Abaqus Theory Manual Version 6.7 by Simulia

Abaqus Theory Manual Version 6.7 by Simulia


The Abaqus finite element system includes:

• Abaqus/Standard, a general-purpose finite element program;
  
• Abaqus/Explicit, an explicit dynamics finite element program;
  
• Abaqus/CAE,
  an interactive environment used to create finite element models, submit
  Abaqus analyses, monitor and diagnose jobs, and evaluate results; and
  
• Abaqus/Viewer, a subset of Abaqus/CAE that contains only the postprocessing capabilities of the Visualization module.
  

Several
add-on options are available to further extend the capabilities of
Abaqus/Standard and Abaqus/Explicit. The Abaqus/Aqua, Abaqus/Design,
and Abaqus/AMS options work with Abaqus/Standard. Abaqus/Aqua contains
optional features that are specifically designed for the analysis of
beam-like structures installed underwater and subject to loading by
water currents and wave action. The Abaqus/Design option enables you to
perform design sensitivity analysis (DSA). Abaqus/AMS is an optional
eigensolver that works within Abaqus/Standard providing very fast
solution of large symmetric eigenvalue problems. The Abaqus
co-simulation technique provides two applications, available as
separate add-on capabilities, for coupling between Abaqus and
third-party analysis programs. Abaqus/Foundation is an optional subset
of Abaqus/Standard that provides more cost-efficient access to the
linear static and dynamic analysis functionality in Abaqus/Standard.
These options are available only if your license includes them.

This manual describes the theories used in Abaqus. Many sections in
this manual apply to both Abaqus/Standard and Abaqus/Explicit. Certain
sections obviously apply only to either Abaqus/Standard or
Abaqus/Explicit; for example, all sections in the chapter on procedures
apply to Abaqus/Standard, except the section discussing the explicit
dynamic integration procedure, which applies to Abaqus/Explicit. If it
is not obvious to which program a section applies, it is clearly
indicated.
The objective of this manual is to define the theories used in Abaqus
that are generally not available in the standard textbooks on
mechanics, structures, and finite elements but are well known to the
engineer who uses Abaqus. The manual is intended as a reference
document that defines what is available in the code. Nevertheless, it
is written in such a way that it can also be used as a tutorial
document by a reader who needs to obtain some background in an
unfamiliar area. The material is presented in a way that should make it
accessible to any user with an engineering background. Some of the
theories may be relatively unfamiliar to such a user; for example, few
engineering curricula provide extensive background in plasticity, shell
theory, finite deformations of solids, or the analysis of porous media.
Yet Abaqus contains capabilities for all of these models and many
others. The manual is far from comprehensive in its coverage of such
topics: in this sense it is only a reference volume. The user is
strongly encouraged to pursue topics of interest through texts and
papers. Chapter 7, “References,”
at the end of this manual lists references that should provide a
starting point for obtaining such information. (Abaqus does not supply
copies of papers that have appeared in publications other than those of
Abaqus. EPRI reports can be obtained from Research Reports Center
(RRC), Box 50490, Palo Alto, CA 94303.)
Chapter 1, “Introduction
and Basic Equations,” discusses the notation used in the manual, some
basic concepts of kinematics and mechanics—such as rotations, stress,
and equilibrium—as well as the basic equations of nonlinear finite
element analysis. Chapter 2, “Procedures,”
describes the various analysis procedures (nonlinear static stress
analysis, dynamics, eigenvalue extraction, etc.) that are available in
Abaqus. Chapter 3, “Elements,” describes the element formulations. Chapter 4, “Mechanical Constitutive Theories,” describes the mechanical constitutive theories.
Chapter 5, “Interface Modeling,” discusses the most important aspects of the contact/interaction formulation in Abaqus/Standard. Chapter 6, “Loading and Constraints,” describes the formulation of some of the more complicated load types and multi-point constraints