> 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/examples/steel-bridge-examples/example-steel-tub-girder-bridge-ex1-stg/bridge-geometry-ex1-stg/insertion-point-ex1-stg.md).

# Insertion Point

This section defines the girder insertion points at each support line.

{% hint style="info" %}
**Navigation:** Bridge Geometry > Insertion Point

For detailed parameter explanations, see the [Insertion Point Reference](https://docs.openbrim.org/templates/steel-tub-girder-bridge-workflow/bridge-geometry-stg/insertion-point-stg).
{% endhint %}

## Steps

### Step 1: Navigate to Insertion Point

Navigate to **Bridge Geometry > Insertion Point** in the tree view.

![Insertion Point navigation](https://openbrim.atlassian.net/wiki/download/attachments/2169044996/image-20230216-133156.png?api=v2)

### Step 2: Create First Insertion Point

Click the **three-dot icon** on the first **Location** cell and set it to **Abut1**.

### Step 3: Define Points for Tub Girders

Since there are two tub girders, create two insertion points at each support line.

![Insertion points layout](https://openbrim.atlassian.net/wiki/download/attachments/2169044996/image-20230216-140309.png?api=v2)

### Step 4: Set Transverse Offsets

Enter **Transverse Offset** values of **-12** and **+12** to position insertion points for each girder.

### Step 5: Complete All Support Lines

Repeat for all support lines (Abut1, Pier2, Pier3, Abut4).

<details>

<summary><strong>Quick Tip:</strong> Skew Angle Calculation</summary>

For skewed supports, calculate transverse offset (T value) based on skew angle:

![Skew transverse offset](https://openbrim.atlassian.net/wiki/download/attachments/2169044996/image-20230216-140820.png?api=v2)

![Skew longitudinal offset](https://openbrim.atlassian.net/wiki/download/attachments/2169044996/image-20230216-141049.png?api=v2)

</details>

<details>

<summary><strong>Quick Tip:</strong> Transverse Offset Direction</summary>

Offset values use the PGL (Profile Grade Line) as the reference point.

</details>

![Offset reference](https://openbrim.atlassian.net/wiki/download/attachments/2104689432/image-20230216-130246.png?api=v2)

## Verification

{% hint style="success" %}
The completed insertion point layout is shown below.
{% endhint %}

![Completed insertion points](https://openbrim.atlassian.net/wiki/download/attachments/2169044996/image-20230216-142643.png?api=v2)


---

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