Answer:
If you want to generate an arc in RSTAB 9, you can use the parameterized circular arc in the block manager. To do this, simply open the block manager as shown in Image 01 and select the corresponding block.
In the following dialog box, you can see a preview image of the inserted block. Using the block nodes shown, you can select an insertion point and set it to a node in the model or to manually defined coordinates; see Image 02.
The parameters and member properties can be edited in the Structure tab. This is shown in Image 03.
Image 04 then shows the created round arch.
