Patent ID: 7921562

Claim:
A method of welding a deck plate and a closed section rib both constituting a steel plat, wherein the deck plate is comprised of a steel plate having a first thickness; the closed section rib is comprised of a steel plate having a second thickness, the rib comprising the steel plate thereof bent to define a rib, to define an edge of the steel plate forming the rib, and to define a root portion formed at the edge of the steel plate forming the rib; the method comprising: working the root portion of the closed section rib to have a flat surface in parallel with a surface of the deck plate, wherein a dimension of the flat surface along a surface direction of the steel plate deck is 5% to 50% of a thickness of the steel plate deck forming the closed section rib; and welding the deck plate and the closed section rib while making the flat surface of the closed section rib be in contact with the surface of the steel deck plate.