The bridge carrying Bartell Road over I-81 is a symmetrical four span structure located in the town of Brewerton, NY. Both end spans were originally constructed with open metal grating near the curb lines to facilitate drainage. The open metal grating permitted chloride laden water to come in contact with, and severely corrode, the first interior girders on both sides of both end spans. At some point in the past, an attempt was made to stop the water from reaching the girders by filling the open metal grating with concrete, but this had little effect. A top view of the concrete filled metal grating and the corrosion of the first interior girder elevation view of the existing structure and a may be found in Figure 1. This structure is a major connector from I-81 to the local businesses and seasonal tourism surrounding Oneida Lake. To restrict the loading on the structure would have a major impact on the local economy during the busy summer season. Due to its deteriorated condition, the bridge was programmed for replacement, with construction to begin within a year. In early 2009, bridge inspectors conducted the regularly scheduled hands-on inspection of the structure. During this inspection, it was noted that the rate of corrosion had increased rapidly from the previous inspection. In some areas, the bottom flange of the first interior girders had up to 30% section loss. Using conservative assumptions for the material properties of the structure, code based analysis indicated that the structure's load carrying capacity had deteriorated to the point that a load limit restriction may be warranted. With a bridge replacement project beginning within the next twelve months, it was decided to conduct a load test of the structure to determine its actual load carrying capacity with the hope that the bridge response to a known applied load would deem the structure safe, and permit unrestricted traffic until the new structure could be constructed.
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