Broken Steel raises the level cap to 30, not the Pitt or OA. Did you get a pop up that said your level cap had increased to 30? Mine says "Broken Steel is loaded. Level cap increased to 30."
Are you on PC? If you are, use the FO3 Launcher, it has to be the Launcher and select Data Files from the loading page and then put a checkmark next to the DLC names you want to load.
Broken Steel raises the level cap to 30, not the Pitt or OA. Did you get a pop up that said your level cap had increased to 30? Mine says "Broken Steel is loaded. Level cap increased to 30."