that physics and numerics are strongly linked in every serious undertaking in computational mechanics. This is in particular pronounced when the matter of study excels through a very sophisticated, even sometimes tricky physical behaviour. Such a delicate characteristic is the trademark of shell structures, which are the most often used structural components in nature and technology. This outstanding position in the hierarchy of all structures is due to their curvature allowing to carry transverse loading in an optimal way by in-plane membrane actions, despite an often extreme slenderness. As typical for optimized systems their performance might be on the one hand excellent, but can also be extremely sensitive to certain parameter changes on the other hand. This prima donna like mechanical behaviour with all its sensitivities is of course carried over to any numerical scheme. In other words it is a fundamental precondition to understand the principle features of the load carrying mechanisms of shells before designing and applying any numerical formulation. The present study addresses this peculiar interrelation between physics and numerics. At first typical characteristics of shell structures are described; this include their benefits but also their extreme sensitivities. In the second part these aspects are reflected on related computational models and numerical procedures. This discussion is carried through a number of selected problems and examples. It need to be said that the paper is the outcome of a general plenary lecture addressing fundamental aspects rather than concentrating on a specific formulation or numerical scheme.

[1]  Ekkehard Ramm,et al.  Time integration in the context of energy control and locking free finite elements , 2000 .

[2]  David H. Allen,et al.  Modeling of Delamination Damage Evolution in Laminated Composites Subjected to Low Velocity Impact , 1994 .

[3]  F. Hashagen,et al.  Numerical analysis of failure mechanisms in fibre metal laminates : proefschrift , 1998 .

[4]  Jan Belis,et al.  Numerical stress analysis of the Fredericton Water tower collapse according to a proposed modified reference length in the ECCS rules for liquid-filled conical shells. , 2001 .

[5]  Wolfgang A. Wall Fluid-Struktur-Interaktion mit stabilisierten Finiten Elementen , 1999 .

[6]  Ekkehard Ramm,et al.  Generalized Energy–Momentum Method for non-linear adaptive shell dynamics , 1999 .

[7]  S. Pellegrino,et al.  Computation of Wrinkle Amplitudes in Thin Membranes , 2002 .

[8]  Charles R. Steele,et al.  ASYMPTOTIC ANALYSIS AND COMPUTATION FOR SHELLS by , 2022 .

[9]  E. Ramm,et al.  Shear deformable shell elements for large strains and rotations , 1997 .

[10]  J. Schlaich,et al.  Teileinsturz der Kongresshalle Berlin ‐ Schadensursachen. Zusammenfassendes Gutachten. , 1980 .

[11]  E. Ramm,et al.  On the mathematical foundation of the (1,1,2)-platemodel , 1999 .

[12]  Kurt Maute,et al.  Adaptive topology optimization of shell structures , 1996 .

[13]  Ekkehard Ramm,et al.  THE CHALLENGE OF A THREE-DIMENSIONAL SHELL FORMULATION — THE CONDITIONING PROBLEM — , 2000 .

[14]  Antonio DeSimone,et al.  Folding energetics in thin-film diaphragms , 2002, Proceedings of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences.

[15]  Rowland J. Mainstone Developments in structural form , 1975 .

[16]  E. Ramm,et al.  On the physical significance of higher order kinematic and static variables in a three-dimensional shell formulation , 2000 .

[17]  Ekkehard Ramm,et al.  Buckling and imperfection sensitivity in the optimization of shell structures , 1995 .

[18]  Matthias Hörmann,et al.  Nichtlineare Versagensanalyse von Faserverbundstrukturen , 2002 .

[19]  Jintai Chung,et al.  A Time Integration Algorithm for Structural Dynamics With Improved Numerical Dissipation: The Generalized-α Method , 1993 .

[20]  R. Van Impe,et al.  Elastic and Elastic-Plastic Buckling of Liquid-Filled Conical Shells , 1988 .

[21]  Martin P. Bendsøe,et al.  Optimization of Structural Topology, Shape, And Material , 1995 .

[22]  Ekkehard Ramm,et al.  A General Finite Element Approach to the form Finding of Tensile Structures by the Updated Reference Strategy , 1999 .

[23]  Ekkehard Ramm,et al.  Nonlinear failure analysis of laminated composite shells , 2003 .

[24]  T. Hughes,et al.  Iterative finite element solutions in nonlinear solid mechanics , 1998 .

[25]  F. Armero,et al.  On the formulation of high-frequency dissipative time-stepping algorithms for nonlinear dynamics. Part I: low-order methods for two model problems and nonlinear elastodynamics , 2001 .

[26]  Ing. Ekkehard Ramm,et al.  Shape optimization of shell structures , 1993 .

[27]  E. Ramm,et al.  Structural optimization and form finding of light weight structures , 2001 .

[28]  Maria Esslinger,et al.  Postbuckling Behavior of Structures , 1975 .

[29]  Eberhard Schunck,et al.  Heinz Isler Schalen , 1986 .

[30]  Wolfgang A. Wall,et al.  Parallel multilevel solution of nonlinear shell structures , 2005 .

[31]  E. Ramm,et al.  A unified approach for shear-locking-free triangular and rectangular shell finite elements , 2000 .

[32]  N. K. Srivastava Finite element analysis of shells of revolution , 1986 .

[33]  Daniel Pinyen Mok Partitionierte Lösungsansätze in der Strukturdynamik und der Fluid-Struktur-Interaktion , 2001 .

[34]  E. Ramm,et al.  Large elasto-plastic finite element analysis of solids and shells with the enhanced assumed strain concept , 1996 .