There are scenarios when a Progress database will automatically emergency shut itself down. Uusually this will happen when the database consistency can't be guaranteed anymore because something is preventing the database from ensuring it. There are usual suspects like blowing the before image, insufficient space in the file system and last, but not least, hardware failure.
Remember: This is to guarantee the database consistency, therefore, if you experience automated shutdowns you need to fix the root cause in order to let the database do its work!
Other than that I am not aware of any screnarios where a Progress database would shut itself down automatically.