Thermal variations should be taken into account due to seasonal changes, during which a uniform heating of the structure can occur, and in another season, cooling of the structure.

Hence, if thermal loads are to be introduced, carry out the following steps:

1. Create two additional live load loadcases in Job > Loads > Additional loadcases > live load. Call them +30 and –30 for example.
2. Select Load > Introduce loads on bars and activate all the bars of the structure. To do so, click in the topmost corner and open a capture window.
3. In the dialogue box that opens, select +30 for the loadcase and click on the Dt icon. Type a value of 30 in the value box.
4. Select Load > Introduce loads on bars and activate all the bars of the structure. To do so, click in the topmost corner and open a capture window.
5. In the dialogue box that opens, select -30 for the loadcase and click on the Dt icon. Type a value of -30 in the value box.