弓弦式桁梁

bow girder bow string slab and girder floor beam and girder construction girder and beam connection have a second string to one's bow bow and scrape girder string bow spandrel girder inverted bow and chain girder bow girder Bow string bow string pattern have a second string to one's bow bow and scrape slab and girder slab and girder floor beam and girder construction beam and girder framing girder and rail mill girder and beam connection