K Bap Express, a Korean fast-food chain, is replacing the short-lived Pines of Rome Express in Rockville. K Bap specializes in dumplings, bulgogi, bibimbap, fried chicken and rice cakes. Pines of Rome, a satellite of the Bethesda Italian restaurant, closed in July after less than two years at the Congressional North shopping center. Before that, the space was home to Congressional Deli.