"Rumble strip" is the official name, in the UK, for the lines across the road, sometimes in a red-tinted tarmac, to warn of speed limits, etc. I have seen the term in police reports and documents from the County Council, District council and DEFRA (the governmaent Dept that deals with roads, over here)
But I have never seen or heard any reference to the bumpy bits along the side of M-Ways and dual-carriageways, to which Dub-dub refers. So I have no idea if they have an official name - certainly they don't seem to have acquired an unofficial one, which is odd in a country in which all things to do with motors and motoring attract the weirdest of nick-names.