This document provides details of ten benchmark tests for 3-D Beam and Shell Finite Element (FE) assemblies exhibiting getometric non-linear behaviour. Each benchmark test is presented in full, a summary description being given in Ref. 1. The work was commissioned by NAFEMS and undertaken by NNC Ltd under the direction of the Non-linear Working Group (now the Computational Structural Mechanics Working Group).

The object of the report is to provide full details of a set of benchmarks problems illustrating the major attributes of geometric non-linear behaviour which a finite element code may be required to deal with when solving ‘real life’ industrial problems. The structures are idealised using 3D beam and shell formulations. Such structures are said to exhibit geometric non-linearity if their response to the loading of the actual deformation or strain. The benchmarks presented here are however restricted to finite displacement, finite rotation and small strain behaviour. Large strain problems are specifically excluded.

The ten benchmarks will:

• allow verification and searching checks of the ability of finite element computer codes to produce acceptable solutions to problems involving geometric non-linearity in structures idealised by assemblies of 3-D shell or beam elements.

• exercise a user’s ability to model physical behaviour and interpret results from non-linear finite element analysis.

• Allow education/training of inexperienced persons with respect to the use of finite element packages in solving non-linear problems.

A summary of the attributes of geometric non-linear behaviour covered by this set of problems is given. The concept of ‘target’, ‘reference’ and ‘published’ solutions is then introduced. Finally, a full description of each benchmark problem and solutions is presented.

Contents

Summary

Introduction

The benchmarks

Attributes

Summary description

Solution definition

Finite element formulations

Detail descriptions of the benchmark tests

References

ACKNOWLEDGEMENTS