North Avenue Bridge over the Fox River, Aurora, Illinois

The original six span concrete arch structure, approximately 550’ in total length, which carries North Avenue over the Fox River in Aurora, Illinois was constructed in the 1920’s. This paper describes how, in 2000, the task of investigating the structural and functional condition of the existing structure was undertaken. The outcome of the investigation indicated the superstructure and portions of the substructure were in need of replacement to carry current design loads. The existing concrete arches and underlying arch foundations would be allowed to remain with limited structural repairs. Because of the historical nature of the structure, the task undertaken by the design team was to design a new structure that would recreate the original look and character of the nearly 80-year-old bridge. The original 1920’s era plans were found and used as the starting point. The original ornamental concrete railings along with the ornamental lights were recreated on the new structure. Likewise, identical spandrel arch beam size and spacing, and column size and spacing, were used in order to obtain historical agency concurrence on the project. Precast elements were used for the railing, transverse beams, deck planks, and other members in order to reduce the amount of falsework required and speed the construction of the project.