While steel arched bridges are not uncommon, the client's request that Weidlinger use arches to support the existing trusses was unusual and contributed significantly to the complexity of the project. The results more than made up for the challenge of the arch solution: the appearance of the bridge was improved by adopting this scheme over the original girder scheme. The evolution of the project has application to the retrofit of other historic structures in several important ways. 1. It proves that the appearance of historic structures need not be compromised, and can even be enhanced, despite the complex geometry and outdated materials of the original. 2. It suggests that the introduction of a contrasting element can be used to combine historic and modern forms to attain a graceful appearance. 3. It demonstrates that an historic structure can be restored in an emergency situation and under stringent traffic restrictions. 4. It acts as a warning that retrofitted historic structures may have smaller safety margins than indicated by visual inspection alone due to factors in the original design and that sophisticated analysis is helpful to determine adequacy after several rehabilitations have increased dead loads.
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