The N.C. Department of Transportation will begin a 14-month project Monday to preserve 15 area bridges over Interstate 77. The project is targeting bridges in good shape that would be far more expensive to repair or replace in future years if preventative measure are not taken now, said Garland Haywood, the departments division bridge engineer for the Charlotte area.
Its really to prolong the life of the bridges, he said. These are bridges that were built anywhere from 1968 to 1973 ... theyre in good shape now, but (after the preservation project) were going to get at least 20 more years out of these bridges without any maintenance.
The maintenance project will cost $5 million for all the bridges and is expected to be completed by the end of August 2013. According to Haywood, the cost of replacing any of these bridges, if they were allowed to deteriorate to an irreparable state, would be several times the cost of preservation.
Any one of these bridges could cost us $800,000 to maybe $1.5 million to replace, Haywood said. This is basically upkeep ... we want to do this to save money.
The contractor chosen by the state DOT, HRI Bridge Co. of State College, Pa., will work on the bridges one at a time over the course of the projects. HRI Bridge will start with the John Belk Freeway bridges over I-77, spending roughly two to four weeks on each bridge as they work north. The last bridge to be preserved will be the Stumptown Road crossing in Huntersville.
Nearly all the construction will be performed at night, Haywood said, with crews working on one lane at a time to prevent closures. The only roads that will close temporarily and require detours will be the entrance and exit ramps at John Belk Freeway and N.C. 49/South Tryon Street.
While each bridge requires a slightly different approach, the most common preservation technique is a deck overlay. This requires crews to remove the existing deck and apply a latex modified concrete overlay. Some bridges will also have bearing plates replaced or cracks sealed in their concrete support columns.
Theyve each got different work depending on the bridge, Haywood said. Basically, we want to preserve what we have. Theyre in good shape now and we need to try and hold on to that infrastructure.