# Advanced Solver Settings : Imperfection

Real structures are not the perfect structure envisaged by the designed but contain imperfections. The design codes try to ensure that imperfections are considered in the design process. This feature allows imperfections to be included in the analysis.

## Definition

**Geometric imperfection**

A geometric imperfection is specified by a set of equations defining how the x, y and z coordinates are modified for the analysis. The simplest imperfection is typically where the x (or y) coordinate is a function of the height of the node on building

**Scaled case imperfection**

If for example a buckling analysis has been carried out then it may be appropriate to check an imperfection in which the structure assumes a scaled value of one of the buckling model shapes. Select and scale a result case as appropriate.

**Random imperfection**

This specifies a random imperfection

**Clear imperfections**

Removes any specified imperfactions