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<br />Project Description <br /> <br />An existing seven span riveted plat girder bridge carried the former Coal Line Railroad over the St. Joseph <br />River. The existing structure was constructed in 1926 and is 327 feet in length. According to information <br />obtained from the City of South Bend Engineering Department, the Coal Line Railroad Bridge was taken out of <br />service after the railroad had concerns the foundations may have settled. An apparent dip in the track is <br />evident in Spans 5 and 6 along the south side of the bridge. An inspection of the bridge was conducted by <br />United Consulting on May 9, 2016. After evaluating the field survey data and completing the visual inspection <br />of the bearing assemblies, it was determined the apparent dip in the deck could be attributed to excessive <br />pack rust that has developed at locations where multiple shim plates were used in the bearings. The shim <br />plates on the north side of the bridge were found to have more pack rust in comparison to the bearings on the <br />south side of the bridge. This is likely due to the south side of the bridge receiving more direct sunlight which <br />has kept the bearings drier and slowed the corrosion. The difference in the top of beam elevations from the <br />north to the south side of the bridge correlate closely with the difference in pack rust from each side of the <br />bridge. It is recommended the steel bearings be eliminated throughout the structure and elastomeric bearing <br />pads be used on reconstructed concrete beam seats. <br /> <br />The following is a summary of the major items that are anticipated for this bridge rehabilitation project: <br /> <br />Bridge Deck and Superstructure: <br /> <br /> The existing rails and timber railroad ties will be removed. <br /> Existing steel girders will be cleaned and painted. <br /> New concrete deck with 14 foot clear roadway width will be placed on the existing beams. <br /> Pedestrian hand rail will be installed on new deck. <br /> Overlooks will be constructed on both sides at Piers 3 and 6. <br /> <br />Substructure and Foundation: <br /> <br /> New concrete beam seats with elastomeric bearing pads are recommended to replace the existing <br />steel bearing assemblies. This work can be completed by temporarily supporting the steel <br />superstructure. <br /> The bent and pier caps will be raised to accommodate the proposed elastomeric bearing pads. <br /> The scaling and spalling in the piers will be cleaned and patched. <br /> The cracks with efflorescence in the piers and pier caps will be epoxy injected. <br /> The timber fenders around the piers will be removed to eliminate trapped debris. <br /> Any debris currently trapped on the substructure will be removed. <br /> <br />Scour and Scour Countermeasures: <br /> <br />Scour countermeasures consisting of Class I riprap will be placed at each of the piers to protect the <br />foundations. Approximately 75 linear feet of this riprap will be below the ordinary high water mark (OHWM) of <br />the St. Joseph River.