Bridge patentIn 1935, a U.S. patent for a bridge with open-mesh steel flooring was issued to Walter E. Irving of the Irving Subway Grating Co. (No. 1,991,154). His bridge deck design was non-skid, self-cleaning, self-draining and remained free from snow accumulation. Being relatively light in weight and offering little resistance to wind pressure made it suitable for a bridge of the bascule (drawbridge) or vertical lift type, and resulted in a saving of power needed to operate the opening of the bridge. The first bridge in the U.S. to use such open-mesh steel flooring was the University Bridge in Seattle, Washington, which was rebuilt and re-opened on 7 Apr 1933. A previous patent for a design of continuous metal grating (No. 1,629,134) was issued on 17 May 1917, and assigned to Irving Iron Works Co.« |
