# Girder Load \[TB]

## Girder Load

Girder loads are applied as line loads along the top or bottom flange of a selected girder. The magnitude is entered in terms of per-unit-length forces and moments, and the load is activated at a user-selected construction stage.

**Girder:** Select the girder to which the load will be applied. The user must provide a girder selection; the bridge alignment and flange reference points are pulled from the selected girder.

**Stage:** Choose the construction stage at which to apply the line load. When left empty, the load is defined but not activated on any construction stage.

**Applied Flange \[Top/Bottom]:** Specify whether the line load is applied along the top flange (1, default) or the bottom flange (2) of the selected girder.

**Fx:** Force per unit length in the longitudinal direction along the girder alignment.

**Fy:** Force per unit length in the direction perpendicular to the girder alignment.

**Fz (Gravity):** Force per unit length in the vertical direction. A positive value indicates a load in the global -Z (gravity) direction. For typical self-weight-like loads (wearing surface, stay-in-place formwork, utility lines), enter positive values.

**Mx:** Moment per unit length about the longitudinal axis along the girder alignment.

**My:** Moment per unit length about the axis perpendicular to the girder alignment.

**Mz:** Moment per unit length about the vertical axis.

{% hint style="info" %}
Although **Fz** is applied in the direction of gravity (positive values for **Fz** correspond to the downward direction), **Mz** is positive relative to the **+Z** axis (upward direction by the right-hand rule).
{% endhint %}


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