# Concrete Box Girder \[CBG]

## Location

**Support Lines:** Users should use the 'Pick...' option to select all of the support lines that the box girder will pass through.

**Transverse Offset (from PGL):** The transverse offset value is the distance from the center of the box girder to the PGL. When looking upstation along the PGL, positive values indicate a shift to the right, and negative values indicate a shift to the left.

**Material:** The material of the box girder can either be assigned from predefined materials in the Properties section or imported.

**Box Girder Shapes:** To define cross-sections and variations along the girder, use the 'Edit...' option.

* **Reference Support Line:** Select the initial support line where the box girder shape begins.
* **Longitudinal Offset:** Specify the longitudinal offset value from the support line along the PGL.
* **Box Girder Shape:** Assign the box girder shape defined previously in the 'Box Girder Shape' section.
* **Variation \[None/Linear/Parabola]:** The changes in the cross sections of the box girder can be defined as 'None,' 'Linear,' or 'Parabola.

## FEA

**Mesh Size :**

**Rigid Section (for substructure connection):**

## Detailing

**Clear Cover:**

**Stirrup Diameter:** Nominal diameter of the stirrups (shear reinforcement).

## Geometry (Additional)

**Start Cantilever Length:** Cantilever length of the box girder at the start station. Affects only the 3D model.

**End Cantilever Length:** Cantilever length of the box girder at the end station. Affects only the 3D model.

**Start Top Flange Overhang:** Overhang of the top flange beyond the outer webs at the start station.

**End Top Flange Overhang:** Overhang of the top flange beyond the outer webs at the end station.

**Curve Refinement:** Discretization factor for the 3D geometry along curved alignments. Higher values produce smoother curves without affecting the FEM.

## Referencing Objects

**Construction States:** Construction States referencing this box girder (Read-only).

**Bents:** Integral bents connected to this girder (Read-only).

**End Diaphragms:** End diaphragm objects on this girder (Read-only).

**Intermediate Diaphragms:** Intermediate diaphragm objects on this girder (Read-only).

**Barriers:** Barrier objects placed on this girder (Read-only).


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