The Once and Future Steel Bridge

Some of the highlights of steel bridge design and construction during the 20th century are presented, and some thoughts for the near-term future of steel bridges are developed on the basis of the emergence of new materials and design processes. The “future-oriented” portions of the paper are intended to summarize research during the last decade of the 20th century dealing with the implementation of improved steels. As will be seen, the world community appears to be developing several of the same general concepts for future applications. Some of the ideas presented are speculative at this time, but it will be shown that commercialization is already under way. Finally, some thoughts on needed future developments in specification and design focus are considered.