The influence of imperfections resulting from members can be represented by equivalent deformations in the form of initial inclinations and precambers, using the member imperfections. They are taken into account in the calculation by equivalent loads.
Usage in Program
RFEM and RSTAB provide three options for defining a member imperfection.
- Initial Sway: Equivalent to the initial inclination
- Initial Bow: Magnitude of the initial deflection of a member
- Initial Bow and Criterion: Definition of a precamber, depending on an inclination
Furthermore, the definition type can be used to specify whether the imperfection is to be user-defined or applied according to the standard specifications.
In most cases, the imperfection acts over the entire length of a member or a list of members. However, there are also the options to assign the imperfection in such a way that it acts separately on each individual member. The approaches are compared in the following image.
