barricade vs road block

barricade

noun
  • A barrier constructed across a road, especially as a military defence 

  • An obstacle, barrier, or bulwark. 

  • A place of confrontation. 

verb
  • to close or block a road etc., using a barricade 

  • to keep someone in (or out), using a blockade, especially ships in a port 

road block

How often have the words barricade and road block occurred in a corpus of books? (source: Google Ngram Viewer )