> For the complete documentation index, see [llms.txt](https://docs.openbrim.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.openbrim.org/templates/openbrimfea/loads-fea/staged-construction-fea/changes-fea.md).

# Changes \[FEA]

Changes allow you to modify element properties at specific construction stages. This is useful for modeling scenarios where structural properties change during construction, such as boundary condition changes (releasing temporary supports), stiffness modifications (cracked vs. uncracked sections), or material property updates.

## FENode

Override node properties at a specific construction stage.

**Analysis Case:** The construction stage at which this property change takes effect.

**FENode:** The name of the node whose property will be modified.

**Property:** The node property to change (e.g., Tx, Ty, Tz, Rx, Ry, Rz for boundary condition modifications such as releasing a temporary restraint).

**Value:** The new value to assign to the selected property at this construction stage.

## FESpring

Override spring element properties at a specific construction stage.

**Analysis Case:** The construction stage at which this property change takes effect.

**FESpring:** The name of the spring element whose property will be modified.

**Property:** The spring property to change (e.g., Tx, Ty, Tz, Rx, Ry, Rz for stiffness modifications).

**Value:** The new value to assign to the selected property at this construction stage.

## FELine

Override line element properties at a specific construction stage.

**Analysis Case:** The construction stage at which this property change takes effect.

**FELine:** The name of the line element whose property will be modified.

**Property:** The line element property to change (e.g., section area, inertia, modulus, or end releases).

**Value:** The new value to assign to the selected property at this construction stage.

## FESurface

Override surface element properties at a specific construction stage.

**Analysis Case:** The construction stage at which this property change takes effect.

**FESurface:** The name of the surface element whose property will be modified.

**Property:** The surface element property to change (e.g., thickness, modulus, Poisson's ratio).

**Value:** The new value to assign to the selected property at this construction stage.

## FEVolume

Override volume element properties at a specific construction stage.

**Analysis Case:** The construction stage at which this property change takes effect.

**FEVolume:** The name of the volume element whose property will be modified.

**Property:** The volume element property to change (e.g., modulus, Poisson's ratio).

**Value:** The new value to assign to the selected property at this construction stage.


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