Electric welds for building construction

A pressure machine capable of applying a load of 10,000,000 lb. was used at the Bureau of Standards in Washington to determine whether steel girders welded by electricity can stand stresses necessary in skyscraper construction. The welds made good. In order to make the test some steel plates were fabricated by electric welding into a plate girder 15 ft. long having a web plate 1/2 in. thick and 24 in. deep. The flanges were 12 in. wide, one was 1 3/4 in. thick and the other 1 7/8 in. thick. A 9 1/2-in. cover plate was used on the top and bottom flanges. Pressure was applied in the middle of a 13 1/2-ft. span. The web buckled and the girder had deflected several inches before the electric welds connecting the web to the top flange failed at the ends. The welds withstood a load of well over 410 tons which was considered to be the full strength of the web.