General and perturbation procedures

An analysis step during which the response can be either linear or nonlinear is called a general analysis step. An analysis step during which you activate a perturbation procedure that determines the response about a base state due to perturbation loads and boundary conditions is called a linear perturbation analysis step. General analysis steps can be included in an Abaqus/Standard or Abaqus/Explicit analysis; linear perturbation analysis steps are available only in Abaqus/Standard.

A clear distinction is made in Abaqus/Standard between general analysis and linear perturbation analysis steps. Loading conditions are defined differently for the two cases, time measures are different, and the results should be interpreted differently. These distinctions are defined in this section.

Abaqus/Standard treats a perturbation analysis as a perturbation about a preloaded, predeformed state. Abaqus/Foundation, a subset of Abaqus/Standard, is limited entirely to perturbation analysis but does not allow preloading or predeformed states.

The following topics are discussed:

Related Topics
Defining an analysis
In Other Guides
Linear and nonlinear procedures