New Search
i fN61NffRS~ _ $ ; <br /> <br /> r ~ Transportation • Structural • Civil • Surveying • Inspection • Environmental <br /> March 2, 2004 <br /> Steve Gallup P.E. <br /> City of Eugene Public Works <br /> 244 East Broadway <br /> Eugene, OR 97401 <br /> Re: Ferry St. Bridge Repair <br /> OBEC Job No. 89-71 <br /> Dear Steve: <br /> Thank you for requesting our services for the repair of the Ferry St. Bridge. At your request, OBEC is to <br /> develop engineering plans and specifications for the repair of shear cracks in the approach spans of <br /> Bridge No. 06648. The following is our approach for development of the design details and <br /> implementation of construction repairs to the shear cracks. <br /> Background <br /> Bridge No. 06648, built in 194.8, is 795 feet long and consists of two steel truss spans totaling 442 feet, <br /> and seven reinforced concrete deck girder (RCDG) spans, totaling 353 feet in length. A major <br /> construction widening project was completed in 2000 in which new RCDG girder lines were added to <br /> each side of the bridge approach spans. In September 2003, significant cracks up to 0.040" were noted in <br /> two original RCDG girders of Spans 1 & 2. At that time OBEC was asked to verify the cracks, perform a <br /> ground level inspection of other girders, and re-load rate the bridge with the current ODOT guidelines for <br /> shear cracks. Additional cracks over 0.015" were noted in several girders with approximately 75 lineal <br /> meters of cracks requiring injection. The load rating revealed a significant drop in load capacity when <br /> utilizing the worst case condition of the 0.040" crack. ODOT has stated that the local agencies have 180 <br /> days to implement load restrictions or install repairs. <br /> OBEC recommends the following three-phase program for addressing the shear crack problems and <br /> maintaining the current load capacity of the bridge. Attached is a budget spreadsheet indicating <br /> anticipated work tasks and efforts. <br /> Phase 1-Immediate Repairs <br /> To meet the ODOT guidelines, we recommend an aggressive crack injection program that will address the <br /> immediate load restriction issues. ODOT has stated that quality epoxy injection of shear cracks will <br /> restore up to 90 percent of the concrete shear value. Combining this repair with frequent re-inspections <br /> will ensure that the original load capacity of the bridge is maintained. <br /> EUGENE <br /> (541) 599.6090 <br /> FAX (541)683-6576 <br /> 910 Country Club Road, Sui[e 1008 <br /> Eugene, Oregon 97401-1208 <br /> MEDFDBD <br /> (5411774-5590 <br /> FAX (541) 774-5591 <br /> 1335 PoplarOrive <br /> h1edford, Oregon 97504-5107 <br /> www.obec.com <br /> <br />