# Temperature Load

This section defines uniform temperature loads for thermal expansion and contraction.

{% hint style="info" %}
**Navigation:** Loading > Loads > Temperature Load
{% endhint %}

## Overview

Temperature variations that occur throughout the day exert two types of loads on bridges: expansion and contraction.

## Steps

### Step 1: Navigate to Uniform Temperature Load

Navigate to **Loads > Temperature Load > Uniform Temperature Load** in the tree view.

![Temperature Load navigation](https://openbrim.atlassian.net/wiki/download/attachments/2170028033/image-20230224-115515.png?api=v2)

### Step 2: Select Construction Stages

Click the **three-dot icon** on the **Stage** cell and select **TUExpStage** and **TUContrStage** to define the temperature loads that have an impact on the bridge.

![Stage selection](https://openbrim.atlassian.net/wiki/download/attachments/2170028033/image-20230224-115533.png?api=v2)

![Stage assignment](https://openbrim.atlassian.net/wiki/download/attachments/2170028033/image-20230224-115707.png?api=v2)

### Step 3: Assign Bridge

Click the **three-dot icon** on the **Bridge** cell and set Bridge as **BRG1**.

![Bridge assignment](https://openbrim.atlassian.net/wiki/download/attachments/2170028033/image-20230224-120236.png?api=v2)

### Step 4: Set Temperature Changes

Set Temperature Change from mean \[F] parameters:

* UTL1: **40 F** (expansion)
* UTL2: **-40 F** (contraction)

The purpose is to calculate the loads that may occur under these critical temperatures.

![Temperature values](https://openbrim.atlassian.net/wiki/download/attachments/2170028033/image-20230224-120745.png?api=v2)

## Verification

{% hint style="success" %}
Temperature loads for expansion and contraction should be properly defined.
{% endhint %}