girder vs tie beam

girder

noun
  • A beam of steel, wood, or reinforced concrete, used as a main horizontal support in a building or structure. 

  • One who girds; a satirist. 

tie beam

noun
  • a horizontal beam that serves to prevent two other structural members from separating while forming the base of a triangular truss for a pitched roof. 

How often have the words girder and tie beam occurred in a corpus of books? (source: Google Ngram Viewer )